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Sample records for allison ms fache

  1. Overview of Allison/AGTSR interactions

    Energy Technology Data Exchange (ETDEWEB)

    Ali, S.A. [Allison Engine Co., Indianapolis, IN (United States)

    1995-10-01

    Morgantown Energy Technology Center`s Tom Bechtel`s perseverance resulted in the creation of the Advanced Gas Turbine Systems Research (AGTSR) initiative in 1992. His foresight resulted in establishing an advanced gas turbine research center. The center is supported by the Government and industry. The industry serves in an oversight role, and helps select the type of research projects to be conducted by universities. AGTSR now represents an effective university and industry partnership, and is recognized as a positive mechanism. Allison Engine Company (Allison) continues to be an active participant and a strong supporter of the Advanced Gas Turbine Systems Research initiative at Clemson University. Allison took part in early formulation stages of this university/industry consortium. We have been a member of the consortium since its inception in 1992. Allison`s senior management is cognizant of the benefits of these jointly sponsored research programs. Over the years, Allison has promoted cooperative gas turbine research and advanced technology development at many universities. This activity is conducted through direct assignments at Allison for university students, and support of research projects at various universities, focused on different disciplines of gas turbine research.

  2. Ghost signals in Allison emittance scanners

    Energy Technology Data Exchange (ETDEWEB)

    Stockli, Martin P.; /SNS Project, Oak Ridge /Tennessee U.; Leitner, M.; /LBL, Berkeley; Moehs, D.P.; /Fermilab; Keller, R.; /LBL, Berkeley; Welton, R.F.; /SNS Project, Oak

    2004-12-01

    For over 20 years, Allison scanners have been used to measure emittances of low-energy ion beams. We show that scanning large trajectory angles produces ghost signals caused by the sampled beamlet impacting on an electric deflection plate. The ghost signal strength is proportional to the amount of beam entering the scanner. Depending on the ions, and their velocity, the ghost signals can have the opposite or the same polarity as the main beam signals. The ghost signals cause significant errors in the emittance estimates because they appear at large trajectory angles. These ghost signals often go undetected because they partly overlap with the real signals, are mostly below the 1% level, and often hide in the noise. A simple deflection plate modification is shown to reduce the ghost signal strength by over 99%.

  3. Aktuelle Tendenzen im computerunterstützten (Fach- Fremdsprachenunterricht

    Directory of Open Access Journals (Sweden)

    Pawel Szerszeń

    2015-03-01

    Full Text Available Die heutigen Entwicklungen im Bereich der Kommunikations-und Informationstechnologien tragen u.a. dazu bei,dass wir immer wieder mit neuen E-Learning-Angeboten im (Fach-Fremdsprachenunterricht konfrontiert werden. Diese Tatsa-che stellt u.a. die FremdsprachendidaktikerInnen vor neue Herausforderungen, für die eine kritische Reflexion über die didakti-sche Effizienz von E-Learning-Produkten Vorrang hat. Für eine solche didaktische Reflexion muss jedoch zunächst geklärt wer-den, welche Haupttypen von E-Learning-Produkten bestehen. Das Hauptziel des vorliegenden Beitrags ist somit der Versuch, diezurzeit bestehenden Haupttypen zu erfassen, zu kategorisieren sowie mit einigen Beispielen zu veranschaulichen wie auch aufinteressante Features ausgewählter Lernplattformen/Lernprogramme und auf einige neue E-Learning-Tendenzen hinzuweisen.Dieser Überblick stellt eine nötige und geeignete Grundlage für eine zukünftig mögliche Effizienzreflexion und-diskussion vordem Hintergrund möglicher Produktvergleiche dar

  4. In defense of psychosomatic theory: A critical analysis of Allison and Heshkas critical analysis

    NARCIS (Netherlands)

    Strien, T. van

    1995-01-01

    This article analyses Allison and Heshka's (International Journal of Eating Disorders, 13, 289–295, 1993.) critical analysis of studies supporting psychosomatic theory. Questionned first is, Allison and Heshka's contention that the obese overreport emotional eating as a result of effects of demand c

  5. In defense of psychosomatic theory: a critical analysis of Allison and Heshka's critical analysis.

    Science.gov (United States)

    Van Strien, T

    1995-04-01

    This article analyses Allison and Heshka's (Internal Journal of Eating Disorders, 13, 289-295, 1993.) critical analysis of studies supporting psychosomatic theory. Questionned first is, Allison and Heshka's contention that the obese overreport emotional eating as a result of effects of demand characteristics, social desirability, and interpersonal expectancies. These effects, however, indicate that a more plausible response would be an underreport of emotional eating. Also addressed is Allison and Heshka's (Eating Disorders: The Journal of Treatment and Prevention, 1, 31-38, 1993.) contention that a high correlation between a measurement instrument and a measure of social desirability invalidates that measurement instrument. Finally, in a rebuttal of Allison and Heshka's critical analysis of studies supporting psychosomatic theory, it is elaborated why emotional eating explains so little variance in weight gain and obesity.

  6. In defense of psychosomatic theory: A critical analysis of Allison and Heshkas critical analysis

    OpenAIRE

    van Strien, T.

    1995-01-01

    This article analyses Allison and Heshka's (International Journal of Eating Disorders, 13, 289–295, 1993.) critical analysis of studies supporting psychosomatic theory. Questionned first is, Allison and Heshka's contention that the obese overreport emotional eating as a result of effects of demand characteristics, social desirability, and interpersonal expectancies. These effects, however, indicate that a more plausible response would be an underreport of emotional eating. Also addressed is A...

  7. BioFach China成为亚洲有机行业发展风向

    Institute of Scientific and Technical Information of China (English)

    左琼莹

    2010-01-01

    由中国绿色食品发展中心与纽伦堡展览集团共同主办的中国国际有机食品博览会(BioFach China)是亚洲最具影响力的有机产品贸易盛会,自2007年以来已成功举办四届。

  8. Bi0Fach China2013引领有机生活新风尚

    Institute of Scientific and Technical Information of China (English)

    尹薇

    2013-01-01

    作为中国唯一专注于有机产品的专业博览会,BioFach chian(中国国际有机食品博览会)的品牌自2007年首次从德国移植到中国,已经发展成为国内最具影响力、最权威的有机产品贸易盛会。BioFach China由纽伦堡国际博览集团携手农业部中国绿色食品发展中心共同主办,获国际有机农业运动联盟(IFOAM)的全力支持,所有参展有机产品均具有有效的有机认证证书。2013年5月23至25日,第七届BioFach China将再次于上海国际展览中心拉开帷幕。

  9. Interkulturelle kommunikative Kompetenz – ein Versuch der Operationalisierung aus dem Fach Deutsch an der dänischen Lehrerausbildung

    DEFF Research Database (Denmark)

    Bjerre, Kirsten; Daryai-Hansen, Petra

    2017-01-01

    Mit diesem Artikel versuchen wir, den Begriff 'interkulturelle kommunikative Kompetenz‘ theoretisch zu entwickeln. Wir gehen zunächst der Frage nach, warum im Fach Deutsch als Fremdsprache mit interkultureller kommunikativer Kompetenz gearbeitet werden sollte und welche Herausforderungen sich...... hierbei stellen. Im Anschluss präsentieren wir unser Modell der interkulturellen kommunikativen Kompetenz, das wir für das Fach Deutsch ain der dänischen Lehrerausbildung auf der Grundlage eines Modells von Michael Byram aus dem Jahre 1997 entwickelt haben. Byrams Modell der interkulturellen...... zunächst die Begriffe ‚Kompetenz‘, ‚Kultur‘, ‚kommunikative Kompetenz‘ und ‚interkulturelle Kompetenz‘. Wir konkretisieren die Dimensionen des Modells im Anschluss anhand eines Unterrichtsbeispiels für das Fach Deutsch an der dänischen Einheitsschule („Folkeskole“). Abschließend skizzieren wir, wie unser...

  10. BioFach China2012:绚丽多彩的有机世界

    Institute of Scientific and Technical Information of China (English)

    宋庆

    2012-01-01

    第。六届BioFachChina中国国际有机食品博览会将于2012年5月24-26日在上海国际展览中心隆重召开,这将是继BioFach纽伦堡展之后全球有机产业的又一场盛宴。届时,您所收获的将不仅是高质量的有机产品.更是健康、美好的幸福生活。

  11. No.5BioFach China 2011:五周年再创辉煌

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    2011年5月26至28日,BioFach China——中国唯一的纯有机贸易展会迎来了她的五岁生日。来自33个国家及地区的14.613名有机产品贸易商见证了这迄今为止最成功的一届展会。与去年相比,这一数字增长达到了惊人的27%(2010年:11,526)。

  12. BioFach China 五月登陆上海!

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    BioFach China中国国际有机食品博览会作为全球知名的有机贸易展德国BioFach在中国的子展,也是目前中国规模最大,规格最高、最具专业性的纯有机贸易博览会之一,所有展出的产品均具有国内或国际有机认证证书,为采购商和消费者提供了安全保证。

  13. BioFach China 2012绚丽多彩的有机世界

    Institute of Scientific and Technical Information of China (English)

    左琼莹

    2012-01-01

    第六届Bio Fach China中国国际有机食品博览会将于2012年5月24~2613在上海国际展览中心隆重召开,这将是继BioFach纽伦堡展之后全球有机产业迎来的又一场有机盛宴。此次展会将汇集更多知名品牌,更具视觉冲击的展台,超高品质的有机产品,引人入胜的创新研讨会主题.以及更为有趣的现场互动环节。

  14. BioFach China2011 五周年再创辉煌

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    2011年5月26日至28日,BioFach China迎来了她的五岁生日。来自33个国家及地区的14,613名有机产品贸易商见证了这迄今为止最成功的一届展会。与去年相比,这一数字增长达到了惊人的27%(2010年:11,526)。作为展会的主办方,德国纽伦堡会展公司为这份生日礼物感到欢欣鼓舞一持续增长的展商将展位预订一空,

  15. Laterale 10-fach-Biopsie der Prostata liefert bei Karzinomverdacht überlegene Detektionsraten

    Directory of Open Access Journals (Sweden)

    von Knobloch R

    2012-01-01

    Full Text Available Einleitung:Die Sextantenbiopsie der Prostata ist für eine verlässliche Karzinomdiagnostik nicht ausreichend. Vielerorts werden bereits bei der Erstbiopsie 12 Stanzen entnommen. In einer großen Serie von 10-fach-Biopsien unter bilateraler lokaler Leitungsanästhesie, wie bereits 2002 publiziert [1], überprüften wir die Qualität unserer Technik als Standard für die Erstbiopsie. Methode:Zwischen April 2005 und Dezember 2007 führten wir bei 736 Männern (Durchschnittsalter 67,5 ± 8,39 Jahre die Erstbiopsie der Prostata durch. Indikation für die Biopsie war entweder ein erhöhter PSA-Wert oder ein auffälliger Tastbefund. Bei allen Männern erfolgte die Biopsie der Prostata unter bilateraler lokaler Leitungsanästhesie. Es wurden nur Proben aus der peripheren Zone der Prostata unter transrektaler Ultraschallkontrolle entnommen. Ergebnisse:Durch die Biopsie wurde in 372 von 736 Fällen (50,5 % ein Karzinom identifiziert. Die Karzinomdetektionsrate war proportional zum PSA-Wert und indirekt proportional zum Organvolumen. Es zeigte sich eine eindeutige Korrelation zwischen der Anzahl positiver Stanzen bei der Biopsie mit dem pathologischen Stadium des Prostatektomiepräparates. 12 Männer (1,6 % mussten wegen akuter Prostatitis und 5 (0,7 % wegen rektaler Blutung wieder ins Krankenhaus eingewiesen werden. Von den 182 Patienten des Untersuchers R. v. K. wurde der durchschnittliche Schmerz der Biopsie mit 1,69 von maximal 10 angegeben. Die Detektions- und Komplikationsraten dieser Biopsietechnik unterschieden sich nicht nach Durchführung von Assistenz- oder Fachärzten. Schlussfolgerung: Die präsentierte Biopsietechnik liefert mit nur 10 Stanzen eine überlegene Detektionsrate und eine geringe Rate an Komplikationen. Sie sollte als Basis für die Definition eines Standards für die Erstbiopsie der Prostata bei Karzinomverdacht dienen.

  16. The Variation in Airflow Coefficient for Allison T56 Combustor Liners

    Science.gov (United States)

    1987-10-01

    Organisation Australian Airlines, Library Qantas Airways Limited Gas & Fuel Corporation of Vic., Manager Scientific Services SEC of Vic., Herman...0$D4CDIS 0 Fulfo)K.h FI.4ALSNT5 TMSRFOWCAAT4n 3.TH FIG. 4F ALISN 6OER FLOWATUJN CHRACTERSI Analysis of Allisons Drawing No 6876080 for manufacturing...fuel air ratio is decreased to 0.0205 which implies a turbine inlet temperature of 1055C. This analysis assumes that each atomiser admits the same

  17. Organic Sensory Information System – a European project that cares about organic taste at BioFach 2009

    OpenAIRE

    Wyss, Gabriela; Buchecker, Kirsten; Spiller, Achim; Schmid, Otto; Röder, Elke

    2009-01-01

    At the session at BioFach 2009 the following papers were presented: - ECROPOLIS (EU 7FP): Introduction and goals (Gabriela S. Wyss, co-ordinator, FiBL) - Sensory research and organic products (Kirsten Buchecker, WP leader sensory analysis, ttz) - Market potential of organic products through sensory research (Achim Spiller, WP leader market needs and solutions, University of Göttingen) - Regulatory framework and effect of taste (Otto Schmid, Co-WP leader market needs and solutions,...

  18. Medical specialist attendance in nursing homes [Beschreibung und Bewertung der fachärztlichen Versorgung von Pflegeheimbewohnern in Deutschland

    Directory of Open Access Journals (Sweden)

    Balzer, Katrin

    2013-04-01

    Full Text Available [english] The care in nursing homes was examined based on scientific studies. The analysis focuses on dementia and type II diabetes. There is evidence for deficits in the supply of medical specialist attendance to nursing home residents with these diseases in Germany. Compared with corresponding guidelines the medical care for nursing home residents may be too low or inadequate.[german] Es wird die Versorgung in Pflegeheimen auf Basis wissenschaftlicher Studien untersucht. Schwerpunkte der Analyse sind Demenz und Diabetes. Es gibt Hinweise auf fachärztliche Versorgungsmängel bei Pflegeheimbewohnern mit diesen Krankheiten in Deutschland. Verglichen mit entsprechenden Leitlinien bestehen mögliche Unter- bzw. Fehlversorgungen.

  19. Möglichkeiten und Grenzen von Innovationen im Lehrplan - evaluiert am Beispiel der Jahrgangsstufe 6 im Fach Mathematik

    OpenAIRE

    Lauer, Andreas

    2006-01-01

    Birgt der neue bayerische Lehrplan für das achtjährige Gymnasium aus dem Jahr 2004 Innovationen? Nehmen Lehrerinnen und Lehrer diese Neuerungen als solche wahr und werden sie von ihnen aufgenommen und letztlich auch umgesetzt? Mit diesen Leitfragen beschäftigt sich die, in Schulpädagogik angesiedelte, qualitative Studie mit dem Thema "Möglichkeiten und Grenzen von Innovationen im Lehrplan – evaluiert am Beispiel der Jahrgangsstufe 6 im Fach Mathematik". Dazu wurden sieben Mathematiklehrkräfte...

  20. The Allison V. Armour / William Henry Holmes 1895 Expedition to Mexico

    Directory of Open Access Journals (Sweden)

    Warren Haskin

    2001-11-01

    Full Text Available The foundation of the Field Museum's reputation as a place where serious science is practiced was laid by Allison V. Armour and William Henry Holmes in 1895, a little more than a year after the Museum was established. Looking back after a career of almost 60 years as an anthropologist, and having twice been honored as the outstanding practitioner in the field, Holmes described the trip to Mexico (the only expedition he led during his brief tenure as the Museum's first Curator of An­thropology as "one of the most gratifying and important events of my life." It was also one of the most important events in the history of anthropology at the Museum.

  1. TELEMED – Teaching Legal Medicine: Neukonzeption der Lehre im Fach Rechtsmedizin an der Universität des Saarlandes

    Directory of Open Access Journals (Sweden)

    Feiser, Judith

    2009-02-01

    Full Text Available Das Fach Rechtsmedizin ist Bestandteil der klinischen Lehre des Medizinstudiums. Im Zuge der Neuorientierung der medizinischen Ausbildung durch die Einführung der neuen ärztlichen Approbationsordnung wurde die Lehre am Institut für Rechtsmedizin der Universität des Saarlandes umstrukturiert. Dazu wurde das Lehrkonzept „TELEMED- Teaching Legal Medicine“ entwickelt, bestehend aus eLearning und Kleingruppenunterricht. Im Besonderen wurde bei der Gestaltung des neuen Lehrkonzeptes Wert darauf gelegt, die Lehre praxisbezogen zu gestalten. Aus diesem Anlass wurde am Ende des Wintersemesters (WS 2007/08 eine Evaluation mittels Fragebogen durchgeführt. An der Evaluation nahmen insgesamt 84 Studierende teil. Da das neue Lehrkonzept erstmals im WS 2007/08 Anwendung fand, konnte nicht mit früheren Semestern verglichen werden. Jedoch zeigten die Ergebnisse der Evaluation im Gesamten eine hohe Akzeptanz und positive Einschätzung des Konzeptes bei den Studierenden. Ferner ließ sich feststellen, dass die Verwendung von eLearning im Fach Rechtsmedizin einen großen Beitrag zur Umsetzung der praxisorientierten Lehre liefert.

  2. Natural Hazard Problem and Solution Definition in the News Media: the Case of Tropical Storm Allison

    Science.gov (United States)

    Lindquist, Eric; Mosher-Howe, Katrina

    2010-05-01

    Focusing events such as natural or technological disasters can have significant impacts on public policy and planning in both the near and long term. These impacts can manifest at different temporal scales ranging from the period of immediate attention and disaster relief through the period of recovery and reconstruction and beyond. These impacts and associated decisions can be studied in retrospect and understood as not only short-term reactions, but as long-term components of subsequent natural hazard planning and public policy. By studying in detail how an event was defined, and the policy and planning alternatives that were raised or recommended in response to a disaster event, we can better understand the role that disaster-related focusing events play in the long-term evolution of a community's public policy, infrastructural planning efforts, and responses to natural disasters. This paper will use a focusing event framework to explore the local and regional policy impacts over time of a major urban flood in Houston, Texas, Tropical Storm Allison. Tropical Storm Allison (TSA), dropped 36 inches of rain on Houston over a period of four days in early June 2001, and was responsible for 22 deaths, 70,000 flood damaged homes, and 5 billion in damage to the region. The primary data source for this effort is a database of 500 articles from the major regional newspaper, the Houston Chronicle, over the period of 2001 through 2008. These articles were coded for multiple variables, including, cause, effect and impact (financial and social), blame, problem and solution definition and solution acceptance). This paper focuses primarily on the measures of problem definition (how was TSA, as an event, defined in the media, for example, as an act of God, or as a result of poor planning or decision making, etc), and on solution definition (what solutions were proposed to mitigate or adapt to future storms of this magnitude, how were they linked to the definition of the problem

  3. Celebrating Queer Lesbian Desires with Dorothy Allison: From moral monstrosity to the beautiful materiality of the body

    Directory of Open Access Journals (Sweden)

    Mélanie Grué

    2016-01-01

    Using social and queer theory on domination, sexuality and gender, this contribution explores how the queer American author Dorothy Allison celebrates the vilified transgressive lesbian body. As, in the 1970s, the mainstream american feminist movement crystallized around the definition of an acceptable sexuality in the name of femininity, female sexual practices were standardized according to strict identity frames, carnal desire was denied, and transgressive lesbians who play with gender roles were defined as abject. In response to this extreme taming of the body, Allison interrogates the notions of masculinity and femininity, domination and submission in her exploration of sexual pleasure and traumatized sexuality. She celebrates the aggressiveness and masculinity of queer lesbianism, promotes the fluidity of gender roles, and asserts the primacy of the flesh,sensuality, and materiality in sexuality.

  4. Evaluation and Outlook on BioFach China 2009%有机食品博览会的评估分析及对策建议

    Institute of Scientific and Technical Information of China (English)

    王敏; 李显军; 袁敏芬

    2010-01-01

    本文基于对第三届中国国际有机食品博览会-BioFach China 2009参展商和观众的调查,从展会组织,宣传、展览视觉效果和服务几个方面分析了参展商和观众对BioFach China 20009的评估情况.提出的发展对策为加大宣传力度、做好展商观众组织、重视展览视觉效果和提高服务水平.

  5. Ein (halb-automatisiertes Prüfungstool für semesterbegleitende Prüfungen im Fach Biometrie (Q1 im Medizinstudium [A (semi-automatic tool for semester accompanying exams in the biometry course in medical studies

    Directory of Open Access Journals (Sweden)

    Muche, Rainer

    2013-05-01

    Full Text Available [english] During every summer term at Ulm University the obligatory course of biometry (Q1 is taught in a PC pool using the statistical software SAS Analyst. Short examinations are performed at each of the 6 course dates summing the results over the term. This examination principle has proved to be worthwhile, because a continuous learning of the students during the whole term can be achieved by this.Some problems have to be resolved before realization. Among others, the time problem within the exercise has to be solved, as well as the formal criteria which have to be met. In addition, more time will be needed for the correction, because all students get individual data for the exams and so a standardisation is not possible.To solve these problems we have implemented the following points into our examination tool:The new system has been developed with different software-tools, whereas the main aspects have been realized by the statistical software SAS as well as MS Office programmes MS Excel and MS Access.[german] Im Fach Medizinische Biometrie/Querschnittsfach Q1 an der Universität Ulm wird jeweils in jedem Sommersemester das Pflichtseminar in einem PC Pool anhand der Statistiksoftware SAS-Analyst gelehrt. Dieser Kurs soll semesterbegleitend an jedem der sechs Termine anhand von Kurztests abgeprüft werden. Diese Prüfungsform hat sich bewährt, da so eine kontinuierliche Mitarbeit der Studierenden über das gesamte Semester erreicht wird. Die Umsetzung dieser Vorgehensweise birgt allerdings einige Probleme: Unter anderem muss das Zeitproblem in der Übung gelöst sowie die Prüfungssituation formal eingehalten werden. Außerdem ergibt sich so ein Mehraufwand für die Korrektur, da jeder Studierende einen eigenen individuellen Datensatz bei der Prüfung bekommt und so keine Standardisierung bei manueller Korrektur auf Papierbasis möglich ist.Um diesen Problemen zu begegnen, haben wir in dem vorzustellenden Prüfungstool folgende Punkte

  6. Erosion Coatings for High-Temperature Polymer Composites: A Collaborative Project With Allison Advanced Development Company

    Science.gov (United States)

    Sutter, James K.

    2000-01-01

    composite (ASTM D 4541 95 "Pull Off Strength of Coatings"). Glenn and Allison Advanced Development Company collaborated to optimize erosion coatings for gas turbine fan and compressor applications. All the coating systems survived aggressive thermal cycling without spalling. During erosion tests (see the final photo), the most promising coating systems tested had Cr3C2-NiCr and WC-Co as the hard topcoats. In all cases, these coating systems performed significantly better than that with a TiN hard topcoat. When material depth (thickness) loss is considered, the Cr3C2-NiCr and WC-Co coating systems provided, on average, an erosion resistance 8.5 times greater than that for the uncoated PMR 15/T650 35 composite. Similarly, Cr3C2-NiCr and WC-Co coating systems adhered to the PMC substrate during tensile tests significantly better than systems containing a TiN topcoat. Differences in topcoats of Cr3C2-NiCr and WC-Co were determined by considering issues such as cost and environmental impact. The preferred erosion-resistant coating system for PMR 15/T650 35 has WC-Co as the hard topcoat. This system provides the following benefits in comparison to the coating system with Cr3C2-NiCr topcoat: lower powder material cost (15 to 20 percent), environmentally friendly materials (Cr3C2-NiCr is hazardous), and higher deposition yield (10 to 15 percent), which results in less waste.

  7. Diagnosing MS

    Science.gov (United States)

    ... a Local Support Group Ask an MS Navigator Edward M. Dowd Personal Advocate Program Connect with Peers ... Symptoms & Diagnosis Diagnosing MS Possible MS Clinically Isolated Syndrome (CIS) Newly Diagnosed Diagnosing Tools Other Conditions to ...

  8. Diagnosing MS

    Science.gov (United States)

    ... Informed d Corporate Support Corporate Partners National Teams Partnership Opportunities d Personal Stories Ambassadors & Familiar Faces Life ... FAQs Learn More What Causes MS? Learn More Definition of MS Learn More Clinically Isolated Syndrome (CIS) ...

  9. Pediatric MS

    Science.gov (United States)

    ... a Local Support Group Ask an MS Navigator Edward M. Dowd Personal Advocate Program Connect with Peers ... I Associated Myelopathy (HAM) Learn More Clinically Isolated Syndrome (CIS) Learn More Balo’s Disease Learn More Acute ...

  10. Osmium isotope of the Co-rich crust from seamount Allison, central Pacific and its use for determination of growth hiatus and growth age

    Institute of Scientific and Technical Information of China (English)

    MENG XianWei; LIU YanGuang; QU WenJun; SHI XueFa

    2008-01-01

    Based on its microstructure, Co-rich crust A1-1 from seamount Allison, central Pacific, was scraped at averaged interval of 1.3 mm to measure osmium isotopic composition, and subsequently to establish the 187Os/188Os profile of scraping section of the crust. By observing the variation of 187Os/188Os under 10Be chronology and matching it to the well-known seawater Os isotope evolution of the past 40 Ma,two growth hiatuses (H1 and H2) occurring in the periods respectively between 13.6 and 29.6 Ma and between 8 and 9.8 Ma in the crust were recognized. According to the two hiatuses, the dating scheme for each scraped layer of the crust was suggested. For the upper layers younger than 6.SMa, their growth ages were calibrated under 10Be chronology; for the lower layers older than 6.SMa, their growth ages were obtained from 187Os/188Os evaluation curve by linear interpolation. Hereby, the age for the most inner layer of the crust was determined to be 39.5 Ma. H1 and H2 exactly correspond to the boundary between phosphatization and non-phosphatization and volcanic ash layer in the crust, respectively.

  11. Osmium isotope of the Co-rich crust from seamount Allison, central Pacific and its use for determination of growth hiatus and growth age

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Based on its microstructure, Co-rich crust A1-1 from seamount Allison, central Pacific, was scraped at averaged interval of 1.3 mm to measure osmium isotopic composition, and subsequently to establish the 187Os/188Os profile of scraping section of the crust. By observing the variation of 187Os/188Os under 10Be chronology and matching it to the well-known seawater Os isotope evolution of the past 40 Ma, two growth hiatuses (H1 and H2) occurring in the periods respectively between 13.6 and 29.6 Ma and between 8 and 9.8 Ma in the crust were recognized. According to the two hiatuses, the dating scheme for each scraped layer of the crust was suggested. For the upper layers younger than 6.8Ma, their growth ages were calibrated under 10Be chronology; for the lower layers older than 6.8Ma, their growth ages were obtained from 187Os/188Os evaluation curve by linear interpolation. Hereby, the age for the most inner layer of the crust was determined to be 39.5 Ma. H1 and H2 exactly correspond to the boundary between phosphatization and non-phosphatization and volcanic ash layer in the crust, respectively.

  12. Late Paleocene-middle Eocene benthic foraminifera on a Pacific seamount (Allison Guyot, ODP Site 865): Greenhouse climate and superimposed hyperthermal events

    Science.gov (United States)

    Arreguín-Rodríguez, Gabriela J.; Alegret, Laia; Thomas, Ellen

    2016-03-01

    We investigated the response of late Paleocene-middle Eocene (~60-37.5 Ma) benthic foraminiferal assemblages to long-term climate change and hyperthermal events including the Paleocene-Eocene Thermal Maximum (PETM) at Ocean Drilling Program (ODP) Site 865 on Allison Guyot, a seamount in the Mid-Pacific Mountains. Seamounts are isolated deep-sea environments where enhanced current systems interrupt bentho-pelagic coupling, and fossil assemblages from such settings have been little evaluated. Assemblages at Site 865 are diverse and dominated by cylindrical calcareous taxa with complex apertures, an extinct group which probably lived infaunally. Dominance of an infaunal morphogroup is unexpected in a highly oligotrophic setting, but these forms may have been shallow infaunal suspension feeders, which were ecologically successful on the current-swept seamount. The magnitude of the PETM extinction at Site 865 was similar to other sites globally, but lower diversity postextinction faunas at this location were affected by ocean acidification as well as changes in current regime, which might have led to increased nutrient supply through trophic focusing. A minor hyperthermal saw less severe effects of changes in current regime, with no evidence for carbonate dissolution. Although the relative abundance of infaunal benthic foraminifera has been used as a proxy for surface productivity through bentho-pelagic coupling, we argue that this proxy can be used only in the absence of changes in carbonate saturation and current-driven biophysical linking.

  13. MS in Your Relationships

    Science.gov (United States)

    ... Disease T Cells d What Causes MS? Disproved Theories Viruses Clusters d Who Gets MS? Pediatric MS ... Health Unhealthy Habits Managing MS and Another Condition Aging with MS Anesthesia and Surgery Managing Your MS ...

  14. 中外有机食品参展商对展览视觉形象认知水平的比较研究——基于中国国际有机博览会BioFach China 2007参展商的调查%The Comparative Study of Perceptions of Visual Image Between Domestic and Overseas Exhibitors——A Survey of BioFach,China ,2007

    Institute of Scientific and Technical Information of China (English)

    王敏; 郭春敏; 熊静雯

    2008-01-01

    以中国国际有机食品博览会BioFach China 2007参展商为调查样本,通过评分赋值法和因子分析方法,分析中外参展商行为差异和对展览视觉形象的认知水平.结果表明,中国参展商整体认知水平低于境外参展商,行为受认知程度影响.境外参展商在参展理论、参展目的和对展览的重视程度等方面明显高于中国参展商.

  15. DEGAM-Leitlinien als App für Mobiltelefone – Einsatz, Anregungen und Nutzen für den Lernprozess von Studierenden im Fach Allgemeinmedizin [Smartphone Application of Primary Care Guidelines used in Education of Medical Students

    Directory of Open Access Journals (Sweden)

    Waldmann, Uta-Maria

    2013-02-01

    knowledge, particularly through its use in waiting periods and the attractive medium smartphone. However, the latter prevents a mandatory curricular use in compulsory courses, since not all students use smartphones. It is a meaningful addition to existing teaching materials and supports evidence-based teaching in Family Medicine and is suitable for use not only in university course teaching but also during clinical training. [german] Hintergrund und Fragestellung: Die Leitlinien der Deutschen Gesellschaft für Allgemeinmedizin (DEGAM zu häufigen und wichtigen Beratungsanlässen in der Hausarztpraxis sind ein zentraler Inhalt der Lehre im Fach Allgemeinmedizin. Durch die Autoren wurden sie als App für Mobiltelefone aufbereitet und stehen somit nun Hausärzten und Studierenden jederzeit zur Verfügung. Die vorliegende Studie untersucht die Fragestellung: Wie bewerten Studierende den Nutzen dieser Anwendung für ihren Lernprozess im Fach Allgemeinmedizin?Methodik: Die Kurzversionen der 15 DEGAM-Leitlinien wurden als (Smartphone-Betriebssystem-unabhängige Web-App mit Möglichkeit der Offline-Nutzung umgesetzt und Studierenden in Kurs, Blockpraktikum, Wahlfächern und PJ (Praktisches Jahr Allgemeinmedizin angeboten. Die Evaluation erfolgte durch eine strukturierte Befragung über die Feedbackfunktion der Moodle-Lernplattform www.elearning-allgemeinmedizin.de mit Likertskalen und Freitextkommentaren.Ergebnisse: Der Evaluations-Rücklauf kam von 14 (25% der 56 studentischen TesterInnen aus dem Kurs Allgemeinmedizin (9, dem Blockpraktikum (1, dem PJ (1 und Wahlfächern (4. Die App selbst sehen die Studierenden als Mehrwert zur Print/PDF-Version. Sie nutzen sie häufig und erfolgreich in Nischenzeiten und vor/während/nach Lehrveranstaltungen. Neben allgemeinem Interesse / Kennenlernen der Leitlinien und Lernen wird sie zum Nachschlagen konkreter (theoretischer Fragestellungen eingesetzt, weniger im Zusammenhang mit Patientenkontakten. Interesse und Kenntnis der Leitlinien wird

  16. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... Disease T Cells d What Causes MS? Disproved Theories Viruses Clusters d Who Gets MS? Pediatric MS ... Health Unhealthy Habits Managing MS and Another Condition Aging with MS Anesthesia and Surgery Managing Your MS ...

  17. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... Society Sign In In Your Area Donate Donate Search v What Is MS? Definition of MS What Causes MS? Who Gets MS? Multiple Sclerosis FAQs Types of MS Related Conditions Symptoms & Diagnosis MS Symptoms ...

  18. Das Fähnchentestat als neue Prüfungsform im Fach Anatomie an der Ludwig-Maximilians-Universität München [Tag test as a particular kind of examination in the dissection course

    Directory of Open Access Journals (Sweden)

    Adamczyk, Christopher

    2007-08-01

    Full Text Available [english] Background: In view of the continuously increasing number of beginners of medical students at the Ludwig-Maximilians-University (LMU, the traditional kind of the practically oral tests on the cadaver for the assessment in tests of anatomy has become no longer reliably and practically realisable. Material and Methods: As an alternative was an exam-course established, where the students have to pass in turn different stations with preparations and to work on relating tasks. We investigated the practicability, reliability and the students' acceptance of this form of testing. Results: In 7 parallel prepaired exam-courses, 930 students can be testet within 155 minutes with time and effort of 2 academic teachers and 32 student co-workers. The results show an adequate selectivity high reliability and apropriate difficulty. Results of a written evaluation of 442 students (49% show a high acceptance of this kind of testing. Summary: This kind of test represents an alternative, which has to be taken seriously, to the traditional form of anatomical tests. [german] Hintergrund: Angesichts der stetig steigenden Zahl (WS 06/07 n=930 an Studienanfängern der Medizin in München ist im Fach Anatomie die traditionelle Prüfungsform der praktischen, mündlichen Prüfung am Präparat für die Bewertung in den Testaten nicht mehr zuverlässig und praktikabel durchführbar. Material & Methoden: Als Alternative wurde ein Prüfungsparcours etabliert, in dem die Studierenden der Reihe nach unterschiedliche Stationen mit ausgelegten Präparaten durchlaufen und entsprechende Aufgaben bearbeiten. Wir untersuchten die Praktikabilität, Zuverlässigkeit und studentische Akzeptanz des Prüfungsformates. Ergebnisse: Durch sieben parallel aufgebaute Prüfungsparcours können 930 Studierende in 155 Minuten mit einem Betreuungsaufwand von zwei akademischen und 32 studentischen Mitarbeitern geprüft werden. Die Ergebnisse zeigen eine adäquate Trennschärfe, hohe Zuverl

  19. Progressive-Relapsing MS (PRMS)

    Science.gov (United States)

    ... a Local Support Group Ask an MS Navigator Edward M. Dowd Personal Advocate Program Connect with Peers ... relapsing MS (PRMS) Types of MS Clinically Isolated Syndrome (CIS) Relapsing-remitting MS (RRMS) Primary progressive MS ( ...

  20. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... Related Conditions Symptoms & Diagnosis MS Symptoms Diagnosing MS Possible MS Clinically Isolated Syndrome (CIS) Newly Diagnosed Diagnosing ... Myelitis d Symptoms & Diagnosis d Diagnosing MS d Possible MS d Clinically Isolated Syndrome (CIS) d Newly ...

  1. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... v What Is MS? Definition of MS What Causes MS? Who Gets MS? Multiple Sclerosis FAQs Types of MS Related Conditions Symptoms & Diagnosis ... Myelin Immune-Mediated Disease T Cells d What Causes MS? Disproved Theories ... Hispanics & Latino/as d Multiple Sclerosis FAQs d Types of MS Clinically Isolated Syndrome ( ...

  2. Frontalunterricht oder interaktive Gruppenarbeit? Ein Vergleich des Lernerfolgs und der studentischen Evaluation für das Fach Biochemie [Didactic lecture or interactive group discussion? A comparison of the learning success and the student evaluation in biochemistry

    Directory of Open Access Journals (Sweden)

    Kadmon, Martina

    2009-05-01

    Unterrichtsformen bisher nur wenig erprobt. Die vorliegende Studie wurde mit dem Ziel durchgeführt, herauszufinden, welchen Einfluss die Unterrichtsform auf den Wissenszuwachs und die studentische Beurteilung des Biochemie-Unterrichts hat. Methodik: Studierende des 4. Fachsemesters (n=421 wurden für eine Seminarveranstaltung in zwei Gruppen randomisiert. Die Kontrollgruppe erhielt konventionellen Frontalunterricht, die Studiengruppe erarbeitete sich dieselben Lerninhalte anhand konkreter Fragestellungen in interaktiven Arbeitsgruppen. Als Messinstrument zur Beurteilung des kognitiven Erfolges diente ein Wissenstest unmittelbar nach der Veranstaltung und nach 4-6 Wochen. Die Beurteilung der beiden Unterrichtsformen durch die Studierenden erfolgte anhand eines Fragebogens. Ergebnisse: Studierende, die Frontalunterricht erhielten, schnitten in einem ersten Wissenstest, direkt nach der Veranstaltung, signifikant besser ab als Studierende, die sich die Inhalte in interaktiven Gruppen selbst erarbeiteten. Im Wiederholungstest waren keine signifikanten Wissensunterschiede mehr messbar. In der Evaluation beurteilten Studierende, die Frontalunterricht erhielten, die Veranstaltung signifikant besser als diejenigen, die in Gruppen arbeiteten. Schlussfolgerung: Die schlechtere studentische Bewertung der interaktiven Unterrichtsform gegenüber Frontalunterricht in einem Biochemieseminar kann verschiedene Ursachen haben. Eine Ursache könnte die starke Orientierung des Faches an Faktenwissen sein. Dieses Wissen wurde nach Meinung der Studierenden - in dem in dieser Studie gegebenen Rahmen – vom Dozenten besser vermittelt als es in einer interaktiven Gruppenarbeit von Studierenden selbst erarbeitet werden konnte. Andere Ursachen könnten Prüfungsmethoden und curriculare Vorgaben sein.

  3. Relapsing-Remitting MS (RRMS)

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    Full Text Available ... Gets MS? Pediatric MS African Americans Hispanics & Latino/as d Multiple Sclerosis FAQs d Types of MS ... Clinicians d Treating MS d Comprehensive Care Developing a Healthcare Team Make the Most of Your Doctor ...

  4. Relapsing-Remitting MS (RRMS)

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    Full Text Available ... with MS d Diet, Exercise & Healthy Behaviors Diet & Nutrition Exercise Heat & Temperature Sensitivity Sleep Vaccinations Women's Health Unhealthy Habits Managing MS and Another Condition Aging with MS Anesthesia and Surgery Managing Your MS ...

  5. Relapsing-Remitting MS (RRMS)

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    Full Text Available ... Definition of MS Myelin Immune-Mediated Disease T Cells d What Causes MS? Disproved Theories Viruses Clusters ... Research News & Progress Research News ECTRIMS 2016 Stem Cells in MS Progressive MS Research Clinical Trials in ...

  6. Relapsing-Remitting MS (RRMS)

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    Full Text Available ... Definition of MS Myelin Immune-Mediated Disease T Cells d What Causes MS? Disproved Theories Viruses Clusters ... Research News & Progress Research News ECTRIMS 2016 Stem Cells in MS Progressive MS Research Clinical Trials in ...

  7. Relapsing-Remitting MS (RRMS)

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    Full Text Available ... T Cells d What Causes MS? Disproved Theories Viruses Clusters d Who Gets MS? Pediatric MS African ... d Find Programs & Services in Your Area d Living Well with MS d Diet, Exercise & Healthy Behaviors ...

  8. Relapsing-Remitting MS (RRMS)

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    Full Text Available ... Clinicians d Resources & Support d Library & Education Programs Email newsletter Resilience: Addressing the Challenges of MS Webinar & ... remitting MS (RRMS) Share this page Facebook Twitter Email Relapsing-remitting MS (RRMS) Relapsing-remitting MS (RRMS) ...

  9. Sensitivity of GC-EI/MS, GC-EI/MS/MS, LC-ESI/MS/MS, LC-Ag(+) CIS/MS/MS, and GC-ESI/MS/MS for analysis of anabolic steroids in doping control.

    Science.gov (United States)

    Cha, Eunju; Kim, Sohee; Kim, Ho Jun; Lee, Kang Mi; Kim, Ki Hun; Kwon, Oh-Seung; Lee, Jaeick

    2015-01-01

    This study compared the sensitivity of various separation and ionization methods, including gas chromatography with an electron ionization source (GC-EI), liquid chromatography with an electrospray ionization source (LC-ESI), and liquid chromatography with a silver ion coordination ion spray source (LC-Ag(+) CIS), coupled to a mass spectrometer (MS) for steroid analysis. Chromatographic conditions, mass spectrometric transitions, and ion source parameters were optimized. The majority of steroids in GC-EI/MS/MS and LC-Ag(+) CIS/MS/MS analysis showed higher sensitivities than those obtained with other analytical methods. The limits of detection (LODs) of 65 steroids by GC-EI/MS/MS, 68 steroids by LC-Ag(+) CIS/MS/MS, 56 steroids by GC-EI/MS, 54 steroids by LC-ESI/MS/MS, and 27 steroids by GC-ESI/MS/MS were below cut-off value of 2.0 ng/mL. LODs of steroids that formed protonated ions in LC-ESI/MS/MS analysis were all lower than the cut-off value. Several steroids such as unconjugated C3-hydroxyl with C17-hydroxyl structure showed higher sensitivities in GC-EI/MS/MS analysis relative to those obtained using the LC-based methods. The steroids containing 4, 9, 11-triene structures showed relatively poor sensitivities in GC-EI/MS and GC-ESI/MS/MS analysis. The results of this study provide information that may be useful for selecting suitable analytical methods for confirmatory analysis of steroids.

  10. Natalizumab in progressive MS

    DEFF Research Database (Denmark)

    Romme Christensen, Jeppe; Ratzer, Rikke; Börnsen, Lars;

    2014-01-01

    OBJECTIVE: Natalizumab inhibits the migration of systemic immune cells to the CNS and may be beneficial in progressive multiple sclerosis (MS). The objective of the study was to examine the effects of natalizumab in progressive MS. METHODS: In an open-label phase 2A study, 24 patients with progre......OBJECTIVE: Natalizumab inhibits the migration of systemic immune cells to the CNS and may be beneficial in progressive multiple sclerosis (MS). The objective of the study was to examine the effects of natalizumab in progressive MS. METHODS: In an open-label phase 2A study, 24 patients...

  11. Satzklammer in der Deutschen Fach- Und Wissenschaftssprache

    Directory of Open Access Journals (Sweden)

    Vita Banionytė

    2011-04-01

    Full Text Available Der Grund zum Besprechen dieses Themas ist die Tatsache, dass die Satzklammer eine typische Erscheinung der deutschen Sprache ist. Die Klammerkonstrungen. Im vorliegenden Beitrag wird die vielseitige Analyse der deutschen Klammerkonstruktiouktionen sind auch ein wichtiges typologisches Charakteristikum des Deutschen. Im Litauischen ist dagegen die Wortfolge ganz frei. Wegen der unterschiedlichen Eigenschaften der Wortfolge im Deutschen und im Litauischen entstehen für die Lerner Schwierigkeiten im Prozess des Verstehens und des Produzierens der fremdsprachigen Äußernen durchgeführt. Am Anfang werden die historischen Aspekte dieses syntaktischen Phänomens besprochen. Weiterhin wird ausführlich die Satzklammrer charakterisiert. Der Hauptziel der Arbeit ist es, die Schwierigkeiten zu zeigen, auf die die Lerner stoßen, und die Vorschläge darzulegen, mit derer Hilfe die festgestellten Schwierigkeiten überwunden werden können. Schlüsselwörter: Satzklammer, typologisches Charakteristikum, Verbalklammer, Lexikalklammer, Ausklammerung. Vita Banionytė. Sentence Framework in the Professional and Scientific German Language // Coactivity. Vilnius: Technika, 2010, Vol. 18, No. 2 , p. 5-15. Abstract. The article analyses sentence framework in the Professional and scientific German language. This topic is chosen to be analysed because of difficulties the students confront while translating speciality texts and learning to communicate in a foreign language. The essence of these difficulties is a different word order in the German and Lithuanian languages. The historical aspects of this syntactic phenomenon are discussed at the beginning of this article. Sentence framework is one of typological features of the German language. Later the characteristic of sentence framework is defined. The aim of this article is to consider difficulties confronting the learners of a foreign language and to provide the ways how to avoid them, e.g. 1 to choose a different predicate, 2 to make the middle of the sentence more understandable, transforming it into a different syntactic construction, 3 to take out certain parts of the sentence beyond the sentence framework. The conclusion is drawn that this taking out beyond the sentence framework is particularly characteristic for the professional and scientific German language. The main reasons for taking out certain parts of the sentence beyond the sentence framework are: 1 those parts are taken out which were forgotten while planning a sentence, 2 important parts of the sentence are taken out because of stylistic reasons, 3 taking out certain parts of the sentence is used in order to create denominative blocks. At the end of the article recommendations are provided how to start and how to finish the translation of the German sentence with the framework construction into the Lithuanian language.

  12. Analysis of eicosanoids by LC-MS/MS and GC-MS/MS: a historical retrospect and a discussion.

    Science.gov (United States)

    Tsikas, Dimitrios; Zoerner, Alexander A

    2014-08-01

    Eicosanoids are a large family that derives from arachidonic acid, i.e., eicosatetraenoic acid. Prominent members include prostaglandins, thromboxane and leukotrienes. They are biologically highly active lipid mediators and play multiple physiological roles. GC-MS/MS has played a pivotal role in the identification and quantification of eicosanoids in biological samples. This technology generated a solid knowledge of their analytical chemistry, biochemistry, physiology and pharmacology. Since about a decade, GC-MS and GC-MS/MS are increasingly displaced by the seemingly more simple, rapid and powerful LC-MS/MS in the area of instrumental analysis of physiological substances, drugs and their metabolites. In this article, we review and discuss LC-MS/MS methods published over the last decade from the perspective of the GC-MS/MS user. Our analysis revealed that the shift from the adult GC-MS/MS to the youthful emerging LC-MS/MS technology in eicosanoid analysis is associated with several important challenges. Known pitfalls and problematic issues discovered by eicosanoid pioneers by using GC-MS/MS are often ignored by LC-MS/MS users. Established reference values and intervals provided by GC-MS-based methods are not considered properly in developing and validating LC-MS/MS methods. Virtually, there is a belief in the unlimited capability of the LC-MS/MS technique in eicosanoid analysis, a thought that simulates analytical certainty. LC-MS/MS users should profit from the plethora of solid knowledge acquired from the use of GC-MS/MS in eicosanoid analysis in basic and clinical research.

  13. Living with Advanced MS

    Science.gov (United States)

    ... Read More Read More Resource Edward M. Dowd Personal Advocate Program The Edward M. Dowd Personal Advocate ... Connection About the Society Vision Careers Leadership Cultural Values Financials News Press Room MS Prevalence Charitable Ratings ...

  14. Relapsing-Remitting MS (RRMS)

    Science.gov (United States)

    ... Disease T Cells d What Causes MS? Disproved Theories Viruses Clusters d Who Gets MS? Pediatric MS ... as well as worsening (a confirmed increase in disability over a specified period of time following a ...

  15. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... Disease T Cells d What Causes MS? Disproved Theories Viruses Clusters d Who Gets MS? Pediatric MS ... as well as worsening (a confirmed increase in disability over a specified period of time following a ...

  16. Relapsing-Remitting MS (RRMS)

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    Full Text Available ... Disproved Theories Viruses Clusters d Who Gets MS? Pediatric MS African Americans Hispanics & Latino/as d Multiple ... Questions to Ask d Resources for Specific Populations Pediatric MS Support Veterans with Multiple Sclerosis d Find ...

  17. Relapsing-Remitting MS (RRMS)

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    Full Text Available ... of which the person is aware. What happens in RRMS? Relapsing-remitting MS is defined by inflammatory ... remitting MS (RRMS) Learn More Learn More Research in relapsing-remitting MS (RRMS) Learn More Learn More ...

  18. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... Awareness Join the Community Stay Informed Corporate Support d What Is MS? d Definition of MS Myelin Immune-Mediated Disease T Cells d What Causes MS? Disproved Theories Viruses Clusters d ...

  19. Relapsing-Remitting MS (RRMS)

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    Full Text Available ... Disease T Cells d What Causes MS? Disproved Theories Viruses Clusters d Who Gets MS? Pediatric MS ... of Distinction Lawry Circle Circle of Influence d Planned Giving d Other Ways to Give Donate by ...

  20. Relapsing-Remitting MS (RRMS)

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    Full Text Available ... of which the person is aware. What happens in RRMS? Relapsing-remitting MS is defined by inflammatory ... remitting MS (RRMS) Learn More Learn More Research in relapsing-remitting MS (RRMS) Learn More Learn More ...

  1. Relapsing-Remitting MS (RRMS)

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    Full Text Available ... with MS d Diet, Exercise & Healthy Behaviors Diet & Nutrition Exercise Heat & Temperature Sensitivity Sleep Vaccinations Women's Health Unhealthy Habits Managing MS and Another Condition Aging ...

  2. DOE/Allison ceramic vane effort

    Energy Technology Data Exchange (ETDEWEB)

    Wenglarz, R.; Browning, W.; Calcuttawala, S. [Allison Engine Co., Indianapolis, IN (United States)

    1995-10-01

    An objective of the Advanced Turbine Systems (ATS) program is to develop ultra-high efficiency gas turbine systems. Rotor inlet temperatures several hundred degrees greater than for the highest temperature current industrial engines will be required to meet the ATS objectives. Consequently, new technologies need to be developed and demonstrated to achieve the required ultra-high ATS efficiencies.

  3. Allison engine ATS program technical review

    Energy Technology Data Exchange (ETDEWEB)

    Mukavetz, D. [Allison Engine Co., Indianpolis, IN (United States)

    1995-10-01

    Gas turbines in industrial and utility applications can help meet future national and worldwide power generation requirements. Turbine systems burning natural gas offer environmentally sound and economical power generation and cogeneration. Since U.S. demand alone will require up to 15 gigawatts per year of new and replacement capacity after the year 2000, the availability of Advanced Turbine Systems (ATS) to fill a share of this need will save significant amounts of fuel and benefit the environment. Implementation of the ATS Program will also keep U.S. manufacturers on the cutting ledge of turbine technology for power generation applications and enhance the nation`s economic competitiveness.

  4. SAR by MS

    Institute of Scientific and Technical Information of China (English)

    HOFSTADLER; Steven

    2001-01-01

    RNAs have recently emerged as an exciting new target for small molecule therapeutics. Conventional HTS discovery strategies measuring disruption of RNAprotein interactions have proven unsuccessful. We describe a ligand-based drug discovery strategy that addresses the inherent difficulties RNA targets. The strategy is based on: 1) using a MS spectrometry (MS)-based assay to measure the affinity of compounds for a target; 2) performing competitive binding experiments and molecular modeling with the motifs to determine the binding site(s) of the ligands; 3) design and synthesis of derivatives of interesting binders to establish the linking sites; 4) identifying the appropriate linker group using MS; 5) fusing motifs into a more complex structure to afford higher affinity compounds. Example of applying this strategy to identify new classes of lead molecules with affinity and specificity for ribosomal RNA targets will be presented.  ……

  5. SAR by MS

    Institute of Scientific and Technical Information of China (English)

    HOFSTADLER Steven; LOWERY Kristin; DRADER Jared; DING Yili; JEFFERSON Elizabeth; SWAYZE Eric; GRIFFEY Rich; HE Yun

    2001-01-01

    @@ RNAs have recently emerged as an exciting new target for small molecule therapeutics. Conventional HTS discovery strategies measuring disruption of RNAprotein interactions have proven unsuccessful. We describe a ligand-based drug discovery strategy that addresses the inherent difficulties RNA targets. The strategy is based on: 1) using a MS spectrometry (MS)-based assay to measure the affinity of compounds for a target; 2) performing competitive binding experiments and molecular modeling with the motifs to determine the binding site(s) of the ligands; 3) design and synthesis of derivatives of interesting binders to establish the linking sites; 4) identifying the appropriate linker group using MS; 5) fusing motifs into a more complex structure to afford higher affinity compounds. Example of applying this strategy to identify new classes of lead molecules with affinity and specificity for ribosomal RNA targets will be presented.

  6. Determination of Glyphosate Levels in Breast Milk Samples from Germany by LC-MS/MS and GC-MS/MS

    NARCIS (Netherlands)

    Steinborn, Angelika; Alder, Lutz; Michalski, Britta; Zomer, Paul; Bendig, Paul; Martinez, Sandra Aleson; Mol, Hans G.J.; Class, Thomas J.; Costa Pinheiro, Nathalie

    2016-01-01

    This study describes the validation and application of two independent analytical methods for the determination of glyphosate in breast milk. They are based on liquid chromatography-tandem mass spectrometry (LC-MS/MS) and gas chromatography-tandem mass spectrometry (GC-MS/MS), respectively. For L

  7. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... Funding Deadlines Apply Online Funding Policies and Procedures Scientific Peer Reviewers Resources for Researchers d Professional Resource Center About MS Diagnosing MS Managing MS Resources for You and Your Practice Publications for Clinicians Publications for Your Patients MS Navigator ...

  8. Relapsing-Remitting MS (RRMS)

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    Full Text Available ... MS Relapsing-remitting MS (RRMS) Share this page Facebook Twitter Email Relapsing-remitting MS (RRMS) Relapsing-remitting ... Here Start Here Colophon Stay Informed Join Us Facebook Twitter LinkedIn YouTube Pinterest MS Connection About the ...

  9. Determination of Glyphosate Levels in Breast Milk Samples from Germany by LC-MS/MS and GC-MS/MS

    NARCIS (Netherlands)

    Steinborn, Angelika; Alder, Lutz; Michalski, Britta; Zomer, Paul; Bendig, Paul; Martinez, Sandra Aleson; Mol, Hans G.J.; Class, Thomas J.; Costa Pinheiro, Nathalie

    2016-01-01

    This study describes the validation and application of two independent analytical methods for the determination of glyphosate in breast milk. They are based on liquid chromatography-tandem mass spectrometry (LC-MS/MS) and gas chromatography-tandem mass spectrometry (GC-MS/MS), respectively. For L

  10. Relapsing-Remitting MS (RRMS)

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    Full Text Available ... MS Relapsing-remitting MS (RRMS) Share this page Facebook Twitter Email Relapsing-remitting MS (RRMS) Relapsing-remitting ... Here Start Here Colophon Stay Informed Join Us Facebook Twitter LinkedIn YouTube Pinterest MS Connection About the ...

  11. ICP-MS Workshop

    Energy Technology Data Exchange (ETDEWEB)

    Carman, April J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Eiden, Gregory C. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2014-11-01

    This is a short document that explains the materials that will be transmitted to LLNL and DNN HQ regarding the ICP-MS Workshop held at PNNL June 17-19th. The goal of the information is to pass on to LLNL information regarding the planning and preparations for the Workshop at PNNL in preparation of the SIMS workshop at LLNL.

  12. Human herpesviruses and MS

    DEFF Research Database (Denmark)

    Christensen, Tove

    2007-01-01

    Environmental factors operate on a background of genetic susceptibility in MS pathogenesis; the human herpesviruses (HHV) are likely candidates for such factors. HHV share a number of properties: they are almost ubiquitous, they are highly prevalent worldwide, they all cause latent infections...

  13. Childhood onset MS and MS during Pregnancy Rinze Frederik

    NARCIS (Netherlands)

    R.F. Neuteboom (Rinze)

    2012-01-01

    textabstractChapter 1, the introduction, summarizes current knowledge regarding two special and different situations in multiple sclerosis (MS): Childhood onset MS and MS during pregnancy. Chapter 2 describes the clinical (chapter 2.1-2.3) and biological studies (chapter 2.4-2.6) on pregnancy and M

  14. Childhood onset MS and MS during Pregnancy Rinze Frederik

    NARCIS (Netherlands)

    R.F. Neuteboom (Rinze)

    2012-01-01

    textabstractChapter 1, the introduction, summarizes current knowledge regarding two special and different situations in multiple sclerosis (MS): Childhood onset MS and MS during pregnancy. Chapter 2 describes the clinical (chapter 2.1-2.3) and biological studies (chapter 2.4-2.6) on pregnancy and M

  15. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... in Your Area Living Well with MS Diet, Exercise & Healthy Behaviors Emotional Well-Being Spiritual Well-Being ... Area d Living Well with MS d Diet, Exercise & Healthy Behaviors Diet & Nutrition Exercise Heat & Temperature Sensitivity ...

  16. Relapsing-Remitting MS (RRMS)

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    Full Text Available ... Life d Cognitive Health d Work, Home & Leisure Employment Insurance & Financial Information Staying Mobile Moving from Embarrassment ... Living with MS (.pdf) Download Brochure Focus on Employment (.pdf) Download Brochure Working with MS (.pdf) Download ...

  17. MS Disease-Modifying Medications

    Science.gov (United States)

    ... every 6 months Genentech (a member of the Roche Group) (first dose: 300 mg IV on day ... MS | National MS Society 26 Each of the pharmaceutical companies offers a program designed to help people ...

  18. Relapsing-Remitting MS (RRMS)

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    Full Text Available ... topics that may interest you Living with MS (.pdf) Download Brochure Focus on Employment (.pdf) Download Brochure Working with MS (.pdf) Download Brochure Taming Stress (.pdf) Download Brochure Multiple ...

  19. Relapsing-Remitting MS (RRMS)

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    Full Text Available ... Life d Cognitive Health d Work and Home Employment Insurance & Financial Information Staying Mobile Moving from Embarrassment ... Living with MS (.pdf) Download Brochure Focus on Employment (.pdf) Download Brochure Working with MS (.pdf) Download ...

  20. Relapsing-Remitting MS (RRMS)

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    Full Text Available ... Vitamin D How and Why Do Scientists Share Results d Research We Fund Stopping MS In Its ... MS Activist Take Action Current Advocacy Issues Advocacy Results Advocacy News d Raise Awareness d Join the ...

  1. Relapsing-Remitting MS (RRMS)

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    Full Text Available ... Area Living Well with MS Diet, Exercise & Healthy Behaviors Emotional Well-Being Spiritual Well-Being Cognitive Health ... Living Well with MS d Diet, Exercise & Healthy Behaviors Diet & Nutrition Exercise Heat & Temperature Sensitivity Sleep Vaccinations ...

  2. Relapsing-Remitting MS (RRMS)

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    Full Text Available ... bladder problems, and problems with cognition (learning and memory or information processing). People with progressive forms of MS are more likely ... MS (.pdf) Download Brochure Taming Stress (.pdf) ...

  3. Relapsing-Remitting MS (RRMS)

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    Full Text Available ... Travel and Recreation Managing MS and Another Condition Vaccinations Aging with MS Anesthesia and Surgery d Family ... 20s and 30s (although it can occur in childhood or later adulthood), while the onset of PPMS ...

  4. Relapsing-Remitting MS (RRMS)

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    Full Text Available ... Because the location of the damage is so variable, no two people have exactly the same symptoms. ... relapsing-remitting MS (RRMS) Learn More Learn More Research in relapsing-remitting MS (RRMS) Learn More Learn ...

  5. Relapsing-Remitting MS (RRMS)

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    Full Text Available ... Treating MS d Comprehensive Care Developing a Healthcare Team Make the Most of Your Doctor Visits Advance Medical Directives d Find an MS Care Provider Partners in MS Care d Managing Relapses Plasmapheresis d Rehabilitation Functional Electrical Stimulation (FES) ...

  6. Relapsing-Remitting MS (RRMS)

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    Full Text Available ... More Schilder's Disease Learn More The National MS Society is Here to Help Need More Information? We Are Here Our MS Navigators help identify ... you has recently been diagnosed, access our MS information and resources. Start Here Start Here ... Vision Careers Leadership Cultural Values Financials News Press ...

  7. MS Thornton and MS Gardner conduct DSO 410 on middeck

    Science.gov (United States)

    1983-01-01

    On middeck, Mission Specialist (MS) Thornton, his head surrounded by wiring and with electrodes attached to his face and forehead, controls instrument switch as MS Gardner, wearing headset, signals with his thumb. Procedures are part of Detailed Supplementary Objective (DSO) 410 - Audiometry. Forward lockers and starboard wall with field sequential (FS) crew cabin camera, sleep restraints, and net stowage bag appear in background.

  8. [Related substances in orlistat detected with UPLC-MS/MS].

    Science.gov (United States)

    Zhang, Ting-Ting; Ma, Chen

    2014-03-01

    The study aims to identify related substances in orlistat pharmaceutical substance from different production technologies. Advanced technologies including UPLC-QTOF-MS and UPLC-QTrap-MS were used and the structures or molecules of 10 kinds of related substances in orlistat were identified. The experimental data were valuable to the quality control and development of orlistat.

  9. Hydrogen Rearrangement Rules: Computational MS/MS Fragmentation and Structure Elucidation Using MS-FINDER Software.

    Science.gov (United States)

    Tsugawa, Hiroshi; Kind, Tobias; Nakabayashi, Ryo; Yukihira, Daichi; Tanaka, Wataru; Cajka, Tomas; Saito, Kazuki; Fiehn, Oliver; Arita, Masanori

    2016-08-16

    Compound identification from accurate mass MS/MS spectra is a bottleneck for untargeted metabolomics. In this study, we propose nine rules of hydrogen rearrangement (HR) during bond cleavages in low-energy collision-induced dissociation (CID). These rules are based on the classic even-electron rule and cover heteroatoms and multistage fragmentation. We evaluated our HR rules by the statistics of MassBank MS/MS spectra in addition to enthalpy calculations, yielding three levels of computational MS/MS annotation: "resolved" (regular HR behavior following HR rules), "semiresolved" (irregular HR behavior), and "formula-assigned" (lacking structure assignment). With this nomenclature, 78.4% of a total of 18506 MS/MS fragment ions in the MassBank database and 84.8% of a total of 36370 MS/MS fragment ions in the GNPS database were (semi-) resolved by predicted bond cleavages. We also introduce the MS-FINDER software for structure elucidation. Molecular formulas of precursor ions are determined from accurate mass, isotope ratio, and product ion information. All isomer structures of the predicted formula are retrieved from metabolome databases, and MS/MS fragmentations are predicted in silico. The structures are ranked by a combined weighting score considering bond dissociation energies, mass accuracies, fragment linkages, and, most importantly, nine HR rules. The program was validated by its ability to correctly calculate molecular formulas with 98.0% accuracy for 5063 MassBank MS/MS records and to yield the correct structural isomer with 82.1% accuracy within the top-3 candidates. In a test with 936 manually identified spectra from an untargeted HILIC-QTOF MS data set of human plasma, formulas were correctly predicted in 90.4% of the cases, and the correct isomer structure was retrieved at 80.4% probability within the top-3 candidates, including for compounds that were absent in mass spectral libraries. The MS-FINDER software is freely available at http://prime.psc.riken.jp/ .

  10. LC-MS based Metabolomics

    DEFF Research Database (Denmark)

    Magdenoska, Olivera

    with only 12C or 13C carbons were very low or even not measurable and showed minimal or no interference to the spiked amount of nonlabeled standards and their stable isotope-labeled internal standards (SIL-IS). Finally the developed IP-RP LC-MS method was coupled to a quadrupole time of flight (QTOF) MS...

  11. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... Review of Society's Research Programs d Careers d Leadership Board of Directors Senior Leadership Team Founder Sylvia Lawry d Cultural Values d ... Pinterest MS Connection About the Society Vision Careers Leadership Cultural Values Financials News Press Room MS Prevalence ...

  12. Determination of Glyphosate Levels in Breast Milk Samples from Germany by LC-MS/MS and GC-MS/MS.

    Science.gov (United States)

    Steinborn, Angelika; Alder, Lutz; Michalski, Britta; Zomer, Paul; Bendig, Paul; Martinez, Sandra Aleson; Mol, Hans G J; Class, Thomas J; Pinheiro, Nathalie Costa

    2016-02-17

    This study describes the validation and application of two independent analytical methods for the determination of glyphosate in breast milk. They are based on liquid chromatography-tandem mass spectrometry (LC-MS/MS) and gas chromatography-tandem mass spectrometry (GC-MS/MS), respectively. For LC-MS/MS, sample preparation involved an ultrafiltration followed by chromatography on an anion exchange column. The analysis by GC-MS/MS involved an extraction step, cleanup on a cation exchange column, and derivatization with heptafluorobutanol and trifluoroacetic acid anhydride. Both methods were newly developed for breast milk and are able to quantify glyphosate residues at concentrations as low as 1 ng/mL. The methods were applied to quantify glyphosate levels in 114 breast milk samples, which had been collected from August to September of 2015 in Germany. The mothers participated at their own request and thus do not form a representative sample. In none of the investigated samples were glyphosate residues above the limit of detection found.

  13. pepgrep: A tool for peptide MS/MS pattern matching.

    Science.gov (United States)

    Chernukhin, Igor

    2013-04-01

    Typically, detection of protein sequences in collision-induced dissociation (CID) tandem MS (MS2) dataset is performed by mapping identified peptide ions back to protein sequence by using the protein database search (PDS) engine. Finding a particular peptide sequence of interest in CID MS2 records very often requires manual evaluation of the spectrum, regardless of whether the peptide-associated MS2 scan is identified by PDS algorithm or not. We have developed a compact cross-platform database-free command-line utility, pepgrep, which helps to find an MS2 fingerprint for a selected peptide sequence by pattern-matching of modelled MS2 data using Peptide-to-MS2 scoring algorithm. pepgrep can incorporate dozens of mass offsets corresponding to a variety of post-translational modifications (PTMs) into the algorithm. Decoy peptide sequences are used with the tested peptide sequence to reduce false-positive results. The engine is capable of screening an MS2 data file at a high rate when using a cluster computing environment. The matched MS2 spectrum can be displayed by using built-in graphical application programming interface (API) or optionally recorded to file. Using this algorithm, we were able to find extra peptide sequences in studied CID spectra that were missed by PDS identification. Also we found pepgrep especially useful for examining a CID of small fractions of peptides resulting from, for example, affinity purification techniques. The peptide sequences in such samples are less likely to be positively identified by using routine protein-centric algorithm implemented in PDS. The software is freely available at http://bsproteomics.essex.ac.uk:8080/data/download/pepgrep-1.4.tgz.

  14. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... emergency has passed, such as temporary living assistance, medical equipment, medications, emotional support, or other challenges to ... Make the Most of Your Doctor Visits Advance Medical Directives d Find an MS Care Provider Partners ...

  15. Relapsing-Remitting MS (RRMS)

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    Full Text Available ... a Local Support Group Ask an MS Navigator Edward M. Dowd Personal Advocate Program Connect with Peers ... I Associated Myelopathy (HAM) Learn More Clinically Isolated Syndrome (CIS) Learn More Balo’s Disease Learn More Acute ...

  16. Primary-Progressive MS (PPMS)

    Science.gov (United States)

    ... a Local Support Group Ask an MS Navigator Edward M. Dowd Personal Advocate Program Connect with Peers ... I Associated Myelopathy (HAM) Learn More Clinically Isolated Syndrome (CIS) Learn More Balo’s Disease Learn More Acute ...

  17. Secondary-Progressive MS (SPMS)

    Science.gov (United States)

    ... a Local Support Group Ask an MS Navigator Edward M. Dowd Personal Advocate Program Connect with Peers ... I Associated Myelopathy (HAM) Learn More Clinically Isolated Syndrome (CIS) Learn More Balo’s Disease Learn More Acute ...

  18. Relapsing-Remitting MS (RRMS)

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    Full Text Available ... Information Advanced Care Needs Employment Resources for Specific Populations Find Programs & Services in Your Area Living Well ... Decisions Career Options Accommodations d Resources for Specific Populations Pediatric MS Support Veterans with Multiple Sclerosis d ...

  19. Relapsing-Remitting MS (RRMS)

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    Full Text Available ... Studies Participate in Genetic Studies Donate to Tissue Banks d Research News & Progress Research News ECTRIMS 2016 ... Brochure Working with MS (.pdf) Download Brochure Taming Stress (.pdf) Download Brochure Multiple Sclerosis and Your Emotions (. ...

  20. Relapsing-Remitting MS (RRMS)

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    Full Text Available ... with MS d Health and Wellness Diet & Nutrition Exercise Emotional Health Smoking Alcohol Heat & Temperature Sensitivity Travel ... Together, you can weigh the potential risks and benefits of other treatment options. If your symptoms have ...

  1. Relapsing-Remitting MS (RRMS)

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    Full Text Available ... Senior Leadership Team Founder Sylvia Lawry d Cultural Values d Financials Annual Reports Sources of Support d ... Connection About the Society Vision Careers Leadership Cultural Values Financials News Press Room MS Prevalence Charitable Ratings ...

  2. Relapsing-Remitting MS (RRMS)

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    Full Text Available ... Behaviors Emotional Well-Being Spiritual Well-Being Cognitive Health Work, Home & Leisure Relationships Research Participate in Research ... Nutrition Exercise Heat & Temperature Sensitivity Sleep Vaccinations Women's Health Unhealthy Habits Managing MS and Another Condition Aging ...

  3. Relapsing-Remitting MS (RRMS)

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    Full Text Available ... Find Support Advanced Care Needs Resources for Specific Populations Find Programs & Services in Your Area Living Well ... Services: Questions to Ask d Resources for Specific Populations Pediatric MS Support Veterans with Multiple Sclerosis d ...

  4. Relapsing-Remitting MS (RRMS)

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    Full Text Available ... Potentials (EP) d Other Conditions to Rule Out Lyme Disease Lupus Neuromyelitis Optica Acute Disseminated Encephalomyelitis (ADEM) d ... Trials in MS Wellness and Lifestyle Research Diet Vitamin D How and Why Do Scientists Share Results ...

  5. Relapsing-Remitting MS (RRMS)

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    Full Text Available ... Senior Leadership Team Founder Sylvia Lawry d Cultural Values d Financials Annual Reports Sources of Support d ... Connection About the Society Vision Careers Leadership Cultural Values Financials News Press Room MS Prevalence Charitable Ratings ...

  6. Relapsing-Remitting MS (RRMS)

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    Full Text Available ... assistance, medical equipment, medications, emotional support, or other challenges to your quality of life. Please call 1- ... Library & Education Programs Email newsletter Resilience: Addressing the Challenges of MS Webinar & Telelearning Program Momentum Magazine Educational ...

  7. Relapsing-Remitting MS (RRMS)

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    Full Text Available ... Online d Give in Honor or Memory d Workplace Giving d Employer Matching Gifts d Gifts of ... Brochure Working with MS (.pdf) Download Brochure Taming Stress (.pdf) Download Brochure Multiple Sclerosis and Your Emotions (. ...

  8. Relapsing-Remitting MS (RRMS)

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    Full Text Available ... Services in Your Area Living Well with MS Health and Wellness Family and Relationships Mobility & Accessibility Personal ... Peers One-on-One d Insurance & Financial Information Health Insurance and Medicare Disability Insurance Life and Long- ...

  9. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... bowel and bladder problems, and problems with cognition (learning and memory or information processing). People with progressive forms of MS are more likely to experience gradually worsening problems with walking and mobility, along ...

  10. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... that can occur in RRMS; however, each person's experience with RRMS will be unique. Following a relapse, ... progressive forms of MS are more likely to experience gradually worsening problems with walking and mobility, along ...

  11. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... Online d Give in Honor or Memory d Workplace Giving d Employer Matching Gifts d Gifts of ... For Professionals Researchers Physicians Nurses Rehabilitation Professionals Mental Health Professionals Health and Wellness Professionals What Is MS? ...

  12. Relapsing-Remitting MS (RRMS)

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    Full Text Available ... for Change Become an MS Activist Take Action Current Advocacy Issues Advocacy Results Advocacy News d Raise ... your healthcare provider can feel confident that the current treatment regimen is working effectively. How does RRMS ...

  13. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... activated immune cells cause small, localized areas of damage which produce the symptoms of MS . Because the location of the damage is so variable, no two people have exactly ...

  14. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... membranes surrounding nerve fibers in the central nervous system (CNS)), as well as the nerve fibers themselves. ... and problems with cognition (learning and memory or information processing). People with progressive forms of MS are ...

  15. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... Results d Research We Fund Stopping MS In Its Tracks Restoring What's Been Lost Ending the Disease ... are diagnosed in their 20s and 30s (although it can occur in childhood or later adulthood), while ...

  16. Relapsing-Remitting MS (RRMS)

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    Full Text Available ... a Healthcare Team Make the Most of Your Doctor Visits Advance Medical Directives d Find an MS ... Map Site Tour Contact Us For Professionals Researchers Physicians Nurses Rehabilitation Professionals Mental Health Professionals Health and ...

  17. Relapsing-Remitting MS (RRMS)

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    Full Text Available ... with MS d Health and Wellness Diet & Nutrition Exercise Emotional Health Smoking Sleep Alcohol Heat & Temperature Sensitivity ... Together, you can weigh the potential risks and benefits of other treatment options. If your symptoms have ...

  18. Relapsing-Remitting MS (RRMS)

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    Full Text Available ... the Challenges of MS Webinar & Telelearning Program Momentum Magazine Educational Videos Live Fully, Live Well Knowledge Is ... d Spiritual Well-Being Building Spirituality into Your Life d Cognitive Health d Work, Home & Leisure Employment ...

  19. Relapsing-Remitting MS (RRMS)

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    Full Text Available ... you and your MS care provider discuss your treatment options and expected outcomes. For example: If you ... will likely want to consider a more aggressive treatment approach than if there were no evidence of ...

  20. Relapsing-Remitting MS (RRMS)

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    Full Text Available ... Room Events at a Glance MS the Disease Public Service Announcements In the News Archives ... Apply Online Funding Policies and Procedures Scientific Peer Reviewers Resources for Researchers ...

  1. Relapsing-Remitting MS (RRMS)

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    Full Text Available ... Treating MS d Comprehensive Care Developing a Healthcare Team Make the Most of Your Doctor Visits Advance ... Stay Informed d Corporate Support Corporate Partners National Teams Partnership Opportunities d Personal Stories Ambassadors & Familiar Faces ...

  2. Relapsing-Remitting MS (RRMS)

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    Full Text Available ... Results d Research We Fund Stopping MS In Its Tracks Restoring What's Been Lost Ending the Disease ... are diagnosed in their 20s and 30s (although it can occur in childhood or later adulthood), while ...

  3. LC/MS and SFC/MS: will they replace GC/MS

    Energy Technology Data Exchange (ETDEWEB)

    Warner, M.

    1987-07-01

    Will LC/MS and SFC/MS eventually replace GC/MS as the method of choice for organic trace analysis. This question was addressed at a symposium organized by Richard Browner of the Georgia Institute of Technology at this year's Pittsburgh Conference in Atlantic City, NJ. The symposium, one of the best-attended technical sessions at this year's meeting, featured presentations by Browner, Ron Hites of Indiana University, Jack Henion of Cornell University, Dick Smith of Battelle's Pacific Northwest Laboratory, and Marvin Vestal of The University of Houston.

  4. Analysis of acrylamide by LC-MS/MS and GC-MS in processed Japanese foods.

    Science.gov (United States)

    Ono, H; Chuda, Y; Ohnishi-Kameyama, M; Yada, H; Ishizaka, M; Kobayashi, H; Yoshida, M

    2003-03-01

    Acrylamide concentrations in processed foods (63 samples covering 31 product types) from Japan were analysed by LC-MS/MS and GC-MS methods. The limit of detection and limit of quantification of acrylamide were 0.2 ng x ml(-1) (6 fmol) and 0.8 ng x ml(-1) (22 fmol), respectively, by LC-MS/MS, and those of 2,3-dibromopropionamide derived from acrylamide were 12 ng x ml(-1) (52 fmol) and 40 ng x ml(-1) (170 fmol), respectively, by GC-MS. Repeatability given as RSD was 1000 microg x kg(-1). The concentrations in non-whole potato-based snacks, rice crackers processed by grilling or frying, and candied sweet potatoes were lower compared with those in the potato crisps and the whole potato-based fried snacks. One of the whole potato-based fried snacks, however, showed low acrylamide concentration (instant precooked noodles and won-tons were <100 microg x kg(-1) with only one exception. Roasted barley grains for 'Mugi-cha' tea contained 200-600 microg x kg(-1) acrylamide.

  5. Disposable chromatography for a high-throughput nano-ESI/MS and nano-ESI/MS-MS platform.

    Science.gov (United States)

    Williams, Jason G; Tomer, Kenneth B

    2004-09-01

    High-throughput proteomics has typically relied on protein identification based on MALDI-MS peptide maps of proteolytic digests of 2D-gel-separated proteins. This technique, however, requires significant sequence coverage in order to achieve a high level of confidence in the identification. Tandem MS data have the advantage of requiring fewer peptides (2) for high confidence identification, assuming adequate MS/MS sequence coverage. MALDI-MS/MS techniques are becoming available, but can still be problematic because of the difficulty of inducing fragment ions of a singly charged parent ion. Electrospray ionization, however, has the advantage of generating multiply charged species that are more readily fragmented during MS/MS analysis. Two electrospray/tandem mass spectrometry-based approaches, nanovial-ESI-MS/MS and LC-MS/MS, are used for high throughput proteomics, but much less often than MALDI-MS and peptide mass fingerprinting. Nanovial introduction entails extensive manual manipulation and often shows significant chemical background from the in-gel digest. LC-MS has the advantages that the chemical background can be removed prior to analysis and the analytes are concentrated during the separation, resulting in more abundant analyte signals. On the other hand, LC-MS can often be time intensive. Here, we report the incorporation of on-line sample clean-up and analyte concentration with a high-throughput, chip-based, robotic nano-ESI-MS platform for proteomics studies.

  6. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available Emergency & Disaster Resources If you or a loved one have been affected—or may be affected—by a hurricane, ... Brochure Working with MS (.pdf) Download Brochure Taming Stress (.pdf) Download Brochure Multiple Sclerosis and Your Emotions (. ...

  7. Method-MS. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Skipperud, L.; Popic, J.M. (Norwegian Univ. of Life Science (UMB), Isotope Lab. (Norway)); Roos, P. (Technical Univ. of Denmark, Risoe National Lab. for Sustainable Energy, Roskilde (Denmark)); Salminen, S. (Univ. of Helsinki (UH) (Finland)); Nygren, U. (Swedish Defence Research Agency (FOI) (Sweden)); Sigmarsson, O.; Palsson, S.E. (Univ. of Iceland/Icelandic Radiation Protection Institute (Iceland))

    2011-05-15

    Radiometric determination methods, such as alpha spectrometry require long counting times when low activities are to be determined. Mass spectrometric techniques as Inductively Coupled Plasma Mass Spectrometry (ICP-MS), Thermal Ionisation Mass Spectrometry (TIMS) and Accelerator Mass Spectrometry (AMS) have shown several advantages compared to traditional methods when measuring long-lived radionuclides. Mass spectrometric methods for determination of very low concentrations of elemental isotopes, and thereby isotopic ratios, have been developed using a variety of ion sources. Although primarily applied to the determination of the lighter stable element isotopes and radioactive isotopes in geological studies, the techniques can equally well be applied to the measurement of activity concentrations of long-lived low-level radionuclides in various samples using 'isotope dilution' methods such as those applied in inductively coupled plasma mass spectrometry (ICP-MS). Due to the low specific activity of long-lived radionuclides, many of these are more conveniently detected using mass spectrometric techniques. Mass spectrometry also enables the individual determination of Pu-239 and Pu-240, which cannot be obtained by alpha spectrometry. Inductively Coupled Plasma Mass Spectrometry (ICP-MS) are rapidly growing techniques for the ultra-trace analytical determination of stable and long-lived isotopes and have a wide potential within environmental science, including ecosystem tracers and radio ecological studies. Such instrumentation, of course needs good radiochemical separation, to give best performance. The objectives of the project is to identify current needs and problems within low-level determination of long-lived radioisotopes by ICP-MS, to perform intercalibration and development and improvement of ICP-MS methods for the measurement of radionuclides and isotope ratios and to develop new methods based on modified separation chemistry applied to new

  8. Determination of drugs in hair using GC/MS/MS.

    Science.gov (United States)

    Uhl, M

    1997-01-17

    An important task for the forensic toxicologist and expert witness is the detection of the noxa in biological matrices. Because of this, the identification and quantification of residues of illegal drugs in human hair is still of growing interest. Utilizing the advantages of GC/MS/MS testing human hair is performed for most common drugs of abuse like heroin and other opioides, cocaine, cannabis and amphetamine derivatives. Analyzing hair specimens for substances that present a toxicological risk is another challenge. Several quality control parameters must be observed to avoid false positive or false negative results and to gain additional information. Blank sample, blank hair as well as the combined wash extracts are tested for the presence of the relevant compounds within every series. Careful evaluation of the findings can provide an approximate measure of the intensity of drug use in the majority of cases.

  9. Determination of paraquat in vegetables using HPLC-MS-MS.

    Science.gov (United States)

    Zou, Tingting; He, Pingli; Cao, Jingjing; Li, Zhen

    2015-02-01

    A simple, sensitive, reliable and economical method was developed for the determination of paraquat (a widely used herbicide) in four edible vegetables (cabbage, lettuce, spinach and Chinese cabbage) using high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS-MS). The samples were extracted with water under sonication and cleaned up by weak cation exchange solid-phase extraction. Chromatographic separation of paraquat was achieved on a hydrophilic interaction liquid chromatography column (2.1 × 100 mm, 3 µm) with a gradient program using 10 mM ammonium acetate in 0.1% formic acid and acetonitrile as mobile phase. The low salt concentration used in the eluting buffer ensured extended LC-MS analysis of paraquat in different matrices without the necessity of frequent source cleaning. The validity of the developed method was evaluated by spiking paraquat in four edible vegetables at 50 and 500 ng g(-1). Recovery ranged from 43.6 to 73.5%. The limit of detection is 0.94 ng g(-1). With the developed method, the kinetic of paraquat entering plant tissue was also evaluated.

  10. The World of Organic Agriculture at BioFach 2009

    OpenAIRE

    Willer, Helga; Sahota, Amarjit; Huber, Beate

    2009-01-01

    The Powerpoint presentations summarize three key chapters of the 2009 edition of 'The World of Organic Agriculture' - Results of the global survey on organic agriculture - The global market for organic food and drink - Standards and legislation update

  11. Analytical Method Details (MS): SE24_MS1 [Metabolonote[Archive

    Lifescience Database Archive (English)

    Full Text Available SE24_MS1 LC-FTICR-MS Analysis (Positive) LC, Agilent 1200 series (Agilent); MS, Sol...sample (1 uL) was analyzed using LC-FTICR-MS (LC, Agilent 1200 series; MS, Bruker Daltonics solarix 7.0 T).

  12. 24 CFR Appendix Ms-2 to Part 3500 - Appendix MS-2 to Part 3500

    Science.gov (United States)

    2010-04-01

    ... HOUSING AND URBAN DEVELOPMENT REAL ESTATE SETTLEMENT PROCEDURES ACT Pt. 3500, App. MS-2 Appendix MS-2 to... 24 Housing and Urban Development 5 2010-04-01 2010-04-01 false Appendix MS-2 to Part 3500 MS Appendix MS-2 to Part 3500 Housing and Urban Development Regulations Relating to Housing and...

  13. 24 CFR Appendix Ms-1 to Part 3500 - Appendix MS-1 to Part 3500

    Science.gov (United States)

    2010-04-01

    ... HOUSING AND URBAN DEVELOPMENT REAL ESTATE SETTLEMENT PROCEDURES ACT Pt. 3500, App. MS-1 Appendix MS-1 to... 24 Housing and Urban Development 5 2010-04-01 2010-04-01 false Appendix MS-1 to Part 3500 MS Appendix MS-1 to Part 3500 Housing and Urban Development Regulations Relating to Housing and...

  14. LC-MS systems for quantitative bioanalysis.

    Science.gov (United States)

    van Dongen, William D; Niessen, Wilfried M A

    2012-10-01

    LC-MS has become the method-of-choice in small-molecule drug bioanalysis (molecular mass Triple quadrupole MS is the established bioanalytical technique due to its unpreceded selectivity and sensitivity, but high-resolution accurate-mass MS is recently gaining ground due to its ability to provide simultaneous quantitative and qualitative analysis of drugs and their metabolites. This article discusses current trends in the field of bioanalytical LC-MS (until September 2012), and provides an overview of currently available commercial triple quadrupole MS and high-resolution LC-MS instruments as applied for the bioanalysis of small-molecule and biopharmaceutical drugs.

  15. The potential of combining ion trap/MS/MS and TOF/MS for identification of emerging contaminants

    Science.gov (United States)

    Ferrer, I.; Furlong, E.T.; Heine, C.E.; Thurman, E.M.

    2002-01-01

    The use of a method combining ion trap tandem mass spectrometry (MS/MS) and time of flight mass spectrometry (TOF/MS) for identification of emerging contaminates was discussed. The two tools together complemented each other in sensitivity, fragmentation and accurate mass determination. Liquid chromatography/electrospray ionization/ion-trap tandem mass spectrometry (LC/ESI/MS/MS), in positive ion mode of operation, was used to separate and identify specific compounds. Diagnostic fragment ions were obtained for a polyethyleneglycol(PEG) homolog by ion trap MS/MS, and fragments were measured by TOF/MS. It was observed that the combined method gave an exact mass measurement that differed from the calculated mass.

  16. Selenium speciation analysis of Misgurnus anguillicaudatus selenoprotein by HPLC-ICP-MS and HPLC-ESI-MS/MS

    Science.gov (United States)

    Analytical methods for selenium (Se) speciation were developed using high performance liquid chromatography (HPLC) coupled to either inductively coupled plasma mass spectrometry (ICP-MS) or electrospray ionization tandem mass spectrometry (ESI-MS/MS). Separations of selenomethionine (Se-Met) and sel...

  17. Molecular analysis of intact preen waxes of Calidris Canutus (Aves: Scolopacidae) by GC/MS and GC/MS/MS

    NARCIS (Netherlands)

    Sinninghe Damsté, J.S.; Dekker, M.H.A.; Piersma, T.

    2000-01-01

    The intact preen wax esters of the red knot Calidris canutus were studied with gas chromatography/mass spectrometry (GC/MS) and GC/MS/MS. In this latter technique, transitions from the molecular ion to fragment ions representing the fatty acid moiety of the wax esters were measured, providing additi

  18. Physical Exercise and MS Recommendations

    DEFF Research Database (Denmark)

    Dalgas, U; Ingemann-Hansen, T; Stenager, E

    2009-01-01

    The use of physical exercise programmes in the rehabilitation of patients with multiple sclerosis (MS) has been a controversial issue for many years. During the last decade, however, evidence from a number of studies has suggested that exercise is a safe and efficient way to induce improvements...... in a number of physiological functions, which ultimately can lead to functional improvements that have a positive effect on a patients daily life. The purpose of this review is, based on the existing research, to provide clinicians with some easily administrable recommendations for the application of exercise...

  19. Biomarker discovery by CE-MS enables sequence analysis via MS/MS with platform-independent separation.

    Science.gov (United States)

    Zürbig, Petra; Renfrow, Matthew B; Schiffer, Eric; Novak, Jan; Walden, Michael; Wittke, Stefan; Just, Ingo; Pelzing, Matthias; Neusüss, Christian; Theodorescu, Dan; Root, Karen E; Ross, Mark M; Mischak, Harald

    2006-06-01

    CE-MS is a successful proteomic platform for the definition of biomarkers in different body fluids. Besides the biomarker defining experimental parameters, CE migration time and molecular weight, especially biomarker's sequence identity is an indispensable cornerstone for deeper insights into the pathophysiological pathways of diseases or for made-to-measure therapeutic drug design. Therefore, this report presents a detailed discussion of different peptide sequencing platforms consisting of high performance separation method either coupled on-line or off-line to different MS/MS devices, such as MALDI-TOF-TOF, ESI-IT, ESI-QTOF and Fourier transform ion cyclotron resonance, for sequencing indicative peptides. This comparison demonstrates the unique feature of CE-MS technology to serve as a reliable basis for the assignment of peptide sequence data obtained using different separation MS/MS methods to the biomarker defining parameters, CE migration time and molecular weight. Discovery of potential biomarkers by CE-MS enables sequence analysis via MS/MS with platform-independent sample separation. This is due to the fact that the number of basic and neutral polar amino acids of biomarkers sequences distinctly correlates with their CE-MS migration time/molecular weight coordinates. This uniqueness facilitates the independent entry of different sequencing platforms for peptide sequencing of CE-MS-defined biomarkers from highly complex mixtures.

  20. MOMA GC-MS coupling

    Science.gov (United States)

    Buch, A.; Pinnick, V. T.; Grand, N.; Szopa, C.; Danell, R.; Lustrement, B.; Freissinet, C.; van Amerom, F. H.; Raulin, F.; Glavin, D. P.; Stalport, F.; Coll, P. J.; Arevalo, R. D.; Brinckerhoff, W. B.; Goesmann, F.; Mahaffy, P. R.

    2013-12-01

    The joint ESA-Roscosmos Exo-Mars-2018 rover mission seeks the signs of past or present life on Mars. The Mars Organic Molecule Analyzer (MOMA) aboard the ExoMars rover will be a key analytical tool in providing chemical (molecular) information from the solid samples, with particular focus on the characterization of organic content. Central to MOMA instrumentation is a gas chromatograph-mass spectrometer (GC-MS) which provides the unique ability to characterize a broad range of compounds allowing chemical analyses of volatile and non-volatile species. The Gas chromatograph and the oven have been built at LATMOS/LISA (France) and at MPS (Germany) respectively whereas the mass spectrometer has been built at the NASA Goddard Space Flight Center (USA). Both instruments have been tested separately first and have been coupled in order to test the efficiency of the future MOMA GC-MS instrument. The main objective of the second step has been to test the quantitative response of both instruments while they are coupled and to characterize the combined instrument detection limit for several compounds. A final experiment has been done in order to test the feasibility of the separation and detection of a mixture contained in a soil sample introduced in the MOMA oven.

  1. Treatment optimization in MS: Canadian MS Working Group updated recommendations.

    Science.gov (United States)

    Freedman, Mark S; Selchen, Daniel; Arnold, Douglas L; Prat, Alexandre; Banwell, Brenda; Yeung, Michael; Morgenthau, David; Lapierre, Yves

    2013-05-01

    The Canadian Multiple Sclerosis Working Group (CMSWG) developed practical recommendations in 2004 to assist clinicians in optimizing the use of disease-modifying therapies (DMT) in patients with relapsing multiple sclerosis. The CMSWG convened to review how disease activity is assessed, propose a more current approach for assessing suboptimal response, and to suggest a scheme for switching or escalating treatment. Practical criteria for relapses, Expanded Disability Status Scale (EDSS) progression and MRI were developed to classify the clinical level of concern as Low, Medium and High. The group concluded that a change in treatment may be considered in any RRMS patient if there is a high level of concern in any one domain (relapses, progression or MRI), a medium level of concern in any two domains, or a low level of concern in all three domains. These recommendations for assessing treatment response should assist clinicians in making more rational choices in their management of relapsing MS patients.

  2. The role of EBV in MS pathogenesis

    DEFF Research Database (Denmark)

    Christensen, Tove

    2006-01-01

    Environmental factors operate on a background of genetic susceptibility in the pathogenesis of MS. Human herpesviruses, notably Epstein-Barr virus (EBV), and human endogenous retroviruses are factors associated with MS. EBV association is found in epidemiological surveys where late EBV infection ....... EBV cannot stand alone as a causal factor of MS, but is likely to play an indirect role as an activator of the underlying disease process.......Environmental factors operate on a background of genetic susceptibility in the pathogenesis of MS. Human herpesviruses, notably Epstein-Barr virus (EBV), and human endogenous retroviruses are factors associated with MS. EBV association is found in epidemiological surveys where late EBV infection...

  3. The immortality of Ms Jones.

    Science.gov (United States)

    Gallagher, Timothy

    2014-07-01

    When I began my medical student clinical rotations, I quickly became overwhelmed by feelings of inadequacy. While the doctors around me conjured appropriate diagnoses and treatment approaches, I fumbled with the only tools I possessed: my time and a smile. It was only when I met the patient Ms Jones that I came to understand the potential impact of these simple tools. My encouragement became part of her recovery process. She gave me the confidence to construct this ability of comforting patients into a small platform of confidence from which I could safely venture to educate patients or suggest treatments to residents. It could be something that I could reliably fall back on in times of doubt and something I could pass along to other people I met. © 2014 Annals of Family Medicine, Inc.

  4. The Reduction of Smoke Emissions from Allison T56 Engines

    Science.gov (United States)

    1990-03-01

    Industry Aero-Space Technologies Australia,Manager/Librarian (2 copies) Ansett Airlines of Australia, Library Australian Airlines, Library Qantas Airways ...R EFER EN CES ................................................................................ 12 a APPENDIX 1. Analysis of Fuel Samples...50% increase in the mass emissions of smoke particles at that power setting. Further analysis of the information contained in Souza and Daley (1978

  5. PTR-MS and GC-MS Analyses of Sesquiterpenes

    Science.gov (United States)

    Rasmussen, R. A.; Geron, C.; Goldstein, A. H.; Holzinger, R.; Lee, A.

    2003-12-01

    Terpene hydrocarbons are ubiquitous compounds in the atmosphere. Frits Went, in 1960 suggested that the volatile organic emissions from plants especially the monoterpenes were responsible for the formation of the atmosphere's `blue haze'. Surveys of plant emissions using a Proton Transfer Reaction - Mass Spectrometer (PTR-MS) have shown that many species emit sesquiterpenes (Ssqt's) independent of emitting monoterpenes or isoprene. It is possible they are a comparable source of the organic micro-aerosols responsible for scattering the blue end of the spectrum, i.e. `blue haze' in addition to the monoterpenes as they have more rapid and complete reactions with ozone resulting in particles. Ambient concentrations of the terpenic hydrocarbons are site dependent, but are typically very low from a few to 1000 pptCv, except for isoprene which has summer mid-day median levels of 3 to 6 ppbCv. The sesquiterpenes are very difficult to measure in the atmosphere by conventional means but cubebene, copaene, bourbonene and alpha- and beta-caryophyllene are common foliage emissions. Direct measurements of isoprene, monoterpenes and sesquiterpenes over plant foliages with a PTR-MS were compared with captive samples of the air from the same plant foliages collected in Summa canisters. None of the biogenic organic emissions stored in the Summa canisters showed any significant losses due to wall effects. Neither did we observe that any of the processing steps were responsible for losses or internal molecular rearrangements. The reason for the stability and 100% recovery of these C5 to C15 olefinic compounds at room temperature is believed to be due to the water layer formed on the electropolished stainless steel walls of the canister under pressure at 30 psig. Ozone added to the test systems was observed to have an immediate effect on the sesquiterpenes at ambient levels. Measurements made this past summer at the Duke and Blodgett Research Forests again confirm that the ambient

  6. Profiling cytosine oxidation in DNA by LC-MS/MS.

    Science.gov (United States)

    Samson-Thibault, Francois; Madugundu, Guru S; Gao, Shanshan; Cadet, Jean; Wagner, J Richard

    2012-09-17

    Spontaneous and oxidant-induced damage to cytosine is probably the main cause of CG to TA transition mutations in mammalian genomes. The reaction of hydroxyl radical (·OH) and one-electron oxidants with cytosine derivatives produces numerous oxidation products, which have been identified in large part by model studies with monomers and short oligonucleotides. Here, we developed an analytical method based on LC-MS/MS to detect 10 oxidized bases in DNA, including 5 oxidation products of cytosine. The utility of this method is demonstrated by the measurement of base damage in isolated calf thymus DNA exposed to ionizing radiation in aerated aqueous solutions (0-200 Gy) and to well-known Fenton-like reactions (Fe(2+) or Cu(+) with H(2)O(2) and ascorbate). The following cytosine modifications were quantified as modified 2'-deoxyribonucleosides upon exposure of DNA to ionizing radiation in aqueous aerated solution: 5-hydroxyhydantoin (Hyd-Ura) > 5-hydroxyuracil (5-OHUra) > 5-hydroxycytosine (5-OHCyt) > 5,6-dihydroxy-5,6-dihydrouracil (Ura-Gly) > 1-carbamoyl-4,5-dihydroxy-2-oxoimidazolidine (Imid-Cyt). The total yield of cytosine oxidation products was comparable to that of thymine oxidation products (5,6-dihydroxy-5,6-dihydrothymine (Thy-Gly), 5-hydroxy-5-methylhydantotin (Hyd-Thy), 5-(hydroxymethyl)uracil (5-HmUra), and 5-formyluracil (5-ForUra)) as well as the yield of 8-oxo-7,8-dihydroguanine (8-oxoGua). The major oxidation product of cytosine in DNA was Hyd-Ura. In contrast, the formation of Imid-Cyt was a minor pathway of DNA damage, although it is the major product arising from irradiation of the monomers, cytosine, and 2'-deoxycytidine. The reaction of Fenton-like reagents with DNA gave a different distribution of cytosine derived products compared to ionizing radiation, which likely reflects the reaction of metal ions with intermediate peroxyl radicals or hydroperoxides. The analysis of the main cytosine oxidation products will help elucidate the complex

  7. The role of EBV in MS pathogenesis

    DEFF Research Database (Denmark)

    Christensen, Tove

    2006-01-01

    Environmental factors operate on a background of genetic susceptibility in the pathogenesis of MS. Human herpesviruses, notably Epstein-Barr virus (EBV), and human endogenous retroviruses are factors associated with MS. EBV association is found in epidemiological surveys where late EBV infection....... EBV cannot stand alone as a causal factor of MS, but is likely to play an indirect role as an activator of the underlying disease process....

  8. Analytical Method Details (MS): SE51_MS01 [Metabolonote[Archive

    Lifescience Database Archive (English)

    Full Text Available SE51_MS01 mQTL analysis UPLC-QTOF Premier (Waters) and UPLC-TQS (Waters) UPLC-QTOF-MS...(Matsuda et al., 2009; Sawada et al., 2009a). After cutting off the low intensity data of MS2Ts, 702 MS... the optimal collision energy for MS2Ts, collision induced dissociation fragmentation analyses at six energy...less than 10% (analytical replicates = 3). Finally, 342 SRM conditions for MS2Ts were successfully assigned ...into z-scores of binary logarithms after missing values were replaced with 0.1. T

  9. An improved method of sample preparation on AnchorChip targets for MALDI-MS and MS/MS and its application in the liver proteome project

    DEFF Research Database (Denmark)

    Zhang, Xumin; Shi, Liang; Shu, Shaokung

    2007-01-01

    An improved method for sample preparation for MALDI-MS and MS/MS using AnchorChip targets is presented. The method, termed the SMW method (sample, matrix wash), results in better sensitivity for peptide mass fingerprinting as well as for sequencing by MS/MS than previously published methods. The ...

  10. LC-MS/MS analysis of steroids in the clinical laboratory.

    Science.gov (United States)

    Keevil, Brian G

    2016-09-01

    Liquid chromatography-tandem mass spectrometry (LC-MS/MS) is a powerful tool that is changing the way we analyse steroids in the clinical laboratory. It is already opening up the field of steroid analysis in endocrinology and is providing new applications for individual steroids and panels of steroids in different clinical conditions. LC-MS/MS is now well-accepted technology and is increasingly being used to replace problematic immunoassay methods because of greater sensitivity and specificity. Improved sample preparation, modern chromatography methods, and sensitive, faster scanning mass spectrometers have all played a role in improving LC-MS/MS. LC-MS/MS is also playing a key role in improving the quality of assays through the development of reference measurement procedures, characterisation of reference materials and multi-site calibration programmes. There is increasing interest in multiplexing steroid assays into panels of diagnostic tests to aid and improve the diagnosis and monitoring of disease.

  11. MS/MS studies for the selective detection of isomeric biogenic VOCs using a Townsend Discharge Triple Quadrupole Tandem MS and a PTR-Linear Ion Trap MS

    Directory of Open Access Journals (Sweden)

    M. Müller

    2009-08-01

    Full Text Available We performed MS/MS investigations of biogenic volatile organic compounds (BVOC using a triple quadrupole tandem mass spectrometer (QqQ-MS equipped with a Townsend Discharge ion source and a Proton Transfer Reaction Linear Ion Trap (PTR-LIT mass spectrometer. Both instruments use H2O chemical ionization to produce protonated molecular ions. Here we report a study of the application of these instruments to determine methyl vinyl ketone (MVK and methacrolein (MACR and a series of monoterpenes (α-pinene, β-pinene, 3-carene, limonene, myrcene, ocimene and sesquiterpenes (humulene and farnesene. Both instruments achieved sub-ppb detection limits in the single MS mode and in the MS/MS mode for differentiating MVK and MACR. Collision induced dissociation (CID of protonated monoterpenes and sesquiterpenes was studied under the high-energy, single-to-few collision conditions of the QqQ-MS instrument and under the low-energy, multiple collision conditions of the PTR-LIT. Differences and similarities in the breakdown curves obtained are discussed. In addition, we performed MS4 of protonated limonene to illustrate the analytical power of the PTR-LIT. In spite of the progress we have made, the selective on-line mass-spectrometric detection of individual monoterpenes or sesquiterpenes in complex mixtures currently does not yet seem to be possible.

  12. LC-MS systems for quantitative bioanalysis

    NARCIS (Netherlands)

    Dongen, W.D. van; Niessen, W.M.A.

    2012-01-01

    LC-MS has become the method-of-choice in small-molecule drug bioanalysis (molecular mass <800 Da) and is also increasingly being applied as an alternative to ligand-binding assays for the bioanalytical determination of biopharmaceuticals. Triple quadrupole MS is the established bioanalytical techniq

  13. Label-Free Proteome Profiling of Carbapenem-Resistant Klebsiella pneumoniae LC-MS/MS

    Science.gov (United States)

    2016-12-12

    the sub-MIC doses of antibiotics was performed by using label-free quantitative mass spectrometry. Sample Processing Protocol The pellets were...were cleaned up with Stage-Tip prior to 1D-LC-MS/MS. 1 µg of tryptic digest was loaded in each LC-MS/MS analysis. Data Processing Protocol Raw data ...Taxonomy 272620) combined with common contaminants proteins. Data files (12 Pride.XML files) KP-DC-Bio1: Doxycycline- treated Klebsiella pneumoniae

  14. Ferro-based derivatizing agents for LC/MS an LC/EC/MS

    NARCIS (Netherlands)

    Seiwert, Bettina

    2007-01-01

    Within this thesis, the development and application of ferrocene-based derivatizing agents for LC/MS and LC/EC/MS is presented. The advantages of derivatization by ferrocenes are the similtaneous introduction of a mass tag and an electroactive group, which make them ideally suited for LC/MS and esp

  15. Recently developed GC/MS and LC/MS methods for determining NSAIDs in water samples.

    Science.gov (United States)

    Farré, M; Petrovic, M; Barceló, D

    2007-02-01

    Pharmaceuticals have become major targets in environmental chemistry due to their presence in aquatic environments (following incomplete removal in wastewater treatment or point-source contaminations), threat to drinking water sources and concern about their possible effects to wildlife and humans. Recently several methods have been developed for the determination of drugs and their metabolites in the lower nanogram per litre range, most of them using solid-phase extraction (SPE) or solid-phase microextraction (SPME), derivatisation and finally gas chromatography mass spectrometry (GC-MS), gas chromatography tandem mass spectrometry (GC-MS/MS) and liquid chromatography electrospray tandem mass spectrometry (LC-ES/MS/MS). Due to the elevated polarity of non-steroidal anti-inflamatory drugs (NSAIDs), analytical techniques based on either liquid chromatography coupled to mass spectrometry (LC-MS) and gas chromatography coupled to mass spectrometry (GC-MS) after a previous derivatisation step are essential. The most advanced aspects of current GC-MS, GC-MS/MS and LC-MS/MS methodologies for NSAID analysis are presented.

  16. Efficient Modeling of MS/MS Data for Metabolic Flux Analysis.

    Science.gov (United States)

    Tepper, Naama; Shlomi, Tomer

    2015-01-01

    Metabolic flux analysis (MFA) is a widely used method for quantifying intracellular metabolic fluxes. It works by feeding cells with isotopic labeled nutrients, measuring metabolite isotopic labeling, and computationally interpreting the measured labeling data to estimate flux. Tandem mass-spectrometry (MS/MS) has been shown to be useful for MFA, providing positional isotopic labeling data. Specifically, MS/MS enables the measurement of a metabolite tandem mass-isotopomer distribution, representing the abundance in which certain parent and product fragments of a metabolite have different number of labeled atoms. However, a major limitation in using MFA with MS/MS data is the lack of a computationally efficient method for simulating such isotopic labeling data. Here, we describe the tandemer approach for efficiently computing metabolite tandem mass-isotopomer distributions in a metabolic network, given an estimation of metabolic fluxes. This approach can be used by MFA to find optimal metabolic fluxes, whose induced metabolite labeling patterns match tandem mass-isotopomer distributions measured by MS/MS. The tandemer approach is applied to simulate MS/MS data in a small-scale metabolic network model of mammalian methionine metabolism and in a large-scale metabolic network model of E. coli. It is shown to significantly improve the running time by between two to three orders of magnitude compared to the state-of-the-art, cumomers approach. We expect the tandemer approach to promote broader usage of MS/MS technology in metabolic flux analysis.

  17. Analysis of Hydrolysis Reaction of N-Phosphorylphenylalanine by HPLC-ESI-MS/MS

    Institute of Scientific and Technical Information of China (English)

    CAO Shu-Xia; ZHANG Jian-Chen; LIAO Xin-Cheng; ZHAO Yu-Fen

    2003-01-01

    @@ Hydrolysis procedure of N-diisopropyloxyphosphoryl phenylalanine (DIPP-Phe) has been studied by HPLCESI-MS. The hydrolysis products and intermediate were identified by HPLC-ESI-MS/MS. The results showed that (HO)(i-PrO)P(O)Phe was intermediate in the hydrolysis process.

  18. Analytical Method Details (MS): SE15_MS1 [Metabolonote[Archive

    Lifescience Database Archive (English)

    Full Text Available SE15_MS1 LC-Orbitrap-MS ESI positive method 1 Agilent1100 HPLC (Agilent), LTQ-Orbitrap (Thermo Fisher Scient...ific) LC-Orbitrap-MS ESI Positive Harvested sample is frozen by liquid N2 and groun

  19. Metabolomics data normalization with EigenMS.

    Directory of Open Access Journals (Sweden)

    Yuliya V Karpievitch

    Full Text Available Liquid chromatography mass spectrometry has become one of the analytical platforms of choice for metabolomics studies. However, LC-MS metabolomics data can suffer from the effects of various systematic biases. These include batch effects, day-to-day variations in instrument performance, signal intensity loss due to time-dependent effects of the LC column performance, accumulation of contaminants in the MS ion source and MS sensitivity among others. In this study we aimed to test a singular value decomposition-based method, called EigenMS, for normalization of metabolomics data. We analyzed a clinical human dataset where LC-MS serum metabolomics data and physiological measurements were collected from thirty nine healthy subjects and forty with type 2 diabetes and applied EigenMS to detect and correct for any systematic bias. EigenMS works in several stages. First, EigenMS preserves the treatment group differences in the metabolomics data by estimating treatment effects with an ANOVA model (multiple fixed effects can be estimated. Singular value decomposition of the residuals matrix is then used to determine bias trends in the data. The number of bias trends is then estimated via a permutation test and the effects of the bias trends are eliminated. EigenMS removed bias of unknown complexity from the LC-MS metabolomics data, allowing for increased sensitivity in differential analysis. Moreover, normalized samples better correlated with both other normalized samples and corresponding physiological data, such as blood glucose level, glycated haemoglobin, exercise central augmentation pressure normalized to heart rate of 75, and total cholesterol. We were able to report 2578 discriminatory metabolite peaks in the normalized data (p<0.05 as compared to only 1840 metabolite signals in the raw data. Our results support the use of singular value decomposition-based normalization for metabolomics data.

  20. Metabolomics data normalization with EigenMS.

    Science.gov (United States)

    Karpievitch, Yuliya V; Nikolic, Sonja B; Wilson, Richard; Sharman, James E; Edwards, Lindsay M

    2014-01-01

    Liquid chromatography mass spectrometry has become one of the analytical platforms of choice for metabolomics studies. However, LC-MS metabolomics data can suffer from the effects of various systematic biases. These include batch effects, day-to-day variations in instrument performance, signal intensity loss due to time-dependent effects of the LC column performance, accumulation of contaminants in the MS ion source and MS sensitivity among others. In this study we aimed to test a singular value decomposition-based method, called EigenMS, for normalization of metabolomics data. We analyzed a clinical human dataset where LC-MS serum metabolomics data and physiological measurements were collected from thirty nine healthy subjects and forty with type 2 diabetes and applied EigenMS to detect and correct for any systematic bias. EigenMS works in several stages. First, EigenMS preserves the treatment group differences in the metabolomics data by estimating treatment effects with an ANOVA model (multiple fixed effects can be estimated). Singular value decomposition of the residuals matrix is then used to determine bias trends in the data. The number of bias trends is then estimated via a permutation test and the effects of the bias trends are eliminated. EigenMS removed bias of unknown complexity from the LC-MS metabolomics data, allowing for increased sensitivity in differential analysis. Moreover, normalized samples better correlated with both other normalized samples and corresponding physiological data, such as blood glucose level, glycated haemoglobin, exercise central augmentation pressure normalized to heart rate of 75, and total cholesterol. We were able to report 2578 discriminatory metabolite peaks in the normalized data (pmetabolomics data.

  1. Quantitative and qualitative determination of Liuwei Dihuang tablets by HPLC-UV-MS-MS.

    Science.gov (United States)

    Zhao, Xinfeng; Wang, Yue; Sun, Yuqing

    2007-09-01

    A method is developed for the analysis of allantoin, gallic acid, dihydromelittoside, loganin, paeoniflorin, benzoylpaeoniflorin, and paeonol in Liuwei Dihuang tablets by high-performance liquid chromatography (HPLC)-UV-mass spectrometry (MS)-MS. Gradient elution with methanol-acetonitrile-water-formic acid solvent system is employed in the HPLC-electrospray ionization-MS study. The positive-ion ESI mode is suitable for these compounds. The peaks of gallic acid, loganin, dihydromelittoside, paeoniflorin, benzoylpaeoniflorin, and paeonol are identified by their mass spectra and the fragments of their MS-MS spectra. Allantoin, gallic acid, loganin, paeoniflorin, and paeonol are simultaneously determined by UV detection at 210 nm for quantitative purposes.

  2. Venocentric lesions: an MRI marker of MS?

    Directory of Open Access Journals (Sweden)

    Matthew P. Quinn

    2013-07-01

    Full Text Available From the earliest descriptions of MS, the venocentric characteristic of plaques was noted. Recently, numerous MRI studies have proposed this finding as a prospective biomarker for MS, which might aid in differentiating MS from other diseases with similar MRI findings. High field MRI studies have shown that penetrating veins can be detected in most MS lesions using T2* weighted or susceptibility weighted imaging. Future studies must address the feasibility of imaging such veins in a clinically practical context. The specificity of this biomarker has been studied only in a limited capacity. Results in microangiopathic lesions are conflicting, whereas asymptomatic white matter hyperintensities as well as lesions of NMO are less frequently venocentric compared to MS plaques. Prospective studies have shown that the presence of venocentric lesions at an early clinical presentation is highly predictive of future MS diagnosis. This is very promising, but work remains to be done to confirm or exclude lesions of common MS mimics, such as ADEM, as venocentric. A number of technical challenges must be addressed before the introduction of this technique as a complementary tool in current diagnostic procedures.

  3. MS/MS networking guided analysis of molecule and gene cluster families.

    Science.gov (United States)

    Nguyen, Don Duy; Wu, Cheng-Hsuan; Moree, Wilna J; Lamsa, Anne; Medema, Marnix H; Zhao, Xiling; Gavilan, Ronnie G; Aparicio, Marystella; Atencio, Librada; Jackson, Chanaye; Ballesteros, Javier; Sanchez, Joel; Watrous, Jeramie D; Phelan, Vanessa V; van de Wiel, Corine; Kersten, Roland D; Mehnaz, Samina; De Mot, René; Shank, Elizabeth A; Charusanti, Pep; Nagarajan, Harish; Duggan, Brendan M; Moore, Bradley S; Bandeira, Nuno; Palsson, Bernhard Ø; Pogliano, Kit; Gutiérrez, Marcelino; Dorrestein, Pieter C

    2013-07-09

    The ability to correlate the production of specialized metabolites to the genetic capacity of the organism that produces such molecules has become an invaluable tool in aiding the discovery of biotechnologically applicable molecules. Here, we accomplish this task by matching molecular families with gene cluster families, making these correlations to 60 microbes at one time instead of connecting one molecule to one organism at a time, such as how it is traditionally done. We can correlate these families through the use of nanospray desorption electrospray ionization MS/MS, an ambient pressure MS technique, in conjunction with MS/MS networking and peptidogenomics. We matched the molecular families of peptide natural products produced by 42 bacilli and 18 pseudomonads through the generation of amino acid sequence tags from MS/MS data of specific clusters found in the MS/MS network. These sequence tags were then linked to biosynthetic gene clusters in publicly accessible genomes, providing us with the ability to link particular molecules with the genes that produced them. As an example of its use, this approach was applied to two unsequenced Pseudoalteromonas species, leading to the discovery of the gene cluster for a molecular family, the bromoalterochromides, in the previously sequenced strain P. piscicida JCM 20779(T). The approach itself is not limited to 60 related strains, because spectral networking can be readily adopted to look at molecular family-gene cluster families of hundreds or more diverse organisms in one single MS/MS network.

  4. MS/MS networking guided analysis of molecule and gene cluster families

    Science.gov (United States)

    Nguyen, Don Duy; Wu, Cheng-Hsuan; Moree, Wilna J.; Lamsa, Anne; Medema, Marnix H.; Zhao, Xiling; Gavilan, Ronnie G.; Aparicio, Marystella; Atencio, Librada; Jackson, Chanaye; Ballesteros, Javier; Sanchez, Joel; Watrous, Jeramie D.; Phelan, Vanessa V.; van de Wiel, Corine; Kersten, Roland D.; Mehnaz, Samina; De Mot, René; Shank, Elizabeth A.; Charusanti, Pep; Nagarajan, Harish; Duggan, Brendan M.; Moore, Bradley S.; Bandeira, Nuno; Palsson, Bernhard Ø.; Pogliano, Kit; Gutiérrez, Marcelino; Dorrestein, Pieter C.

    2013-01-01

    The ability to correlate the production of specialized metabolites to the genetic capacity of the organism that produces such molecules has become an invaluable tool in aiding the discovery of biotechnologically applicable molecules. Here, we accomplish this task by matching molecular families with gene cluster families, making these correlations to 60 microbes at one time instead of connecting one molecule to one organism at a time, such as how it is traditionally done. We can correlate these families through the use of nanospray desorption electrospray ionization MS/MS, an ambient pressure MS technique, in conjunction with MS/MS networking and peptidogenomics. We matched the molecular families of peptide natural products produced by 42 bacilli and 18 pseudomonads through the generation of amino acid sequence tags from MS/MS data of specific clusters found in the MS/MS network. These sequence tags were then linked to biosynthetic gene clusters in publicly accessible genomes, providing us with the ability to link particular molecules with the genes that produced them. As an example of its use, this approach was applied to two unsequenced Pseudoalteromonas species, leading to the discovery of the gene cluster for a molecular family, the bromoalterochromides, in the previously sequenced strain P. piscicida JCM 20779T. The approach itself is not limited to 60 related strains, because spectral networking can be readily adopted to look at molecular family–gene cluster families of hundreds or more diverse organisms in one single MS/MS network. PMID:23798442

  5. An On-Target Desalting and Concentration Sample Preparation Protocol for MALDI-MS and MS/MS Analysis

    DEFF Research Database (Denmark)

    Zhang, Xumin; Wang, Quanhui; Lou, Xiaomin;

    2012-01-01

    2DE coupled with MALDI-MS is one of the most widely used and powerful analytic technologies in proteomics study. The MALDI sample preparation method has been developed and optimized towards the combination of simplicity, sample-cleaning, and sample concentration since its introduction. Here we...... present a protocol of the so-called Sample loading, Matrix loading, and on-target Wash (SMW) method which fulfills the three criteria by taking advantage of the AnchorChip™ targets. Our method is extremely simple and no pre-desalting or concentration is needed when dealing with samples prepared from 2DE....... The protocol is amendable for automation and would pave the road for high-throughput MALDI-MS or MS/MS-based proteomics studies with guaranteed sensitivity and high identification rate. The method has been successfully applied to mouse liver proteome study and so far has been employed in other proteome studies...

  6. Urine screening with the MS-2.

    OpenAIRE

    Hoban, D J; Koss, J C; Gratton, C A; Ronald, A R

    1983-01-01

    A study was undertaken to evaluate the effectiveness of the MS-2 (Abbott Laboratories, Dallas, Tex.) in screening urine specimens in a large clinical laboratory. A total of 15,319 urine specimens (9,954 midstream specimens and 5,365 catheter specimens) were evaluated with the MS-2 and by a surface streak procedure. The study was conducted in two phases, differing in that phase II urine specimens were evaluated in the MS-2 by using a program software update (03.01). For midstream urine specime...

  7. Using the MMPB technique to confirm microcystin concentrations in water measured by ELISA and HPLC (UV, MS, MS/MS).

    Science.gov (United States)

    Foss, Amanda J; Aubel, Mark T

    2015-09-15

    Microcystins have been detected in raw and finished drinking water using a variety of techniques, including assays (immunoassay, phosphatase inhibition) and HPLC (UV, MS/(MS)). The principal challenge to microcystin analysis is accounting for the over 150 variants that have been described. A confirmatory individual variant HPLC analysis is prone to under-reporting total microcystins due to method specificity. One method that allows for total microcystin quantitation is the MMPB technique. In this study, water samples with native microcystins were oxidized to cleave the Adda moiety, common to all microcystin variants. LC-MS/MS analysis was conducted on the subsequent MMPB (3-methoxy-2-methyl-4-phenylbutyric acid) molecule and calibrated using a certified reference standard (microcystin-LR) and 4-phenylbutyric acid. Total microcystin concentrations from MMPB were compared to Adda ELISA and individual variant analyses (LC-UV, LC-MS/(MS)). Variants of microcystin, including [DAsp(3)]MC-RR, [Dha(7)]MC-RR, MC-RR, MC-YR, MC-LR, [DAsp(3)]MC-LR, [Dha(7)]MC-LR, MC-WR, MC-LA, and MC-LY were detected and quantified in samples. The individual variant analyses did not account for total microcystins present in samples, as indicated by ELISA and MMPB data. Results demonstrated the MMPB technique is a simple and valuable approach to confirm ELISA data when analyzing microcystins, with method detection limits of 0.05 μg L(-1) for total microcystins.

  8. In Vivo Metabolism Study of Xiamenmycin A in Mouse Plasma by UPLC-QTOF-MS and LC-MS/MS

    Directory of Open Access Journals (Sweden)

    Feng Lei

    2015-01-01

    Full Text Available Xiamenmycin A is an antifibrotic leading compound with a benzopyran skeleton that is isolated from mangrove-derived Streptomyces xiamenensis. As a promising small molecule for fibrotic diseases, less information is known about its metabolic characteristics in vivo. In this study, the time-course of xiamenmycin A in mouse plasma was investigated by relative quantification. After two types of administration of xiamenmycin A at a single dose of 10 mg/kg, the plasma concentrations were measured quantitatively by LC-MS/MS. The dynamic changes in the xiamenmycin A concentration showed rapid absorption and quick elimination in plasma post-administration. Four metabolites (M1–M4 were identified in blood by UPLC-QTOF-MS, and xiamenmycin B (M3 is the principal metabolite in vivo, as verified by comparison of the authentic standard sample. The structures of other metabolites were identified based on the characteristics of their MS and MS/MS data. The newly identified metabolites are useful for understanding the metabolism of xiamenmycin A in vivo, aiming at the development of an anti-fibrotic drug candidate for the therapeutic treatment of excessive fibrotic diseases.

  9. Significance of MRI Perivascular Spaces in MS

    Directory of Open Access Journals (Sweden)

    J Gordon Millichap

    2008-10-01

    Full Text Available The role of perivascular Virchow-Robin spaces was investigated in 45 multiple sclerosis (MS patients and 30 healthy controls, in a study at Charite-Universitaetsmedizin Berlin, and Goethe University, Frankfurt.

  10. Dealing with MS in Your Important Relationships

    Science.gov (United States)

    ... Matters Carepartners d Library & Education Programs Email newsletter Resilience: Addressing the Challenges of MS Webinar & Telelearning Program ... Health and Wellness Diet & Nutrition Exercise Emotional Health Smoking Alcohol Heat & Temperature Sensitivity Travel and Recreation Managing ...

  11. Semi-automated quantification of methylmalonic acid in human serum by LC-MS/MS.

    Science.gov (United States)

    Nelson, Dick; Xu, Ning; Carlson, Joyce

    2012-10-01

    Methylmalonic acid (MMA), a sensitive biomarker of functional vitamin B12 deficiency, is commonly determined by gas chromatography-mass spectrometry (GC-MS) or liquid chromatography-tandem mass spectrometry (LC-MS/MS) methods using manual extraction and derivatization of MMA to reduce polarity prior to separation. In the present study we introduce a semi-automated extraction on a strong anion exchanger, HPLC separation on a BEH-amide column to separate serum MMA from its abundant isoform, succinic acid, followed by MS/MS detection and quantification. The extraction of MMA plus internal standard provides full recovery and the method is linear between 0.03 μmol/L and 20.0 μmol/L (r(2) = 1.0) with intra-and inter-assay imprecision of 2.2%. Agreement with other laboratories has been demonstrated in external proficiency testing. Compared to both conventional GC-MS and LC-MS/MS methods, the correlation is r(2) > 0.99. The use of robotic pipetting, elimination of derivatization and improved separation by the BEH-amide column combined with HILIC chromatographic conditions significantly improve sample throughput compared to conventional methods. Using a single pipetting robot and LC-MS/MS instrument, this method is currently performing 180 analyses per day from 10 regional hospitals and several additional distant sites.

  12. Prioritization of putative metabolite identifications in LC-MS/MS experiments using a computational pipeline.

    Science.gov (United States)

    Zhou, Bin; Xiao, Jun Feng; Ressom, Habtom W

    2013-01-01

    One of the major bottle-necks in current LC-MS-based metabolomic investigations is metabolite identification. An often-used approach is to first look up metabolites from databases through peak mass, followed by verification of the obtained putative identifications using MS/MS data. However, the mass-based search may provide inappropriate putative identifications when the observed peak is from isotopes, fragments, or adducts. In addition, a large fraction of peaks is often left with multiple putative identifications. To differentiate these putative identifications, manual verification of metabolites through comparison between biological samples and authentic compounds is necessary. However, such experiments are laborious, especially when multiple putative identifications are encountered. It is desirable to use computational approaches to obtain more reliable putative identifications and prioritize them before performing experimental verification of the metabolites. In this article, a computational pipeline is proposed to assist metabolite identification with improved metabolome coverage and prioritization capability. Multiple publicly available software tools and databases, along with in-house developed algorithms, are utilized to fully exploit the information acquired from LC-MS/MS experiments. The pipeline is successfully applied to identify metabolites on the basis of LC-MS as well as MS/MS data. Using accurate masses, retention time values, MS/MS spectra, and metabolic pathways/networks, more appropriate putative identifications are retrieved and prioritized to guide subsequent metabolite verification experiments.

  13. Multi-Segment Direct Inject nano-ESI-LTQ-FT-ICR-MS/MS For Protein Identification.

    Science.gov (United States)

    Chen, Jing; Canales, Lorena; Neal, Rachel E

    2011-07-07

    Reversed phase high performance liquid chromatography (HPLC) interfaced to electrospray tandem mass spectrometry (MS/MS) is commonly used for the identification of peptides from proteolytically cleaved proteins embedded in a polyacrylamide gel matrix as well as for metabolomics screening. HPLC separations are time consuming (30-60 min average), costly (columns and mobile phase reagents), and carry the risk of column carry over between samples. The use of a chip-based nano-ESI platform (Advion NanoMate) based on replaceable nano-tips for sample introduction eliminates sample cross-contamination, provides unchanging sample matrix, and enhances spray stability with attendant increases in reproducibility. Recent papers have established direct infusion nano-ESI-MS/MS utilizing the NanoMate for protein identification of gel spots based on full range MS scans with data dependent MS/MS. In a full range scan, discontinuous ion suppression due to sample matrix can impair identification of putative mass features of interest in both the proteomic and metabolomic workflows. In the current study, an extension of an established direct inject nano-ESI-MS/MS method is described that utilizes the mass filtering capability of an ion-trap for ion packet separation into four narrow mass ranges (50 amu overlap) with segment specific dynamic data dependent peak inclusion for MS/MS fragmentation (total acquisition time of 3 minutes). Comparison of this method with a more traditional nanoLC-MS/MS based protocol utilizing solvent/sample stream splitting to achieve nanoflow demonstrated comparable results for protein identification from polyacrylamide gel matrices. The advantages of this method include full automation, lack of cross-contamination, low cost, and high throughput.

  14. Expert System for Computer-assisted Annotation of MS/MS Spectra*

    Science.gov (United States)

    Neuhauser, Nadin; Michalski, Annette; Cox, Jürgen; Mann, Matthias

    2012-01-01

    An important step in mass spectrometry (MS)-based proteomics is the identification of peptides by their fragment spectra. Regardless of the identification score achieved, almost all tandem-MS (MS/MS) spectra contain remaining peaks that are not assigned by the search engine. These peaks may be explainable by human experts but the scale of modern proteomics experiments makes this impractical. In computer science, Expert Systems are a mature technology to implement a list of rules generated by interviews with practitioners. We here develop such an Expert System, making use of literature knowledge as well as a large body of high mass accuracy and pure fragmentation spectra. Interestingly, we find that even with high mass accuracy data, rule sets can quickly become too complex, leading to over-annotation. Therefore we establish a rigorous false discovery rate, calculated by random insertion of peaks from a large collection of other MS/MS spectra, and use it to develop an optimized knowledge base. This rule set correctly annotates almost all peaks of medium or high abundance. For high resolution HCD data, median intensity coverage of fragment peaks in MS/MS spectra increases from 58% by search engine annotation alone to 86%. The resulting annotation performance surpasses a human expert, especially on complex spectra such as those of larger phosphorylated peptides. Our system is also applicable to high resolution collision-induced dissociation data. It is available both as a part of MaxQuant and via a webserver that only requires an MS/MS spectrum and the corresponding peptides sequence, and which outputs publication quality, annotated MS/MS spectra (www.biochem.mpg.de/mann/tools/). It provides expert knowledge to beginners in the field of MS-based proteomics and helps advanced users to focus on unusual and possibly novel types of fragment ions. PMID:22888147

  15. Multi-Segment Direct Inject nano-ESI-LTQ-FT-ICR-MS/MS For Protein Identification

    Directory of Open Access Journals (Sweden)

    Neal Rachel E

    2011-07-01

    Full Text Available Abstract Reversed phase high performance liquid chromatography (HPLC interfaced to electrospray tandem mass spectrometry (MS/MS is commonly used for the identification of peptides from proteolytically cleaved proteins embedded in a polyacrylamide gel matrix as well as for metabolomics screening. HPLC separations are time consuming (30-60 min average, costly (columns and mobile phase reagents, and carry the risk of column carry over between samples. The use of a chip-based nano-ESI platform (Advion NanoMate based on replaceable nano-tips for sample introduction eliminates sample cross-contamination, provides unchanging sample matrix, and enhances spray stability with attendant increases in reproducibility. Recent papers have established direct infusion nano-ESI-MS/MS utilizing the NanoMate for protein identification of gel spots based on full range MS scans with data dependent MS/MS. In a full range scan, discontinuous ion suppression due to sample matrix can impair identification of putative mass features of interest in both the proteomic and metabolomic workflows. In the current study, an extension of an established direct inject nano-ESI-MS/MS method is described that utilizes the mass filtering capability of an ion-trap for ion packet separation into four narrow mass ranges (50 amu overlap with segment specific dynamic data dependent peak inclusion for MS/MS fragmentation (total acquisition time of 3 minutes. Comparison of this method with a more traditional nanoLC-MS/MS based protocol utilizing solvent/sample stream splitting to achieve nanoflow demonstrated comparable results for protein identification from polyacrylamide gel matrices. The advantages of this method include full automation, lack of cross-contamination, low cost, and high throughput.

  16. Expert system for computer-assisted annotation of MS/MS spectra.

    Science.gov (United States)

    Neuhauser, Nadin; Michalski, Annette; Cox, Jürgen; Mann, Matthias

    2012-11-01

    An important step in mass spectrometry (MS)-based proteomics is the identification of peptides by their fragment spectra. Regardless of the identification score achieved, almost all tandem-MS (MS/MS) spectra contain remaining peaks that are not assigned by the search engine. These peaks may be explainable by human experts but the scale of modern proteomics experiments makes this impractical. In computer science, Expert Systems are a mature technology to implement a list of rules generated by interviews with practitioners. We here develop such an Expert System, making use of literature knowledge as well as a large body of high mass accuracy and pure fragmentation spectra. Interestingly, we find that even with high mass accuracy data, rule sets can quickly become too complex, leading to over-annotation. Therefore we establish a rigorous false discovery rate, calculated by random insertion of peaks from a large collection of other MS/MS spectra, and use it to develop an optimized knowledge base. This rule set correctly annotates almost all peaks of medium or high abundance. For high resolution HCD data, median intensity coverage of fragment peaks in MS/MS spectra increases from 58% by search engine annotation alone to 86%. The resulting annotation performance surpasses a human expert, especially on complex spectra such as those of larger phosphorylated peptides. Our system is also applicable to high resolution collision-induced dissociation data. It is available both as a part of MaxQuant and via a webserver that only requires an MS/MS spectrum and the corresponding peptides sequence, and which outputs publication quality, annotated MS/MS spectra (www.biochem.mpg.de/mann/tools/). It provides expert knowledge to beginners in the field of MS-based proteomics and helps advanced users to focus on unusual and possibly novel types of fragment ions.

  17. Fast MS/MS acquisition without dynamic exclusion enables precise and accurate quantification of proteome by MS/MS fragment intensity.

    Science.gov (United States)

    Zhang, Shen; Wu, Qi; Shan, Yichu; Zhao, Qun; Zhao, Baofeng; Weng, Yejing; Sui, Zhigang; Zhang, Lihua; Zhang, Yukui

    2016-05-20

    Most currently proteomic studies use data-dependent acquisition with dynamic exclusion to identify and quantify the peptides generated by the digestion of biological sample. Although dynamic exclusion permits more identifications and higher possibility to find low abundant proteins, stochastic and irreproducible precursor ion selection caused by dynamic exclusion limit the quantification capabilities, especially for MS/MS based quantification. This is because a peptide is usually triggered for fragmentation only once due to dynamic exclusion. Therefore the fragment ions used for quantification only reflect the peptide abundances at that given time point. Here, we propose a strategy of fast MS/MS acquisition without dynamic exclusion to enable precise and accurate quantification of proteome by MS/MS fragment intensity. The results showed comparable proteome identification efficiency compared to the traditional data-dependent acquisition with dynamic exclusion, better quantitative accuracy and reproducibility regardless of label-free based quantification or isobaric labeling based quantification. It provides us with new insights to fully explore the potential of modern mass spectrometers. This strategy was applied to the relative quantification of two human disease cell lines, showing great promises for quantitative proteomic applications.

  18. Ecological Epigenetics: Beyond MS-AFLP.

    Science.gov (United States)

    Schrey, Aaron W; Alvarez, Mariano; Foust, Christy M; Kilvitis, Holly J; Lee, Jacob D; Liebl, Andrea L; Martin, Lynn B; Richards, Christina L; Robertson, Marta

    2013-08-01

    Ecological Epigenetics studies the relationship between epigenetic variation and ecologically relevant phenotypic variation. As molecular epigenetic mechanisms often control gene expression, even across generations, they may impact many evolutionary processes. Multiple molecular epigenetic mechanisms exist, but methylation of DNA so far has dominated the Ecological Epigenetic literature. There are several molecular techniques used to screen methylation of DNA; here, we focus on the most common technique, methylation-sensitive-AFLP (MS-AFLP), which is used to identify genome-wide methylation patterns. We review studies that used MS-AFLP to address ecological questions, that describe which taxa have been investigated, and that identify general trends in the field. We then discuss, noting the general themes, four studies across taxa that demonstrate characteristics that increase the inferences that can be made from MS-AFLP data; we suggest that future MS-AFLP studies should incorporate these methods and techniques. We then review the short-comings of MS-AFLP and suggest alternative techniques that might address some of these limitations. Finally, we make specific suggestions for future research on MS-AFLP and identify questions that are most compelling and tractable in the short term.

  19. Validated HPLC-MS-MS method for determination of azithromycin in human plasma.

    Science.gov (United States)

    Barrett, B; Borek-Dohalský, V; Fejt, P; Vaingátová, S; Huclová, J; Nemec, B; Jelínek, I

    2005-09-01

    A validated, highly sensitive, and selective HPLC method with MS-MS detection has been developed for quantitative determination of azithromycin (AZI) in human Na2EDTA plasma. Roxithromycin (ROX) was used as internal standard. Human plasma containing AZI and internal standard was ultrafiltered through Centrifree Micropartition devices and the concentration of AZI was determined by isocratic HPLC-MS-MS. Multiple reaction monitoring mode (MRM) was used for MS-MS detection. The calibration plot was linear in the concentration range 2.55-551.43 ng mL(-1). Inter-day and Intra-day precision and accuracy of the proposed method were characterized by R.S.D and percentage deviation, respectively; both were less than 8%. Limit of quantification was 2.55 ng mL(-1). The proposed method was used to determine the pharmacokinetic profile of AZI (250-mg tablets).

  20. Application of LC-MS/MS for quantitative analysis of glucocorticoids and stimulants in biological fluids

    Institute of Scientific and Technical Information of China (English)

    Jamshed Haneef; Mohammad Shaharyar; Asif Husaina; Mohd Rashid; Ravinesh Mishra; Shama Parveen; Niyaz Ahmed; Manoj Pal; Deepak Kumar

    2013-01-01

    Liquid chromatography tandem mass chromatography (LC-MS/MS) is an important hyphenated technique for quantitative analysis of drugs in biological fluids. Because of high sensitivity and selectivity, LC-MS/MS has been used for pharmacokinetic studies, metabolites identification in the plasma and urine. This manuscript gives comprehensive analytical review, focusing on chromatographic separation approaches (column packing materials, column length and mobile phase) as well as different acquisition modes (SIM, MRM) for quantitative analysis of glucocorticoids and stimulants. This review is not meant to be exhaustive but rather to provide a general overview for detection and confirmation of target drugs using LC-MS/MS and thus useful in the doping analysis, toxicological studies as well as in pharmaceutical analysis.

  1. Nano LC-MS/MS: a robust setup for proteomic analysis.

    Science.gov (United States)

    Gaspari, Marco; Cuda, Giovanni

    2011-01-01

    Nanoscale liquid chromatography coupled to tandem mass spectrometry (nano LC-MS/MS) has become an essential tool in the field of proteomics. In fact, its sensitivity has advantages over conventional LC-MS/MS that allow the analysis of peptide mixtures in sample-limited situations (e.g., proteolytically digested proteins isolated by two-dimensional gel electrophoresis). Technical challenges, associated with low flow rates of the chromatographic separation, make this technology still difficult to run routinely. Here, we describe a nano LC-MS/MS setup that allows several weeks of continuous operation for the analysis of peptides derived by enzymatic digestion of either purified proteins or moderately complex protein mixtures.

  2. Isolation and characterization of a male fertility gene (Ms4) in soybean

    Science.gov (United States)

    Identifying a stable male-sterility system is crucial for the development of hybrid soybean. In soybean, eleven male-sterile, female-fertile mutants (ms1, ms2, ms3, ms4, ms5, ms6, ms7, ms8, ms9, msMOS, and msp) have been identified and some of which have been mapped to soybean chromosomes. The objec...

  3. Analysis of Carbamate Pesticides: Validation of Semi-Volatile Analysis by HPLC-MS/MS by EPA Method MS666

    Energy Technology Data Exchange (ETDEWEB)

    Owens, J; Koester, C

    2008-05-14

    The Environmental Protection Agency's (EPA) Region 5 Chicago Regional Laboratory (CRL) developed a method for analysis of aldicarb, bromadiolone, carbofuran, oxamyl, and methomyl in water by high performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS), titled Method EPA MS666. This draft standard operating procedure (SOP) was distributed to multiple EPA laboratories and to Lawrence Livermore National Laboratory, which was tasked to serve as a reference laboratory for EPA's Environmental Reference Laboratory Network (ERLN) and to develop and validate analytical procedures. The primary objective of this study was to validate and verify the analytical procedures described in MS666 for analysis of carbamate pesticides in aqueous samples. The gathered data from this validation study will be used to: (1) demonstrate analytical method performance; (2) generate quality control acceptance criteria; and (3) revise the SOP to provide a validated method that would be available for use during a homeland security event. The data contained in this report will be compiled, by EPA CRL, with data generated by other EPA Regional laboratories so that performance metrics of Method EPA MS666 can be determined.

  4. Outdoor and indoor benzene evaluation by GC-FID and GC-MS/MS

    OpenAIRE

    José A. Sousa; Domingues, Valentina F.; Rosas, Mónica S.; Ribeiro, Susana; Alvim-Ferraz, Maria da Conceição M.

    2011-01-01

    The evaluation of benzene in different environments such as indoor (with and without tobacco smoke), a city area, countryside, gas stations and near exhaust pipes from cars running on different types of fuels was performed. The samples were analyzed using gas chromatography (GC) with flame ionization detection (FID) and tandem mass spectrometric detection (MS/MS) (to confirm the identification of benzene in the air samples). Operating conditions for the GC-MS analysis were optimized ...

  5. A comparison of direct infusion MS and GC-MS for metabolic footprinting of yeast mutants

    DEFF Research Database (Denmark)

    Mass, S.; Villas-Bôas, Silas Granato; Hansen, Michael Adsetts Edberg;

    2007-01-01

    Recent technical advances in mass spectrometry (MS) have propelled this technology to the forefront of methods employed in metabolome analysis. Here, we compare two distinct analytical approaches based on MS for their potential in revealing specific metabolic footprints of yeast single-deletion m......Recent technical advances in mass spectrometry (MS) have propelled this technology to the forefront of methods employed in metabolome analysis. Here, we compare two distinct analytical approaches based on MS for their potential in revealing specific metabolic footprints of yeast single......-deletion mutants. Filtered fermentation broth samples were analyzed by GC-MS and direct infusion ESI-MS. The potential of both methods in producing specific and, therefore, discriminant metabolite profiles was evaluated using samples from several yeast deletion mutants grown in batch-culture conditions....... Thus, the GC-MS method is good for classification of mutants with altered nitrogen regulation as it primarily measures amino acids, whereas this method cannot classify mutants involved in regulation of phospholipids metabolism as well as the direct infusion MS (DI-MS) method. From the analysis, we find...

  6. Hearing Status Survey in Define MS Patients

    Directory of Open Access Journals (Sweden)

    Davood Rostamian

    2003-08-01

    Full Text Available Objective: This study was aimed to survey the hearing status of the patients with definite MS. The results of this study may help to confirm the diagnosis and to improve our knowledge of different aspects of this disease and to optimize the treatment and rehabilitative techniques. Material & Methods: This study is performed in audiology clinic of rehabilitation science faculty of Iran medical science university as an assesive-analytic procedure in winter of 2000 in 40 MS patients (Referred from the MS clinic of Shohada Hospital of 20 to 45 years old. All the patients have no history of otologic problems. The results of conventional audiologist tests (PTA, SRT, SDS, imittance audiometry and ABR findings of MS patients were compared to the results of control group. Results: The differences between the means of low, high and mid frequency PTAve in MS patients and control group were statistically significant (P<0.05. There was no significant difference between two groups in the speech test's results, statistically. The results of ART test show statistically significant differences between experimental and control groups. The only differences in ABR results were seen for the absolute latency of the wave V and IPLs (I-V, III-V between two groups. The amplitude ratio of V/I in MS patients 1.5 was within the normal range (0.5 to 2. There was a statistically significant relationship between mean of mid frequency PTAve and prolongation of absolute latency of the wave V. The relationship between ABR and SDS and also between ART and ABR were not statistically significant. Finally, the results of this study suggested that low, high and mid frequency PTAve, ART, absolute latency of the wave V, and IPLs III-V, I-V can be used ascomplementory method to confirm the diagnosis of MS with other conventional methods such as: MRI, CSF analysis, SEP and VEP.

  7. Metabolic profiling of roots of liquorice (Glycyrrhiza glabra) from different geographical areas by ESI/MS/MS and determination of major metabolites by LC-ESI/MS and LC-ESI/MS/MS.

    Science.gov (United States)

    Montoro, Paola; Maldini, Mariateresa; Russo, Mariateresa; Postorino, Santo; Piacente, Sonia; Pizza, Cosimo

    2011-02-20

    Liquid chromatography electrospray mass spectrometry (LC-ESI/MS) has been applied to the full characterization of saponins and phenolics in hydroalcoholic extracts of roots of liquorice (Glycyrrhiza glabra). Relative quantitative analyses of the samples with respect to the phenolic constituents and to a group of saponins related to glycyrrhizic acid were performed using LC-ESI/MS. For the saponin constituents, full scan LC-MS/MS fragmentation of the protonated (positive ion mode) or deprotonated (negative ion mode) molecular species generated diagnostic fragment ions that provided information concerning the triterpene skeleton and the number and nature of the substituents. On the basis of the specific fragmentation of glycyrrhizic acid, an LC-MS/MS method was developed in order to quantify the analyte in the liquorice root samples. Chinese G. glabra roots contained the highest levels of glycyrrhizic acid, followed by those from Italy (Calabria).

  8. Two Alternative Routes to MS2 Nanotubes

    Institute of Scientific and Technical Information of China (English)

    Yanqing LIU; Changsheng LI; Jinghai YANG; Zhong HUA; Junmao LI; Kehong YAN; Shuhuo ZHAO

    2007-01-01

    Inorganic tubular nanostructure MS2 (M=Mo, W, Nb, Ta) were synthesized by two alternative routes. Thermal decomposition method was used for producing fullerence-like MS2 (M=Mo, W) nanotubes on Al2O3 template using ammonium sulfur respectively; NbS2, and TaS2 nanotubes were obtained successfully by reducing corresponding metal trisulfide in a stream of H2 (mixed with N2 in some cases) at elevated temperatures.Detailed experimental procedure, and the characterization of associated results, were evaluated using X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and high resolution transmission electron microscopy (HRTEM). The result reveals that products are composed of high density of MS2 tubular nanostructures with the diameter of 100 nm and length of tens of micrometers. And no mistake, these 1-D (one-dimensional) tubular nanomaterials added quantities and varieties in the growing family of nanotubes of inorganic layered materials.

  9. Analysis of Hydrolysis Reaction of N-Phosphoryl Phenylalanine by HPLC-ESI-MS/MS

    Institute of Scientific and Technical Information of China (English)

    Shu Xia CAO; Jian Chen ZHANG; Jun XU; Xin Cheng LIAO; Yu Fen ZHAO

    2004-01-01

    Hydrolysis procedure of N-phosphoryl phenylalanine (DIPP-Phe) was studied by HPLC-ESI-MS/MS. The results showed that (HO)(i-PrO)P(O)Phe was the main intermediate and the hydrolysis of DIPP-Phe also occurred through a penta-coordinate transition state.

  10. Determination of anthelmintic drug residues in milk using UPLC-MS/MS with rapid polarity switching

    Science.gov (United States)

    A new UPLC-MS/MS (ultra-performance liquid chromatography coupled to tandem mass spectrometry) method was developed and validated to detect 38 anthelmintic drug residues, consisting of benzimidazoles, avermectins and flukicides. A modified QuEChERS-type extraction method was developed with an added...

  11. Analysis of biopharmaceutical proteins in biological matrices by LC-MS/MS I. Sample preparation

    NARCIS (Netherlands)

    Bischoff, Rainer; Bronsema, Kees J.; van de Merbel, Nico C.

    2013-01-01

    Part I of this review discusses sample-preparation aspects of quantifying biopharmaceutical proteins in complex biological matrices by LC-MS/MS with a focus on blood-derived body fluids. We conclude Part I with a short overview over options for automating the entire analytical procedure, which is

  12. The influence of the sample matrix on LC-MS/MS method development and analytical performance

    NARCIS (Netherlands)

    Koster, Remco Arjan

    2015-01-01

    In order to provide personalized patient treatment, a large number of analytical procedures is needed to measure a large variety of drugs in various human matrices. The analytical technique used for this research is Liquid Chromatography coupled with triple quadrupole mass spectrometry (LC-MS/MS). E

  13. Analysis of biopharmaceutical proteins in biological matrices by LC-MS/MS I. Sample preparation

    NARCIS (Netherlands)

    Bischoff, Rainer; Bronsema, Kees J.; van de Merbel, Nico C.

    2013-01-01

    Part I of this review discusses sample-preparation aspects of quantifying biopharmaceutical proteins in complex biological matrices by LC-MS/MS with a focus on blood-derived body fluids. We conclude Part I with a short overview over options for automating the entire analytical procedure, which is in

  14. STS-47 MS Davis and MS Jemison with LBNP device in SLJ module aboard OV-105

    Science.gov (United States)

    1992-01-01

    STS-47 Mission Specialist (MS) N. Jan Davis (left) and MS Mae C. Jemison prepare the lower body negative pressure (LBNP) device for the LBNP experiment in the Spacelab Japan (SLJ) science module aboard the Earth-orbiting Endeavour, Orbiter Vehicle (OV) 105. Displayed on the aft end cone in the background is an Auburn University banner.

  15. Dried blood spot analysis of creatinine with LC-MS/MS in addition to immunosuppressants analysis

    NARCIS (Netherlands)

    Koster, Remco A.; Greijdanus, Ben; Alffenaar, Jan-Willem C.; Touw, Daan J.

    2015-01-01

    In order to monitor creatinine levels or to adjust the dosage of renally excreted or nephrotoxic drugs, the analysis of creatinine in dried blood spots (DBS) could be a useful addition to DBS analysis. We developed a LC-MS/MS method for the analysis of creatinine in the same DBS extract that was use

  16. Gluten Detection and Speciation by Liquid Chromatography Mass Spectrometry (LC-MS/MS

    Directory of Open Access Journals (Sweden)

    Stephen Lock

    2013-12-01

    Full Text Available Liquid chromatography tandem mass spectrometry (LC-MS/MS has been used historically in proteomics research for over 20 years. However, until recently LC-MS/MS has only been routinely used in food testing for small molecule contaminant detection, for example pesticide and veterinary residue detection, and not as a replacement of microbiological food testing methods, specifically allergen analysis. Over the last couple of years, articles have started to be published which describe the detection of allergens by LC-MS/MS. In this article we will describe how LC-MS/MS can be applied in the area of gluten detection and how it can be used to specifically differentiate the species of gluten used in food, where specific markers for each variety of gluten can be simultaneously acquired and detected at the same time. The article will discuss the effect of variety on the peptide response observed from different wheat grain varieties and will describe the sample preparation protocol which is essential for generating the peptide markers used for speciation.

  17. Analytical Method Details (MS): SE8_MS3 [Metabolonote[Archive

    Lifescience Database Archive (English)

    Full Text Available SE8_MS3 LC-FT-ICR-MS ESI positive method 3 Agilent1100 HPLC (Agilent), LTQ-FT (Ther...e solved in 300uL 80% methanol solution. 20uL sample is injected into HPLC after 0.2um membrane filter treatment. HPLC

  18. Analytical Method Details (MS): SE4_MS4 [Metabolonote[Archive

    Lifescience Database Archive (English)

    Full Text Available SE4_MS4 LC-FT-ICR-MS ESI positive method 4 Agilent1100 HPLC (Agilent), LTQ-FT (Ther... (Waters). 20uL sample is injected into HPLC after 0.2um membrane filter treatment. HPLC conditions: Agile...nt 1100 series (Agilent), Column: TSKgel-100V (4.6 x 250 mm, 5 micrometer; TOSOH),

  19. Analytical Method Details (MS): SE8_MS4 [Metabolonote[Archive

    Lifescience Database Archive (English)

    Full Text Available SE8_MS4 LC-FT-ICR-MS ESI positive method 4 Agilent1100 HPLC (Agilent), LTQ-FT (Ther...e solved in 300uL 80% methanol solution. 20uL sample is injected into HPLC after 0.2um membrane filter treatment. HPLC

  20. Analytical Method Details (MS): SE2_MS2 [Metabolonote[Archive

    Lifescience Database Archive (English)

    Full Text Available SE2_MS2 LC-FT-ICR-MS ESI positive method 2 Agilent1100 HPLC (Agilent), LTQ-FT (Ther...(100mg) are solved in 300uL 80% methanol solution. 20uL sample is injected into HPLC after 0.2um membrane filter treatment. HPLC

  1. Analytical Method Details (MS): SE41_MS1 [Metabolonote[Archive

    Lifescience Database Archive (English)

    Full Text Available SE41_MS1 LC-Orbitrap-MS ESI positive method Agilent1100 HPLC (Agilent), LTQ-Orbitra...ng powder (100mg) are solved in 300uL 80% methanol solution. 5uL sample is injected into HPLC after 0.2um me...mbrane filter treatment. HPLC conditions: Agilent 1200 series (Agilent), Column:

  2. Analytical Method Details (MS): SE5_MS1 [Metabolonote[Archive

    Lifescience Database Archive (English)

    Full Text Available SE5_MS1 LC-FT-ICR-MS ESI positive method 1 Agilent1100 HPLC (Agilent), LTQ-FT (Ther...(100mg) are solved in 300uL methanol solution. 20uL sample is injected into HPLC after 0.2um membrane filter treatment. HPLC

  3. Analytical Method Details (MS): SE32_MS1 [Metabolonote[Archive

    Lifescience Database Archive (English)

    Full Text Available SE32_MS1 LC-FT-ICR-MS ESI positive method 1 Agilent1100 HPLC (Agilent), LTQ-FT (The... (100mg) are solved in 300uL 80% methanol solution. 20uL sample is injected into HPLC after 0.2um membrane filter treatment. HPLC

  4. Analytical Method Details (MS): SE14_MS1 [Metabolonote[Archive

    Lifescience Database Archive (English)

    Full Text Available SE14_MS1 LC-FT-ICR-MS ESI positive method 1 Agilent1100 HPLC (Agilent), LTQ-FT (The... (100mg) are solved in 300uL 80% methanol solution. 20uL sample is injected into HPLC after 0.2um membrane filter treatment. HPLC

  5. Analytical Method Details (MS): SE16_MS1 [Metabolonote[Archive

    Lifescience Database Archive (English)

    Full Text Available SE16_MS1 LC-FT-ICR-MS ESI positive method 1 Agilent1100 HPLC (Agilent), LTQ-FT (The... (100mg) are solved in 300uL 80% methanol solution. 20uL sample is injected into HPLC after 0.2um membrane filter treatment. HPLC

  6. Analytical Method Details (MS): SE26_MS1 [Metabolonote[Archive

    Lifescience Database Archive (English)

    Full Text Available SE26_MS1 LC-FT-ICR-MS ESI positive method 1 Agilent1100 HPLC (Agilent), LTQ-FT (The... (100mg) are solved in 300uL 80% methanol solution. 20uL sample is injected into HPLC after 0.2um membrane filter treatment. HPLC

  7. Analytical Method Details (MS): SE8_MS1 [Metabolonote[Archive

    Lifescience Database Archive (English)

    Full Text Available SE8_MS1 LC-FT-ICR-MS ESI positive method 1 Agilent1100 HPLC (Agilent), LTQ-FT (Ther...e solved in 300uL 80% methanol solution. 20uL sample is injected into HPLC after 0.2um membrane filter treatment. HPLC

  8. Analytical Method Details (MS): SE10_MS1 [Metabolonote[Archive

    Lifescience Database Archive (English)

    Full Text Available SE10_MS1 LC-FT-ICR-MS ESI positive method 1 Agilent1100 HPLC (Agilent), LTQ-FT (The... (100mg) are solved in 300uL 80% methanol solution. 20uL sample is injected into HPLC after 0.2um membrane filter treatment. HPLC

  9. Analytical Method Details (MS): SE12_MS1 [Metabolonote[Archive

    Lifescience Database Archive (English)

    Full Text Available SE12_MS1 LC-FT-ICR-MS ESI positive method 1 Agilent1100 HPLC (Agilent), LTQ-FT (The... (100mg) are solved in 300uL 80% methanol solution. 20uL sample is injected into HPLC after 0.2um membrane filter treatment. HPLC

  10. Analytical Method Details (MS): SE9_MS2 [Metabolonote[Archive

    Lifescience Database Archive (English)

    Full Text Available SE9_MS2 LC-FT-ICR-MS ESI positive method 2 Agilent1100 HPLC (Agilent), LTQ-FT (Ther...and centrifuged (15000rpm, 10min, 4 degree C). 20uL sample is injected into HPLC ...after 0.2um membrane filter treatment. HPLC conditions: Agilent 1100 series (Agilent), Column: TSKgel-100V (

  11. Analytical Method Details (MS): SE34_MS1 [Metabolonote[Archive

    Lifescience Database Archive (English)

    Full Text Available SE34_MS1 LC-FT-ICR-MS ESI positive method 1 Agilent1100 HPLC (Agilent), LTQ-FT (The... (100mg) are solved in 300uL 80% methanol solution. 20uL sample is injected into HPLC after 0.2um membrane filter treatment. HPLC

  12. Analytical Method Details (MS): SE9_MS1 [Metabolonote[Archive

    Lifescience Database Archive (English)

    Full Text Available SE9_MS1 LC-FT-ICR-MS ESI positive method 1 Agilent1100 HPLC (Agilent), LTQ-FT (Ther...and centrifuged (15000rpm, 10min, 4 degree C). 20uL sample is injected into HPLC ...after 0.2um membrane filter treatment. HPLC conditions: Agilent 1100 series (Agilent), Column: TSKgel-100V (

  13. Analytical Method Details (MS): SE29_MS1 [Metabolonote[Archive

    Lifescience Database Archive (English)

    Full Text Available SE29_MS1 LC-FT-ICR-MS ESI positive method 1 Agilent1100 HPLC (Agilent), LTQ-FT (The... (100mg) are solved in 300uL 80% methanol solution. 20uL sample is injected into HPLC after 0.2um membrane filter treatment. HPLC

  14. Analytical Method Details (MS): SE4_MS1 [Metabolonote[Archive

    Lifescience Database Archive (English)

    Full Text Available SE4_MS1 LC-FT-ICR-MS ESI positive method 1 Agilent1100 HPLC (Agilent), LTQ-FT (Ther...(100mg) are solved in 300uL methanol solution. 20uL sample is injected into HPLC after 0.2um membrane filter treatment. HPLC

  15. Analytical Method Details (MS): SE25_MS1 [Metabolonote[Archive

    Lifescience Database Archive (English)

    Full Text Available SE25_MS1 LC-FT-ICR-MS ESI positive method 1 Agilent1100 HPLC (Agilent), LTQ-FT (The... (100mg) are solved in 300uL 80% methanol solution. 20uL sample is injected into HPLC after 0.2um membrane filter treatment. HPLC

  16. Analytical Method Details (MS): SE3_MS1 [Metabolonote[Archive

    Lifescience Database Archive (English)

    Full Text Available SE3_MS1 LC-FT-ICR-MS ESI positive method 1 Agilent1100 HPLC (Agilent), LTQ-FT (Ther...(100mg) are solved in 300uL 80% methanol solution. 20uL sample is injected into HPLC after 0.2um membrane filter treatment. HPLC

  17. Analytical Method Details (MS): SE40_MS1 [Metabolonote[Archive

    Lifescience Database Archive (English)

    Full Text Available SE40_MS1 LC-Orbitrap-MS ESI positive method 1 Agilent1100 HPLC (Agilent), LTQ-Orbit...ting powder (100mg) are solved in 300uL 80% methanol solution. 5uL sample is injected into HPLC after 0.2um ...membrane filter treatment. HPLC conditions: Agilent 1200 series (Agilent), Column

  18. Analytical Method Details (MS): SE7_MS1 [Metabolonote[Archive

    Lifescience Database Archive (English)

    Full Text Available SE7_MS1 LC-Orbitrap-MS ESI positive method 1 Agilent1100 HPLC (Agilent), LTQ-Orbitr... and centrifuged (15000rpm, 10min, 4 degree C). 20uL of the supernatant (300uL) is injected into HPLC... after 0.2um membrane filter treatment. HPLC conditions: Agilent 1100 series (Agilent),

  19. Analytical Method Details (MS): SE36_MS1 [Metabolonote[Archive

    Lifescience Database Archive (English)

    Full Text Available SE36_MS1 LC-FT-ICR-MS ESI positive method 1 Agilent1100 HPLC (Agilent), LTQ-FT (The... (100mg) are solved in 300uL 80% methanol solution. 20uL sample is injected into HPLC after 0.2um membrane filter treatment. HPLC

  20. Analytical Method Details (MS): SE2_MS3 [Metabolonote[Archive

    Lifescience Database Archive (English)

    Full Text Available SE2_MS3 LC-FT-ICR-MS ESI positive method 3 Agilent1100 HPLC (Agilent), LTQ-FT (Ther...(100mg) are solved in 300uL 80% methanol solution. 20uL sample is injected into HPLC after 0.2um membrane filter treatment. HPLC

  1. Analytical Method Details (MS): SE4_MS2 [Metabolonote[Archive

    Lifescience Database Archive (English)

    Full Text Available SE4_MS2 LC-FT-ICR-MS ESI positive method 2 Agilent1100 HPLC (Agilent), LTQ-FT (Ther...ethanol solution. 20uL sample is injected into HPLC after 0.2um membrane filter treatment. HPLC

  2. Analytical Method Details (MS): SE8_MS2 [Metabolonote[Archive

    Lifescience Database Archive (English)

    Full Text Available SE8_MS2 LC-FT-ICR-MS ESI positive method 2 Agilent1100 HPLC (Agilent), LTQ-FT (Ther...e solved in 300uL 80% methanol solution. 20uL sample is injected into HPLC after 0.2um membrane filter treatment. HPLC

  3. Analytical Method Details (MS): SE11_MS1 [Metabolonote[Archive

    Lifescience Database Archive (English)

    Full Text Available SE11_MS1 LC-FT-ICR-MS ESI positive method 1 Agilent1100 HPLC (Agilent), LTQ-FT (The... (100mg) are solved in 300uL 80% methanol solution. 20uL sample is injected into HPLC after 0.2um membrane filter treatment. HPLC

  4. Analytical Method Details (MS): SE6_MS1 [Metabolonote[Archive

    Lifescience Database Archive (English)

    Full Text Available SE6_MS1 LC-Orbitrap-MS ESI positive method 1 Agilent1100 HPLC (Agilent), LTQ-Orbitr... and centrifuged (15000rpm, 10min, 4 degree C). 20uL of the supernatant (300uL) is injected into HPLC... after 0.2um membrane filter treatment. HPLC conditions: Agilent 1100 series (Agilent),

  5. Analytical Method Details (MS): SE2_MS1 [Metabolonote[Archive

    Lifescience Database Archive (English)

    Full Text Available SE2_MS1 LC-FT-ICR-MS ESI positive method 1 Agilent1100 HPLC (Agilent), LTQ-FT (Ther...(100mg) are solved in 300uL 80% methanol solution. 20uL sample is injected into HPLC after 0.2um membrane filter treatment. HPLC

  6. Analytical Method Details (MS): SE27_MS1 [Metabolonote[Archive

    Lifescience Database Archive (English)

    Full Text Available SE27_MS1 LC-FT-ICR-MS ESI positive method 1 Agilent1100 HPLC (Agilent), LTQ-FT (The... (100mg) are solved in 300uL 80% methanol solution. 20uL sample is injected into HPLC after 0.2um membrane filter treatment. HPLC

  7. Analytical Method Details (MS): SE40_MS2 [Metabolonote[Archive

    Lifescience Database Archive (English)

    Full Text Available SE40_MS2 LC-Orbitrap-MS ESI positive method 2 Nexera HPLC (Shimadzu), LTQ-Orbitrap ... resulting powder (100mg) are solved in 300uL 80% methanol solution. 5uL sample is injected into HPLC after ...0.2um membrane filter treatment. HPLC conditions: Shimadzu Nexera (Shimadzu), Col

  8. Analytical Method Details (MS): SE17_MS1 [Metabolonote[Archive

    Lifescience Database Archive (English)

    Full Text Available SE17_MS1 LC-FT-ICR-MS ESI positive method 1 Agilent1100 HPLC (Agilent), LTQ-FT (The... (100mg) are solved in 300uL 80% methanol solution. 20uL sample is injected into HPLC after 0.2um membrane filter treatment. HPLC

  9. Analytical Method Details (MS): SE1_MS1 [Metabolonote[Archive

    Lifescience Database Archive (English)

    Full Text Available SE1_MS1 LC-FT-ICR-MS ESI positive method 1 Agilent1100 HPLC (Agilent), LTQ-FT (Ther...(100mg) are solved in 300uL 80% methanol solution. 20uL sample is injected into HPLC after 0.2um membrane filter treatment. HPLC

  10. Analytical Method Details (MS): SE20_MS1 [Metabolonote[Archive

    Lifescience Database Archive (English)

    Full Text Available SE20_MS1 LC-FT-ICR-MS ESI positive method 1 Agilent1100 HPLC (Agilent), LTQ-FT (The... (100mg) are solved in 300uL 80% methanol solution. 20uL sample is injected into HPLC after 0.2um membrane filter treatment. HPLC

  11. Analytical Method Details (MS): SE33_MS1 [Metabolonote[Archive

    Lifescience Database Archive (English)

    Full Text Available SE33_MS1 LC-FT-ICR-MS ESI positive method 1 Agilent1100 HPLC (Agilent), LTQ-FT (The... (100mg) are solved in 300uL 80% methanol solution. 20uL sample is injected into HPLC after 0.2um membrane filter treatment. HPLC

  12. Analytical Method Details (MS): SE13_MS1 [Metabolonote[Archive

    Lifescience Database Archive (English)

    Full Text Available SE13_MS1 LC-FT-ICR-MS ESI positive method 1 Agilent1100 HPLC (Agilent), LTQ-FT (The... (100mg) are solved in 300uL 80% methanol solution. 20uL sample is injected into HPLC after 0.2um membrane filter treatment. HPLC

  13. Analytical Method Details (MS): SE35_MS1 [Metabolonote[Archive

    Lifescience Database Archive (English)

    Full Text Available SE35_MS1 LC-FT-ICR-MS ESI positive method 1 Agilent1100 HPLC (Agilent), LTQ-FT (The... (100mg) are solved in 300uL 80% methanol solution. 20uL sample is injected into HPLC after 0.2um membrane filter treatment. HPLC

  14. High sensitive and throughput screening of Aflatoxin using MALDI-TOF-TOF-PSD-MS/MS

    Science.gov (United States)

    We have achieved sensitive and efficient detection of aflatoxin B1(AFB1) through matrix-assisted laser desorption/ionization time-of-flight-time-of-flight mass spectrometry (MALDI-TOF-TOF) and post-source decay (PSD) tandem mass spectrometry (MS/MS) using an acetic acid – a-cyano-4-hydroxycinnamic a...

  15. Multiple structure alignment with msTALI

    Directory of Open Access Journals (Sweden)

    Shealy Paul

    2012-05-01

    Full Text Available Abstract Background Multiple structure alignments have received increasing attention in recent years as an alternative to multiple sequence alignments. Although multiple structure alignment algorithms can potentially be applied to a number of problems, they have primarily been used for protein core identification. A method that is capable of solving a variety of problems using structure comparison is still absent. Here we introduce a program msTALI for aligning multiple protein structures. Our algorithm uses several informative features to guide its alignments: torsion angles, backbone Cα atom positions, secondary structure, residue type, surface accessibility, and properties of nearby atoms. The algorithm allows the user to weight the types of information used to generate the alignment, which expands its utility to a wide variety of problems. Results msTALI exhibits competitive results on 824 families from the Homstrad and SABmark databases when compared to Matt and Mustang. We also demonstrate success at building a database of protein cores using 341 randomly selected CATH domains and highlight the contribution of msTALI compared to the CATH classifications. Finally, we present an example applying msTALI to the problem of detecting hinges in a protein undergoing rigid-body motion. Conclusions msTALI is an effective algorithm for multiple structure alignment. In addition to its performance on standard comparison databases, it utilizes clear, informative features, allowing further customization for domain-specific applications. The C++ source code for msTALI is available for Linux on the web at http://ifestos.cse.sc.edu/mstali.

  16. An impulse-driven liquid-droplet deposition interface for combining LC with MALDI MS and MS/MS.

    Science.gov (United States)

    Young, J Bryce; Li, Liang

    2006-03-01

    A simple and robust impulse-driven droplet deposition system was developed for off-line liquid chromatography matrix-assisted laser desorption ionization mass spectrometry (LC-MALDI MS). The system uses a solenoid operated with a pulsed voltage power supply to generate impulses that dislodge the hanging droplets from the LC outlet directly to a MALDI plate via a momentum transfer process. There is no contact between the LC outlet and the collection surface. The system is compatible with solvents of varying polarity and viscosity, and accommodates the use of hydrophobic and hydrophilic MALDI matrices. MALDI spots are produced on-line with the separation, and do not require further processing before MS analysis. It is shown that high quality MALDI spectra from 5 fmol of pyro-Glu-fibrinopeptide deposition after LC separation could be obtained using the device, indicating that there was no sample loss in the interface. To demonstrate the analytical performance of the system as a proteome analysis tool, a range of BSA digest concentrations covering about 3 orders of magnitude, from 5 fmol to 1 pmol, were analyzed by LC-MALDI quadrupole time-of-flight MS, yielding 6 and 57% amino acid sequence coverage, respectively. In addition, a complex protein mixture of an E. coli cell extract was tryptically digested and analyzed by LC-MALDI MS, resulting in the detection of a total of 409 unique peptides from 100 fractions of 15-s intervals.

  17. The concept of spectral accuracy for MS.

    Science.gov (United States)

    Wang, Yongdong; Gu, Ming

    2010-09-01

    Though MS has always appeared to be quite different from spectroscopy to analytical chemists who are familiar with both, a careful examination from historical and theoretical perspectives reveals a striking similarity between the two. With the introduction of spectral accuracy, a companion concept to the better known mass accuracy, new capabilities previously thought unfeasible can now be enabled for MS. (To listen to a podcast about this article, please go to the Analytical Chemistry multimedia page at pubs.acs.org/page/ancham/audio/index.html .).

  18. e-FILTERS OF MS-ALGEBRAS

    Institute of Scientific and Technical Information of China (English)

    M.Sambasiva RAO

    2013-01-01

    The notion of e-filters is introduced in an MS-algebra and characterized.The concept of D-filters is introduced and a set of equivalent conditions under which every D-filter is an e-filter are given.The properties of the space of all prime e-filters of an MS-algebra are observed.The concept of D-prime filters is introduced and then a set of equivalent conditions are derived for a prime e-filter to become a D-prime filter in topological terms.

  19. LC-MS-MS Method for Analysis of Opiates in Wastewater During Football Games II.

    Science.gov (United States)

    Gul, Waseem; Stamper, Brandon; Godfrey, Murrell; Gul, Shahbaz W; ElSohly, Mahmoud A

    2016-06-01

    Continuing our previous studies analyzing drugs of abuse in municipal wastewater, a method was developed for the analysis of opiates in wastewater samples using liquid chromatography coupled with tandem mass spectrometry (LC-MS-MS). Eight opiate drugs and metabolites were analyzed including codeine, hydrocodone, hydromorphone, 6-monoacetylmorphine (6-MAM, the primary urinary metabolite of heroin), morphine, norhydrocodone (the primary urinary metabolite of hydrocodone), oxycodone and oxymorphone. These drugs were chosen because of their widespread abuse. Wastewater samples were collected at both the Oxford Waste Water Treatment Plant in Oxford, Mississippi (MS) and the University Wastewater Treatment Plant in University, MS. These wastewater samples were collected on weekends in which the Ole Miss Rebel football team held home games (Vaught-Hemingway Stadium, University, MS 38677). The collected samples were analyzed using a validated method and found to contain codeine, hydrocodone, hydromorphone, morphine, norhydrocodone, oxycodone and oxymorphone. None of the samples contained 6-MAM.

  20. MS/MS similarity networking accelerated target profiling of triterpene saponins in Eleutherococcus senticosus leaves.

    Science.gov (United States)

    Ge, Yue-Wei; Zhu, Shu; Yoshimatsu, Kayo; Komatsu, Katsuko

    2017-07-15

    The targeted mass information of compounds accelerated their discovery in a large volume of untargeted MS data. An MS/MS similarity networking is advanced in clustering the structural analogues, which benefits the collection of mass information of similar compounds. The triterpene saponins extracted from Eleutherococcus senticosus leaves (ESL), a kind of functional tea, have shown promise in the relief of Alzheimer's disease. In this work, a target-precursor list (TPL) generated using MS/MS similarity networking was employed to rapidly trace 106 triterpene saponins from the aqueous extracts of ESL, of which 49 were tentatively identified as potentially new triterpene saponins. Moreover, a compound database of triterpene saponins was established and successfully applied to uncover their distribution features in ESL samples collected from different areas. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Metabolomics and Trace Element Analysis of Camel Tear by GC-MS and ICP-MS.

    Science.gov (United States)

    Ahamad, Syed Rizwan; Raish, Mohammad; Yaqoob, Syed Hilal; Khan, Altaf; Shakeel, Faiyaz

    2017-06-01

    Camel tear metabolomics and elemental analysis are useful in getting the information regarding the components responsible for maintaining the protective system that allows living in the desert and dry regions. The aim of this study was to correlate that the camel tears can be used as artificial tears for the evaluation of dryness in the eye. Eye biomarkers of camel tears were analyzed by gas chromatography-mass spectroscopy (GC-MS) and inductively coupled plasma mass spectroscopy (ICP-MS). The major compounds detected in camel tears by GC-MS were alanine, valine, leucine, norvaline, glycine, cadaverine, urea, ribitol, sugars, and higher fatty acids like octadecanoic acid and hexadecanoic acid. GC-MS analysis of camel tears also finds several products of metabolites and its associated metabolic participants. ICP-MS analysis showed the presence of different concentration of elemental composition in the camel tears.

  2. Instrument-independent software tools for the analysis of MS-MS and LC-MS lipidomics data.

    Science.gov (United States)

    Haimi, Perttu; Chaithanya, Krishna; Kainu, Ville; Hermansson, Martin; Somerharju, Pentti

    2009-01-01

    Mass spectrometry (MS), particularly electrospray-MS, is the key tool in modern lipidomics. However, as even a modest scale experiment produces a great amount of data, data processing often becomes limiting. Notably, the software provided with MS instruments are not well suited for quantitative analysis of lipidomes because of the great variety of species present and complexities in response calibration. Here we describe the use of two recently introduced software tools: lipid mass spectrum analysis (LIMSA) and spectrum extraction from chromatographic data (SECD), which significantly increase the speed and reliability of mass spectrometric analysis of complex lipidomes. LIMSA is a Microsoft Excel add-on that (1) finds and integrates the peaks in an imported spectrum, (2) identifies the peaks, (3) corrects the peak areas for overlap by isotopic peaks of other species and (4) quantifies the identified species using included internal standards. LIMSA is instrument-independent because it processes text-format MS spectra. Typically, the analysis of one spectrum takes only a few seconds.The SECD software allows one to display MS chromatograms as two-dimensional maps, which is useful for visual inspection of the data. More importantly, however, SECD allows one to extract mass spectra from user-defined regions of the map for further analysis with, e.g., LIMSA. The use of select regions rather than simple time-range averaging significantly improves the signal-to-noise ratio as signals outside the region of interest are more efficiently excluded. LIMSA and SECD have proven to be robust and convenient tools and are available free of charge from the authors.

  3. Dopamine, T cells and multiple sclerosis (MS).

    Science.gov (United States)

    Levite, Mia; Marino, Franca; Cosentino, Marco

    2017-03-10

    Dopamine is a key neurotransmitter that induces critical effects in the nervous system and in many peripheral organs, via 5 dopamine receptors (DRs): D1R-D5R. Dopamine also induces many direct and very potent effects on many DR-expressing immune cells, primarily T cells and dendritic cells. In this review, we focus only on dopamine receptors, effects and production in T cells. Dopamine by itself (at an optimal concentration of~0.1 nM) induces multiple function of resting normal human T cells, among them: T cell adhesion, chemotactic migration, homing, cytokine secretion and others. Interestingly, dopamine activates resting effector T cells (Teffs), but suppresses regulatory T cells (Tregs), and both effects lead eventually to Teff activation. Dopamine-induced effects on T cells are dynamic, context-sensitive and determined by the: T cell activation state, T cell type, DR type, and dopamine concentration. Dopamine itself, and also few dopaminergic molecules/ drugs that are in clinical use for cardiac, neurological and other non-immune indications, have direct effects on human T cells (summarized in this review). These dopaminergic drugs include: dopamine = intropin, L-DOPA, bromocriptine, pramipexole, pergolide, haloperidol, pimozide, and amantadine. Other dopaminergic drugs were not yet tested for their direct effects on T cells. Extensive evidence in multiple sclerosis (MS) and experimental autoimmune encephalomyelitis (EAE) show dopaminergic dysregulations in T cells in these diseases: D1-like DRs are decreased in Teffs of MS patients, and dopamine does not affect these cells. In contrast, D1-like DRs are increased in Tregs of MS patients, possibly causing functional Treg impairment in MS. Treatment of MS patients with interferon β (IFN-β) increases D1-like DRs and decreases D2-like DRs in Teffs, decreases D1-like DRs in Tregs, and most important: restores responsiveness of patient's Teffs to dopamine. DR agonists and antagonists confer some benefits in

  4. Improving protein identification sensitivity by combining MS and MS/MS information for shotgun proteomics using LTQ-Orbitrap high mass accuracy data.

    Science.gov (United States)

    Lu, Bingwen; Motoyama, Akira; Ruse, Cristian; Venable, John; Yates, John R

    2008-03-15

    We investigated and compared three approaches for shotgun protein identification by combining MS and MS/MS information using LTQ-Orbitrap high mass accuracy data. In the first approach, we employed a unique mass identifier method where MS peaks matched to peptides predicted from proteins identified from an MS/MS database search are first subtracted before using the MS peaks as unique mass identifiers for protein identification. In the second method, we used an accurate mass and time tag method by building a potential mass and retention time database from previous MudPIT analyses. For the third method, we used a peptide mass fingerprinting-like approach in combination with a randomized database for protein identification. We show that we can improve protein identification sensitivity for low-abundance proteins by combining MS and MS/MS information. Furthermore, "one-hit wonders" from MS/MS database searching can be further substantiated by MS information and the approach improves the identification of low-abundance proteins. The advantages and disadvantages for the three approaches are then discussed.

  5. Ms. Affirmation and Her Technicolor Responses.

    Science.gov (United States)

    Johnson-Kuby, Sue Ann; Katz, Claudia Anne

    1997-01-01

    Presents four questions from teachers regarding "classroom dilemmas" (such as seating assignments, requests for bathroom visits, and parent/teacher communication) with the responses by "Ms. Affirmation," a middle-school guidance counselor who collaborates with teachers to assist them in working with students. (SR)

  6. 78 FR 25336 - Mississippi Disaster # MS-00066

    Science.gov (United States)

    2013-04-30

    ... From the Federal Register Online via the Government Publishing Office SMALL BUSINESS ADMINISTRATION Mississippi Disaster MS-00066 AGENCY: U.S. Small Business Administration. ACTION: Notice. SUMMARY... Application Deadline Date: 01/21/2014. ADDRESSES: Submit completed loan applications to: U.S. Small...

  7. 77 FR 58900 - Mississippi Disaster #MS-00060

    Science.gov (United States)

    2012-09-24

    ... ADMINISTRATION Mississippi Disaster MS-00060 AGENCY: U.S. Small Business Administration. ACTION: Notice. SUMMARY... completed loan applications to: U.S. Small Business Administration, Processing and Disbursement Center... Disaster Assistance, U.S. Small Business Administration, 409 3rd Street SW., Suite 6050, Washington,...

  8. 2013 NRCS-USGS Lidar: Lauderdale (MS)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TASK NAME:NRCS LAUDERDALE MS 0.7M NPS LIDAR. LiDAR Data Acquisition and Processing Production Task. USGS Contract No. G10PC00057. Task Order No. G12PD000125 Woolpert...

  9. Consistentie met MS-DOS software

    NARCIS (Netherlands)

    Olsthoorn TN

    1988-01-01

    Zonder de keuze van een zekere standaard-lijn ten aanzien van de software die men zelf gebruikt, kan nauwelijks efficient met een computer worden gewerkt. Onder UNIX en op de Macintosh is het gebruik van programma's en de uitwisseling van gegevens daartussen gestandaardiseerd. Onder MS-DOS

  10. Global MS-Based Proteomics Drug Profiling.

    Science.gov (United States)

    Carvalho, Ana Sofia; Matthiesen, Rune

    2016-01-01

    DNA-based technologies such as RNAi, chemical-genetic profiling, or gene expression profiling by DNA microarrays combined with other biochemical methods are established strategies for surveying drug mechanisms. Such approaches can provide mechanistic information on how drugs act and affect cellular pathways. By studying how cancer cells compensate for the drug treatment, novel targets used in a combined treatment can be designed. Furthermore, toxicity effects on cells not targeted can be obtained on a molecular level. For example, drug companies are particularly interested in studying the molecular side effects of drugs in the liver. In addition, experiments with the purpose of elucidating liver toxicity can be studied using samples obtained from animal models exposed to different concentrations of a drug over time. More recently considerable advances in mass spectrometry (MS) technologies and bioinformatics tools allows informative global drug profiling experiments to be performed at a cost comparable to other large-scale technologies such as DNA-based technologies. Moreover, MS-based proteomics provides an additional layer of information on the dynamic regulation of proteins translation and particularly protein degradation. MS-based proteomics approaches combined with other biochemical methods delivers information on regulatory networks, signaling cascades, and metabolic pathways upon drug treatment. Furthermore, MS-based proteomics can provide additional information on single amino acid polymorphisms, protein isoform distribution, posttranslational modifications, and subcellular localization. In this chapter, we will share our experience using MS based proteomics as a pharmacoproteomics strategy to characterize drug mechanisms of action in single drug therapy or in multidrug combination. Finally, the emergence of integrated proteogenomics analysis, such as "The Cancer Genome Atlas" program, opened interesting perspectives to extend this approach to drug target

  11. Retinoid quantification by HPLC/MS(n)

    Science.gov (United States)

    McCaffery, Peter; Evans, James; Koul, Omanand; Volpert, Amy; Reid, Kevin; Ullman, M. David

    2002-01-01

    Retinoic acid (RA) mediates most of the biological effects of vitamin A that are essential for vertebrate survival. It acts through binding to receptors that belong to the nuclear receptor transcription factor superfamily (Mangelsdorf et al. 1994). It is also a highly potent vertebrate teratogen. To determine the function and effects of endogenous and exogenous RA, it is important to have a highly specific, sensitive, accurate, and precise analytical procedure. Current analyses of RA and other retinoids are labor intensive, of poor sensitivity, have limited specificity, or require compatibility with RA reporter cell lines (Chen et al. 1995. BIOCHEM: Pharmacol. 50: 1257-1264; Creech Kraft et al. 1994. BIOCHEM: J. 301: 111-119; Lanvers et al. 1996. J. Chromatogr. B Biomed. Appl. 685: 233-240; Maden et al. 1998. DEVELOPMENT: 125: 4133-4144; Wagner et al. 1992. DEVELOPMENT: 116: 55-66). This paper describes an HPLC/mass spectrometry/mass spectrometry product ion scan (HPLC/MS(n)) procedure for the analysis of retinoids that employs atmospheric pressure chemical ionization MS. The retinoids are separated by normal-phase column chromatography with a linear hexane-isopropanol-dioxane gradient. Each retinoid is detected by a unique series of MS(n) functions set at optimal collision-induced dissociation energy (30% to 32%) for all MS(n) steps. The scan events are divided into three segments, based on HPLC elution order, to maximize the mass spectrometer duty cycle. The all-trans, 9-cis, and 13-cis RA isomers are separated, if desired, by an isocratic hexane-dioxane-isopropanol mobile phase. This paper describes an HPLC/MS(n) procedure possessing high sensitivity and specificity for retinoids.

  12. Retinoid quantification by HPLC/MS(n)

    Science.gov (United States)

    McCaffery, Peter; Evans, James; Koul, Omanand; Volpert, Amy; Reid, Kevin; Ullman, M. David

    2002-01-01

    Retinoic acid (RA) mediates most of the biological effects of vitamin A that are essential for vertebrate survival. It acts through binding to receptors that belong to the nuclear receptor transcription factor superfamily (Mangelsdorf et al. 1994). It is also a highly potent vertebrate teratogen. To determine the function and effects of endogenous and exogenous RA, it is important to have a highly specific, sensitive, accurate, and precise analytical procedure. Current analyses of RA and other retinoids are labor intensive, of poor sensitivity, have limited specificity, or require compatibility with RA reporter cell lines (Chen et al. 1995. BIOCHEM: Pharmacol. 50: 1257-1264; Creech Kraft et al. 1994. BIOCHEM: J. 301: 111-119; Lanvers et al. 1996. J. Chromatogr. B Biomed. Appl. 685: 233-240; Maden et al. 1998. DEVELOPMENT: 125: 4133-4144; Wagner et al. 1992. DEVELOPMENT: 116: 55-66). This paper describes an HPLC/mass spectrometry/mass spectrometry product ion scan (HPLC/MS(n)) procedure for the analysis of retinoids that employs atmospheric pressure chemical ionization MS. The retinoids are separated by normal-phase column chromatography with a linear hexane-isopropanol-dioxane gradient. Each retinoid is detected by a unique series of MS(n) functions set at optimal collision-induced dissociation energy (30% to 32%) for all MS(n) steps. The scan events are divided into three segments, based on HPLC elution order, to maximize the mass spectrometer duty cycle. The all-trans, 9-cis, and 13-cis RA isomers are separated, if desired, by an isocratic hexane-dioxane-isopropanol mobile phase. This paper describes an HPLC/MS(n) procedure possessing high sensitivity and specificity for retinoids.

  13. ANALYSIS OF LARGE LC-MS/MS DATASETS USING AMAZON WEB SERVICES AND THE TRANS-PROTEOMIC PIPELINE

    DEFF Research Database (Denmark)

    Slagel, Joseph; Deutsch, Eric; Mendoza, Luis

    Novel Aspect Using cloud computing in conjunction with the TPP provides an expedient, cost effective, and scalable solution for MS/MS data analysis. Introduction The Trans-Proteomic Pipeline (TPP) is a mature and well regarded open source suite of tools for the analysis of large LC-MS/MS datasets...

  14. Development of LC-MS/MS method for analysis of polyphenolic compounds in juice, tea and coffee samples

    Science.gov (United States)

    A simple and fast method for the analysis of a wide range of polyphenolic compounds in juice, tea, and coffee samples was developed using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The method was based on a simple sample preparation “dilute and shoot” approach, and LC-MS/MS triple qu...

  15. High Throughput Analytical Techniques for the Determination and Confirmation of Residues of 653 Multiclass Pesticides and Chemical Pollutants in Tea by GC/MS, GC/MS/MS, and LC/MS/MS: Collaborative Study, First Action 2014.09.

    Science.gov (United States)

    Pang, Guo-Fang; Fan, Chun-Lin; Cao, Yan-Zhong; Yan, Fang; Li, Yan; Kang, Jian; Chen, Hui; Chang, Qiao-Ying

    2015-01-01

    Thirty laboratories from fom North and South America, Europe, and Asia participated in this AOAC collaborative study (15 from China; five from Germany; two each from Italy and the United States; and one each from the Republic of Korea, Canada, Spain, Japan, Belgium, and India). Participants represented government regulatory, commercial testing, university, research institute, and private laboratories. The single-laboratory validated (SLV) tea method was evaluated in the collaborative study to determine the recovery and reproducibility of the method under multilaboratory conditions. Since there were no restrictions regarding the type of analytical instrumentation to use for the analyses, laboratories used a combination of equipment that included GC/MS, GC/MS/MS, and LC/MS/MS instruments from 22 different manufacturers, 21 brands of GC and LC columns, 13 different GC temperature programming profiles, 11 LC gradient elution programs, and six different vendor manufactured SPE cartridges. Even though all the analytical performance parameters for all the 653 compounds had been determined in the SLV study, guidance was obtained from an expert review panel of the AOAC Method-Centric Committee on Pesticide Residues to conduct the multilaboratory collaborative study based on 20 selected compounds that can be analyzed by GC/MS and 20 compounds that can be analyzed by LC/MS/MS. Altogether, 560 samples covering the 40 selected pesticides were analyzed in the study. These samples included green tea and oolong tea samples fortified typically at the European Union maximum residue limit for regulatory guidance and compliance, aged tea samples incurred with 20 pesticides, and green tea and oolong tea samples incurred with five pesticides. The analysis of the 560 samples generated a total of 82 459 test results by the 30 participating laboratories. One laboratory failed to meet the proficiency requirements in the precollaborative study. Therefore, its data submitted for the

  16. Tempest: Accelerated MS/MS Database Search Software for Heterogeneous Computing Platforms.

    Science.gov (United States)

    Adamo, Mark E; Gerber, Scott A

    2016-09-07

    MS/MS database search algorithms derive a set of candidate peptide sequences from in silico digest of a protein sequence database, and compute theoretical fragmentation patterns to match these candidates against observed MS/MS spectra. The original Tempest publication described these operations mapped to a CPU-GPU model, in which the CPU (central processing unit) generates peptide candidates that are asynchronously sent to a discrete GPU (graphics processing unit) to be scored against experimental spectra in parallel. The current version of Tempest expands this model, incorporating OpenCL to offer seamless parallelization across multicore CPUs, GPUs, integrated graphics chips, and general-purpose coprocessors. Three protocols describe how to configure and run a Tempest search, including discussion of how to leverage Tempest's unique feature set to produce optimal results. © 2016 by John Wiley & Sons, Inc. Copyright © 2016 John Wiley & Sons, Inc.

  17. Analytical Method Details (MS): SE52_MS01 [Metabolonote[Archive

    Lifescience Database Archive (English)

    Full Text Available emier). The metabolome analysis and data processing were conducted according to a previously described method (Matsuda...y previously described methods (Matsuda et al., 2009c). Each MS2T entry was assig

  18. LC-MS/MS Analysis Unravels Deep Oxidation of Manganese Superoxide Dismutase in Kidney Cancer

    Science.gov (United States)

    Zhao, Zuohui; Azadzoi, Kazem M.; Choi, Han-Pil; Jing, Ruirui; Lu, Xin; Li, Cuiling; Wang, Fengqin; Lu, Jiaju; Yang, Jing-Hua

    2017-01-01

    Manganese superoxide dismutase (MNSOD) is one of the major scavengers of reactive oxygen species (ROS) in mitochondria with pivotal regulatory role in ischemic disorders, inflammation and cancer. Here we report oxidative modification of MNSOD in human renal cell carcinoma (RCC) by the shotgun method using data-dependent liquid chromatography tandem mass spectrometry (LC-MS/MS). While 5816 and 5571 proteins were identified in cancer and adjacent tissues, respectively, 208 proteins were found to be up- or down-regulated (p kidney cancer due to modifications. Thus, LC-MS/MS analysis revealed multiple oxidative modifications of MNSOD at different amino acid residues that might mediate the regulation of the superoxide radicals, mitochondrial ROS scavenging and MNSOD activity in kidney cancer. PMID:28165386

  19. Method validation and analysis of nine dithiocarbamates in fruits and vegetables by LC-MS/MS

    DEFF Research Database (Denmark)

    Schmidt, Bjørn; Christensen, Hanne Bjerre; Petersen, Annette

    2013-01-01

    An analytical method for separation and quantitative determination of nine dithiocarbamates (DTCs) in fruits and vegetables by using LC-MS/MS was developed, validated and applied to samples purchased in local supermarkets. The nine DTCs were ziram, ferbam, thiram, maneb, zineb, nabam, metiram......, mancozeb and propineb. Validation parameters of mean recovery for two matrices at two concentration levels, relative repeatability (RSDr), relative within-laboratory reproducibility (RSDR) and LOD were obtained for the nine DTCs. The results from the analysis of fruits and vegetables served as the basis...... the various DTCs in the LC-MS/MS analysis was lacking. The exposure and risk assessment showed that only for maneb in the case of apples and apple juice, the acute reference dose was exceeded for infants in the United Kingdom and for children in Germany, respectively....

  20. Analytical Method Details (MS): SE59_MS01 [Metabolonote[Archive

    Lifescience Database Archive (English)

    Full Text Available argeted metabolomic analysis using LC-QTOF-MS and the metabolome data processing of alignment, de-isotoping, noise cutting, and normalization was conducted as previously described. ...

  1. Rapid Determination of Isomeric Benzoylpaeoniflorin and Benzoylalbiflorin in Rat Plasma by LC-MS/MS Method

    Directory of Open Access Journals (Sweden)

    Chuanqi Zhou

    2017-01-01

    Full Text Available Benzoylpaeoniflorin (BP is a potential therapeutic agent against oxidative stress related Alzheimer’s disease. In this study, a more rapid, selective, and sensitive liquid chromatography-tandem mass spectrometric (LC-MS/MS method was developed to determine BP in rat plasma distinguishing with a monoterpene isomer, benzoylalbiflorin (BA. The method showed a linear response from 1 to 1000 ng/mL (r>0.9950. The precision of the interday and intraday ranged from 2.03 to 12.48% and the accuracy values ranged from −8.00 to 10.33%. Each running of the method could be finished in 4 minutes. The LC-MS/MS method was validated for specificity, linearity, precision, accuracy, recovery, and stability and was found to be acceptable for bioanalytical application. Finally, this fully validated method was successfully applied to a pharmacokinetic study in rats following oral administration.

  2. Quantification of phytochelatins in plants by reversed-phase HPLC-ESI-MS-MS.

    Science.gov (United States)

    El-Zohri, M H A; Cabala, R; Frank, H

    2005-08-01

    An on-line HPLC-ESI-MS-MS method has been developed for determination of glutathione and phytochelatins (PC) in plant tissues. For sample pretreatment, dithiothreitol (DTT) must be added at the very beginning, as an anti-oxidant. Optimization of instrumental conditions i.e. composition of HPLC mobile phase, ionization efficiency of the electrospray interface, and MS-MS detection in the multiple ion-monitoring mode, are the central aspects of this work. A polystyrene-packed column was found to be superior to a standard silica-packed reversed-phase column. A concave quadratic gradient of ammonium formate buffer and acetonitrile was found to be optimum. The limits of quantitation were 0.2 micromol kg(-1) plant tissue for glutathione and PC. The method has been applied to analysis of tissue samples from Vicia faba grown in Cd-containing nutrient solutions.

  3. LC-MS/MS quantitation of antimalarial drug piperaquine and metabolites in human plasma.

    Science.gov (United States)

    Aziz, Mohd Yusmaidie; Hoffmann, Kurt-Jürgen; Ashton, Michael

    2017-09-15

    This study aimed to develop a sensitive, quantitative assay for the antimalarial piperaquine (PQ) and its metabolites M1 and M2 in human plasma. Analytes were gradiently separated on a C18 column and detected with a Sciex API 4000 MS/MS with an ESI source operated in the positive ion mode with deuterated PQ as internal standard. The response was linear in the range 3.9-2508nM with a runtime of 7.0min per sample. The method was applied to clinical samples from healthy volunteers. This LC-MS/MS method for the simultaneous quantitation of PQ and two of its metabolites in plasma may prove helpful for assessment of metabolite safety issues in vivo. Copyright © 2017. Published by Elsevier B.V.

  4. MS fragment isotope ratio analysis for evaluation of citrus essential oils by HRGC-MS.

    Science.gov (United States)

    Satake, Atsushi; Furukawa, Kiyoshi; Ueno, Takao; Ukeda, Hiroyuki; Sawamura, Masayoshi

    2004-02-01

    To evaluate the origin of citrus essential oils, the isotope ratio of fragment peaks on HRGC-MS of the volatile compounds from various citrus oils was measured. The MS fragment ratio was found by the ratio of fragment peak intensity, m+1/m (m/z). This ratio reflects the isotope effect of volatile compounds, that is, it provides information about locality, quality, and species for essential oils. Multivariate analysis based on the MS fragment ratio of monoterpene hydrocarbons clearly distinguished three citrus species, yuzu, lemon, and lime. The carbonyl fractions were also extracted from citrus essential oils by the sodium hydrogensulfite method. The isotope ratio of MS fragments of octanal, nonanal, and decanal was also examined. The results suggest that there was no significant difference in the individual fragment isotope ratios of the three aldehydes.

  5. Analytical Method Details (MS): SE56_MS01 [Metabolonote[Archive

    Lifescience Database Archive (English)

    Full Text Available ted for 19.5 min in a single run. The data were recorded using MASSLYNX version 4.1 software (Waters). ...y detection mode for MS detection. In this mode, following acquisition of the MS ... ions were automatically obtained (m/z 50–1000; dwell time 2.5 sec; inter-scan delay 0.5 sec, data acquisition

  6. Quantitation of Total Buprenorphine and Norbuprenorphine in Meconium by LC-MS/MS.

    Science.gov (United States)

    Marin, Stephanie J; McMillin, Gwendolyn A

    2016-01-01

    Buprenorphine (Suboxone, Zubsolv, Buprenex, Butrans, etc.) is an opioid drug that has been used to treat opioid dependence on an outpatient basis, and is also prescribed for managing moderate to severe pain. Pregnant women may be prescribed buprenorphine as part of a treatment plan for opioid addiction. This chapter quantitates buprenorphine and norbuprenorphine in meconium by liquid chromatography tandem mass spectrometry (LC-MS/MS).

  7. Analytical Method Details (MS): SE4_MS3 [Metabolonote[Archive

    Lifescience Database Archive (English)

    Full Text Available SE4_MS3 LC-FT-ICR-MS ESI positive method 3 Agilent1100 HPLC (Agilent), LTQ-FT (Ther...olved in 300uL 80% methanol solution. 20uL sample is injected into HPLC after 0.2um membrane filter treatment. HPLC conditions: Agile...nt 1100 series (Agilent), Column: TSKgel-100V (4.6 x 250 mm, 5 micrometer; TOSOH),

  8. Algorithms for database-dependent search of MS/MS data.

    Science.gov (United States)

    Matthiesen, Rune

    2013-01-01

    The frequent used bottom-up strategy for identification of proteins and their associated modifications generate nowadays typically thousands of MS/MS spectra that normally are matched automatically against a protein sequence database. Search engines that take as input MS/MS spectra and a protein sequence database are referred as database-dependent search engines. Many programs both commercial and freely available exist for database-dependent search of MS/MS spectra and most of the programs have excellent user documentation. The aim here is therefore to outline the algorithm strategy behind different search engines rather than providing software user manuals. The process of database-dependent search can be divided into search strategy, peptide scoring, protein scoring, and finally protein inference. Most efforts in the literature have been put in to comparing results from different software rather than discussing the underlining algorithms. Such practical comparisons can be cluttered by suboptimal implementation and the observed differences are frequently caused by software parameters settings which have not been set proper to allow even comparison. In other words an algorithmic idea can still be worth considering even if the software implementation has been demonstrated to be suboptimal. The aim in this chapter is therefore to split the algorithms for database-dependent searching of MS/MS data into the above steps so that the different algorithmic ideas become more transparent and comparable. Most search engines provide good implementations of the first three data analysis steps mentioned above, whereas the final step of protein inference are much less developed for most search engines and is in many cases performed by an external software. The final part of this chapter illustrates how protein inference is built into the VEMS search engine and discusses a stand-alone program SIR for protein inference that can import a Mascot search result.

  9. LC, MSn and LC-MS/MS studies for the characterization of degradation products of amlodipine

    Institute of Scientific and Technical Information of China (English)

    Ravi N. Tiwari; Nishit Shah; Vikas Bhalani; Anand Mahajan

    2015-01-01

    In the present study, comprehensive stress testing of amlodipine (AM) was carried out according to International Conference on Harmonization (ICH) Q1A(R2) guideline. AM was subjected to acidic, neutral and alkaline hydrolysis, oxidation, photolysis and thermal stress conditions. The drug showed instability in acidic and alkaline conditions, while it remained stable to neutral, oxidative, light and thermal stress. A total of nine degradation products (DPs) were formed from AM, which could be separated by the developed gradient LC method on a C18 column. The products formed under various stress conditions were investigated by LC–MS/MS analysis. The previously developed LC method was suitably modified for LC–MS/MS studies by replacing phosphate buffer with ammonium acetate buffer of the same concentration (pH 5.0). A complete fragmentation pathway of the drug was first established to characterize all the degradation products using LC–MS/MS and multi-stage mass (MSn) fragmentation studies. The obtained mass values were used to study elemental compositions, and the total information helped with the identification of DPs, along with its degradation pathway.

  10. COMPARISON OF COMMERCIAL LC MS/MS COMPATIBLE DETERGENTS WITH SODIUM DEOXYCHOLATE FOR SHOTGUN PROTEOMICS

    Directory of Open Access Journals (Sweden)

    Caleb J. Porter

    2014-12-01

    Full Text Available In this study, we compared the performance of sodium deoxycholate (SDC with several commercially available LC MS/MS compatible detergents for digestion of complex proteomic mixtures. First, the parameters affecting in-solution digestion using SDC were investigated with a full factorial experimental design. Metrics explored were trypsin ratio, digestion time, and concentration of SDC. These parameters were not found to be statistically associated with total peptide identifications in the experimental space investigated. However, in terms of digestion efficiency, digestion time was highly significant (p = 0.0095 as determined by the percent of peptides identified with missed cleavages. The optimized protocol for peptide identification and throughput was used to compare the performance of SDC with various commercially available LC MS/MS compatible surfactants namely Invitrosol, RapiGest, and PPS Silent Surfactant. The detergents were found to be similar through comparisons of the total identified peptides and the hydrophobicity of recovered peptides. We found suitable recovery across a large range of SDC concentrations determined from a bicinchoninic acid (BCA assay. In a spike down experiment, no distinct differences in total number of peptide identifications were discovered when comparing PPS (Silent Surfactant and SDC for preparation of peptide samples derived from low protein amounts (< 20 µg. Combined, these results indicate that SDC is a cost effective alternative to other commonly used LC MS/MS compatible surfactants

  11. Determination of buprenorphine, fentanyl and LSD in whole blood by UPLC-MS-MS.

    Science.gov (United States)

    Berg, Thomas; Jørgenrud, Benedicte; Strand, Dag Helge

    2013-04-01

    A sensitive ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS-MS) method has been developed and validated for the quantification of buprenorphine, fentanyl and lysergic acid diethylamide (LSD) in whole blood. Sample preparation was performed by liquid-liquid extraction (LLE) with methyl tert-butyl ether. UPLC-MS-MS analysis was performed with a mobile phase consisting of ammonium formate (pH 10.2) and methanol. Positive electrospray ionization MS-MS detection was performed with two multiple reaction monitoring transitions for each of the analytes and the deuterium labeled internal standards. Limit of detection values of buprenorphine, fentanyl and LSD were 0.28, 0.044 and 0.0097 ng/mL and limit of quantification values were 0.94, 0.14 and 0.036 ng/mL, respectively. Most phospholipids were removed during LLE. No or only minor matrix effects were observed. The method has been routinely used at the Norwegian Institute of Public Health since September 2011 for qualitative and quantitative detections of buprenorphine, fentanyl and/or LSD in more than 400 whole blood samples with two replicates per sample.

  12. Determination of Aflatoxin B1 in Smokeless Tobacco Products by Use of UHPLC-MS/MS.

    Science.gov (United States)

    Zitomer, Nicholas; Rybak, Michael E; Li, Zhong; Walters, Matthew J; Holman, Matthew R

    2015-10-21

    This work developed a UHPLC-MS/MS method for the detection and quantitation of aflatoxins in smokeless tobacco products, which was then used to determine aflatoxin B1 concentrations in 32 smokeless tobacco products commercially available in the United States. Smokeless tobacco products were dried, milled, and amended with (13)C17-labeled internal standards, extracted in water/methanol solution in the presence of a surfactant, isolated through use of immunoaffinity column chromatography, and reconstituted in mobile phase prior to UHPLC-MS/MS analysis. The method was capable of baseline separation of aflatoxins B1, B2, G1, and G2 in a 2.5 min run by use of a fused core C18 column and a water/methanol gradient. MS/MS transition (m/z) 313.3 → 241.2 was used for aflatoxin B1 quantitation, with 313.3 → 285.1 used for confirmation. The limit of detection (LOD) for aflatoxin B1 was 0.007 parts per billion (ppb). Method imprecision for aflatoxin B1 (expressed as coefficient of variation) ranged from 5.5 to 9.4%. Spike recoveries were 105-111%. Aflatoxin B1 concentrations in the smokeless tobacco products analyzed ranged from snuffs and chews, whereas all moist snuff products tested were below LOD. The amounts of aflatoxin B1 detected were low relative to the 20 ppb regulatory limit established by the U.S. Food and Drug Administration for foods and feeds.

  13. Simultaneous Screening for 45 Poisonous Alkaloids in Blood by LC-MS/MS

    Institute of Scientific and Technical Information of China (English)

    ZHAI Jin-xiao; SHEN Min; LIU Wei

    2015-01-01

    Objective To develop a liquid chromatography-tandem mass spectrometry (LC-MS/MS) screen-ing method for 45 poisonous alkaloids in blood. Methods Identification was based on the compound’s retention time and two precursor-to-production transitions. The method involved a liquid-liquid extraction (LLE) followed by LC-MS/MS with multiple-reaction monitoring (MRM). When 1 mL of blood was ex-tracted with diethyl ether at pH=9.2 with SKF525A as the internal standard, the target compounds were an-alyzed with LC-MS/MS in the positive ionization mode. Results The target alkaloids had good linearity (r>0.995 1), both the intra-day precision and inter-day precision being less than 14.77%. The limits of detection ranged from 0.05 to 25 ng/mL in blood. Conclusion The method is selective and sensitive in detecting poisonous alkaloids with a total running time of 12 minutes; therefore it was successfully ap-plied to some actual cases of suspected alkaloids poisoning.

  14. Ultrafast Polyphenol Metabolomics of Red Wines Using MicroLC-MS/MS.

    Science.gov (United States)

    Ma, Yan; Tanaka, Nobuo; Vaniya, Arpana; Kind, Tobias; Fiehn, Oliver

    2016-01-20

    The taste and quality of red wine are determined by its highly complex mixture of polyphenols and many other metabolites. No single method can fully cover the full metabolome, but even for polyphenols and related compounds, current methods proved inadequate. We optimized liquid chromatography resolution and sensitivity using 1 mm i.d. columns with microLC pumps and compared data-dependent to data-independent (SWATH) MS/MS acquisitions. A high-throughput microLC-MS method was developed with a 4 min gradient at 0.05 mL/min flow rate on a Kinetex C18 column and Sciex TripleTOF mass spectrometry. Using the novel software MS-DIAL, we structurally annotated 264 compounds including 165 polyphenols in six commercial red wines by accurate mass MS/MS matching. As proof of concept, multivariate statistics revealed the difference in the metabolite profiles of the six red wines, and regression analysis linked the polyphenol contents to the taste of the red wines.

  15. Doping control analysis of selected peptide hormones using LC-MS(/MS).

    Science.gov (United States)

    Thevis, Mario; Thomas, Andreas; Schänzer, Wilhelm

    2011-12-10

    With the constantly increasing sensitivity and robustness of liquid chromatography-mass spectrometry-based instruments combined with enhanced reproducibility as well as mass accuracy and resolution, LC-MS(/MS) has become an integral part of sports drug testing programs particularly concerning the detection of peptide hormones. Although several of the relevant peptidic drugs such as insulins (Humalog LisPro, Novolog Aspart, etc.), growth hormone releasing peptides (GHRPs, e.g., GHRP-2, GHRP-6, Hexarelin, etc.), and insulin-like growth factors (e.g., IGF-1, IGF-2, long-R(3)-IGF-1) are currently analyzed using dedicated top-down analytical procedures, i.e. employing specifically tailored sample preparation procedures followed by targeted LC-MS(/MS) measurements focusing on intact analytes, first approaches towards multi-analyte methods have been established. These allow the determination of the prohibited substances in blood and urine doping control specimens following therapeutic applications. In addition, the use of new complementary devices such as ion mobility analyzers, e.g., in hybrid mass spectrometers yielded promising data for the differentiation of isobaric insulins, which outlines the potential to further accelerate and multiplex doping control analytical assays to meet the continuously increasing demands of rapid and unambiguous test methods. Moreover, the potential of LC-MS/MS to target recombinant peptide hormones such as human growth hormone using bottom-up approaches has been demonstrated by targeting proteotypic peptides that unambiguously differentiate the recombinant molecule from the naturally occurring and endogenously produced analog.

  16. LC, MSn and LC–MS/MS studies for the characterization of degradation products of amlodipine

    Directory of Open Access Journals (Sweden)

    Ravi N. Tiwari

    2015-02-01

    Full Text Available In the present study, comprehensive stress testing of amlodipine (AM was carried out according to International Conference on Harmonization (ICH Q1A(R2 guideline. AM was subjected to acidic, neutral and alkaline hydrolysis, oxidation, photolysis and thermal stress conditions. The drug showed instability in acidic and alkaline conditions, while it remained stable to neutral, oxidative, light and thermal stress. A total of nine degradation products (DPs were formed from AM, which could be separated by the developed gradient LC method on a C18 column. The products formed under various stress conditions were investigated by LC–MS/MS analysis. The previously developed LC method was suitably modified for LC–MS/MS studies by replacing phosphate buffer with ammonium acetate buffer of the same concentration (pH 5.0. A complete fragmentation pathway of the drug was first established to characterize all the degradation products using LC–MS/MS and multi-stage mass (MSn fragmentation studies. The obtained mass values were used to study elemental compositions, and the total information helped with the identification of DPs, along with its degradation pathway.

  17. Determination and pharmacokinetics of amygdalin in rats by LC-MS-MS.

    Science.gov (United States)

    Li, Xiao-bo; Liu, Chang-hui; Zhang, Rong; Huang, Xiao-tao; Li, Ying-yi; Han, Liang; Xu, Mei-li; Mi, Sui-qing; Wang, Ning-sheng

    2014-07-01

    A sensitive and specific liquid chromatography-tandem mass spectrometric (LC-MS-MS) method was developed for the determination and pharmacokinetics of amygdalin in rats. Rat plasma pretreated by solid-phase extraction was analyzed by LC-MS-MS with negative electrospray ionization in the multiple reaction monitoring mode. Amygdalin and geniposide [the internal standard (IS)] were separated on a C18 column eluted with a mobile phase of methanol and water (85:15; v/v) at a flow rate of 0.25 mL/min in a run time of 3.0 min. The precursor to product ion transitions were monitored at m/z 457.2 → 279.1 for amygdalin and m/z 387.1 → 224.9 for the IS. The calibration curve of amygdalin showed good linearity over a concentration range of 10-2,000 ng/mL. The limit of quantification was 10 ng/mL. Intra-day and inter-day precisions and accuracy (percent relative standard deviation) were both within 10%. The method was fully validated for its selectivity, sensitivity, matrix effect, recovery and stability. This accurate and specific assay produced a useful LC-MS-MS method, which was successfully applied to pharmacokinetic studies after the oral administration of amygdalin to rats. © The Author [2013]. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  18. LC-MS-based metabolomics: an update.

    Science.gov (United States)

    Fang, Zhong-Ze; Gonzalez, Frank J

    2014-08-01

    Liquid chromatography-mass spectrometry (LC-MS)-based metabolomics can have a major impact in multiple research fields, especially when combined with other technologies, such as stable isotope tracers and genetically modified mice. This review highlights recent applications of metabolomic technology in the study of xenobiotic metabolism and toxicity, and the understanding of disease pathogenesis and therapeutics. Metabolomics has been employed to study metabolism of noscapine, an aryl hydrocarbon receptor antagonist, and to determine the mechanisms of liver toxicities of rifampicin and isoniazid, trichloroethylene, and gemfibrozil. Metabolomics-based insights into the pathogenesis of inflammatory bowel disease, alcohol-induced liver diseases, non-alcoholic steatohepatitis, and farnesoid X receptor signaling pathway-based therapeutic target discovery will also be discussed. Limitations in metabolomics technology such as sample preparation and lack of LC-MS databases and metabolite standards, need to be resolved in order to improve and broaden the application of metabolomic studies.

  19. CT-Guided Trigeminal Neuralgia in MS

    Directory of Open Access Journals (Sweden)

    Jalal Jalal Shokouhi

    2011-05-01

    Full Text Available Background/Objective: Multiple sclerosis has nonspecific"nsigns in MR images and clinic and also has pain,"none of the pain syndromes in MS cases is trigeminal"nneuralgia. 12 patients of our 38 trigeminal neuralgic"npatients etiology were known as MS cases. All of them"nwere young (20-40 years old."nIntroduction: Multiple sclerosis diagnosis is by clinic,"nMRI, CSF electrophoresis and evocked potensial tests."nImaging diagnostis is not suggestive and specific but in"nthis article we show imaging help not only in diagnosis"nalso in treatment of complications. Trigeminal neuralgia"nis the worse clinical condition in M.S patients and may"npush them to addiction or suicide."nMaterials and Methods: X-ray CT machine is used for"nguidance of L.P or coaxial 10cm needle with 22G, local"nanesthesia and ethanol injection. One time treatment"nmade for all patients and they were pain free after"ninterventional drug injection. 5-6 cc bupivicain 0.5%"nand 3-4cc ethanol 96% are used for treatment."nResults: All patients were pain free and very happy"nafter treatment. One of them had pain for 12 years"nand had tried all the other treatments with no good"nresponse. No complication was seen in our treatments."n15 to 20 minutes time is needed for each examination"nor treatment."nConclusion: Despite known MS cases and relative"ndrug therapies for patients it is not possible to treat"ntrigeminal paint except using interventional therapy"nand CT-guidance is exactive and easy. There was"nno complication except irritation in the middle ear"nbecause of Eustachian tube compression by injected"nvolume of drugs

  20. Petroleomics by EASI(+/-) FT-ICR MS.

    Science.gov (United States)

    Corilo, Yuri E; Vaz, Boniek G; Simas, Rosineide C; Nascimento, Heliara D Lopes; Klitzke, Clécio F; Pereira, Rosana C L; Bastos, Wagner L; Santos Neto, Eugênio V; Rodgers, Ryan P; Eberlin, Marcos N

    2010-05-15

    An ambient ionization/desorption technique, namely, easy ambient sonic-spray ionization mass spectrometry (EASI), has been applied to crude oil samples. From a single droplet of the sample placed on an inert surface, EASI(+/-) is shown to promote efficient desorption and ionization of a myriad of polar components via the action of its cloud of very minute supersonic bipolar charged droplets. The gaseous [M + H](+) and [M - H](-) ions concurrently formed by EASI(+/-) were analyzed by Fourier transform mass spectrometry (FT-ICR MS), and a total of approximately 6000 acidic and basic components have been attributed. EASI(+/-) FT-ICR MS of crude oils is show to be almost as fast as ESI(+)/ESI(-) FT-ICR MS, providing similar compositional information of polar components and spectral quality comparable to that of a commercial nonochip-based robotic ESI device. EASI(+/-) requires no sample workup thus eliminating risks of contamination during sample manipulation and memory effects because of carry over in pumping ESI lines. More importantly, EASI(+/-) is a voltage-free ionization technique therefore eliminating risks of redox processes or duality of ionization mechanisms that can be observed in voltage-assisted processes. Data visualization via typical petroleomic plots confirms the similarity of the compositional information provided by EASI(+/-) compared to ESI(+)/ESI(-). The ambient EASI(+/-) FT-ICR MS method requires no voltage switching in changing the ion polarity mode, offering a workup, heating and voltage-free protocol for petroleomic studies performed at open atmosphere directly on the undisturbed crude oil sample.

  1. Economic costs associated with an MS relapse

    LENUS (Irish Health Repository)

    O'Connell, K.

    2014-09-01

    This was an prospective audit composed of medical chart review and patient questionnaire. Relapses were stratified into 3 groups: low, moderate and high intensity. Age, gender, MS subtype, disease duration, expanded disability status scale (EDSS) score, disease modifying therapy (DMT) use and employment status were recorded. Direct costs included GP visits, investigations, clinic visit, consultations with medical staff, medication and admission costs. Indirect costs assessed loss of earnings, partner\\'s loss of earnings, childcare, meals and travel costs.

  2. Familiar Face Detection in 180ms

    Science.gov (United States)

    Visconti di Oleggio Castello, Matteo; Gobbini, M. Ida

    2015-01-01

    The visual system is tuned for rapid detection of faces, with the fastest choice saccade to a face at 100ms. Familiar faces have a more robust representation than do unfamiliar faces, and are detected faster in the absence of awareness and with reduced attentional resources. Faces of family and close friends become familiar over a protracted period involving learning the unique visual appearance, including a view-invariant representation, as well as person knowledge. We investigated the effect of personal familiarity on the earliest stages of face processing by using a saccadic-choice task to measure how fast familiar face detection can happen. Subjects made correct and reliable saccades to familiar faces when unfamiliar faces were distractors at 180ms—very rapid saccades that are 30 to 70ms earlier than the earliest evoked potential modulated by familiarity. By contrast, accuracy of saccades to unfamiliar faces with familiar faces as distractors did not exceed chance. Saccades to faces with object distractors were even faster (110 to 120 ms) and equivalent for familiar and unfamiliar faces, indicating that familiarity does not affect ultra-rapid saccades. We propose that detectors of diagnostic facial features for familiar faces develop in visual cortices through learning and allow rapid detection that precedes explicit recognition of identity. PMID:26305788

  3. LC-MS-MS and GC-MS analyses of biologically active extracts and fractions from Tunisian Juniperus phoenice leaves.

    Science.gov (United States)

    Keskes, Henda; Belhadj, Sahla; Jlail, Lobna; El Feki, Abdelfattah; Damak, Mohamed; Sayadi, Sami; Allouche, Noureddine

    2017-12-01

    Despite some studies related to Juniperus phoenicea L. (Cupressaceae), phytochemical and biological investigations of this plant remain unexplored. This work is the first report dealing with the identification and characterization of volatile components and flavonoids in hexane and methanol extracts from J. phoenicea leaves Materials and methods: Antioxidant activity of hexane, and methanol extracts from J. phoenicea leaves were determined by DPPH-radical scavenging assay. α-Amylase inhibitory activity was evaluated by enzyme inhibition using in vitro assay (each extract was dissolved in DMSO to give concentrations of 50, 100 and 200 mg/mL). The chemical composition of fractions (Fr1-Fr3) from methanol extract was determined by high-performance liquid chromatography coupled with mass spectroscopy (HPLC-MS) analysis. The hexane extract was analyzed by GC-MS technique which allowed the identification of 32 compounds. The main constituents were α-humulene (16.9%), pentadecane (10.2%) and α-cubebene (9.7%). Fraction Fr 2 exhibited a strong DPPH radical-scavenging activity (IC50 = 20.1 μg/mL) compared to that of BHT as well as the highest α-amylase inhibitory activity (IC50 = 28.4 μg/mL). Three flavonoids were identified in these fractions using HPLC-MS analysis: Quercetin 3-O-glucoside, isoscutellarein 7-O-pentoside and quercetin 3-O-pentoside. In addition, the more active fraction (Fr 2) was purified with semi-preparative HPLC affording one pure compound (amentoflavone) using (1)H NMR analysis. This compound exhibited powerful DPPH radical-scavenging (IC50 = 14.1 μg/mL) and α-amylase inhibition (IC50 = 20.4 μg/mL) effects. This study provides scientific support to some medicinal uses of J. phoenicea found in North Africa.

  4. LC-MS-MS Method for Stimulants in Wastewater During Football Games.

    Science.gov (United States)

    Gul, Waseem; Stamper, Brandon J; Godfrey, Murrell; ElSohly, Mahmoud A

    2016-03-01

    A method was developed for the analysis of amphetamines and cocaine (Coc) in wastewater samples using liquid chromatography coupled with tandem mass spectrometry (LC-MS-MS). Seven stimulant-type drugs and metabolites were analyzed. These drugs included amphetamine (Amp), methamphetamine (Meth), methylenedioxyamphetamine (MDA), methylenedioxymethamphetamine (MDMA), methylenedioxyethylamphetamine (MDEA), Coc and benzoylecgonine (BE, the major metabolite of Coc). These drugs were chosen because of their widespread use. Wastewater samples were collected at both the Oxford Waste Water Treatment Plant in Oxford, Mississippi (MS) and the University Wastewater Treatment Plant in University, MS. Samples were collected on weekends in which the Ole Miss Rebel football team held home games (Vaught-Hemingway Stadium, University, MS 38677). The collected samples were analyzed using a validated method and found to contain Amp, Meth, MDMA, Coc and BE. The concentrations of Amp and BE significantly rose in the university wastewater during football games. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  5. Determination of 48 fragrance allergens in toys using GC with ion trap MS/MS.

    Science.gov (United States)

    Lv, Qing; Zhang, Qing; Li, Wentao; Li, Haiyu; Li, Pi; Ma, Qiang; Meng, Xianshuang; Qi, Meiling; Bai, Hua

    2013-11-01

    This paper presents a method for the simultaneous determination of 48 fragrance allergens in four types of toys (plastic toys, play clays, plush toys, and paper toys) based on GC with ion trap MS/MS. Compared with single-stage MS, MS/MS is superior in terms of the qualification and quantification of a large range of compounds in complicated matrices. Procedures for extraction and purification were optimized for each toy type. The method proved to be linear over a wide range of concentrations for all analytes with correlation coefficients between 0.9768 and 0.9999. Validation parameters, namely, LODs and LOQs, ranged from 0.005-5.0 and from 0.02-20 mg/kg, respectively. Average recoveries of target compounds (spiked at three concentration levels) were in the range of 79.5-109.1%. Intraday and interday repeatabilities of the proposed method varied from 0.7-10.5% and from 3.1-13.4%, respectively. The proposed method was used to monitor fragrance allergens in commercial toy products. Our findings indicate that this method is an accurate and effective technique for analyzing fragrance allergens in materials composed of complex components.

  6. SWATH Mass Spectrometry Performance Using Extended Peptide MS/MS Assay Libraries.

    Science.gov (United States)

    Wu, Jemma X; Song, Xiaomin; Pascovici, Dana; Zaw, Thiri; Care, Natasha; Krisp, Christoph; Molloy, Mark P

    2016-07-01

    The use of data-independent acquisition methods such as SWATH for mass spectrometry based proteomics is usually performed with peptide MS/MS assay libraries which enable identification and quantitation of peptide peak areas. Reference assay libraries can be generated locally through information dependent acquisition, or obtained from community data repositories for commonly studied organisms. However, there have been no studies performed to systematically evaluate how locally generated or repository-based assay libraries affect SWATH performance for proteomic studies. To undertake this analysis, we developed a software workflow, SwathXtend, which generates extended peptide assay libraries by integration with a local seed library and delivers statistical analysis of SWATH-quantitative comparisons. We designed test samples using peptides from a yeast extract spiked into peptides from human K562 cell lysates at three different ratios to simulate protein abundance change comparisons. SWATH-MS performance was assessed using local and external assay libraries of varying complexities and proteome compositions. These experiments demonstrated that local seed libraries integrated with external assay libraries achieve better performance than local assay libraries alone, in terms of the number of identified peptides and proteins and the specificity to detect differentially abundant proteins. Our findings show that the performance of extended assay libraries is influenced by the MS/MS feature similarity of the seed and external libraries, while statistical analysis using multiple testing corrections increases the statistical rigor needed when searching against large extended assay libraries.

  7. Development and validation of analytical method for Naftopidil in human plasma by LC–MS/MS

    Directory of Open Access Journals (Sweden)

    Pritam S. Jain

    2015-09-01

    Full Text Available A highly sensitive and simple high-performance liquid chromatographic–tandem mass spectrometric (LC–MS-MS assay is developed and validated for the quantification of Naftopidil in human plasma. Naftopidil is extracted from human plasma by methyl tertiary butyl ether and analyzed using a reversed-phase gradient elution on a discovery C 18 5 μ (50 × 4.6 column. A methanol: 2 mM ammonium formate (90:10 as mobile phase, is used and detection was performed by MS using electrospray ionization in positive mode. Propranolol is used as the internal standard. The lower limits of quantification are 0.495 ng/mL. The calibration curves are linear over the concentration range of 0.495–200.577 ng/mL of plasma for each analyte. This novel LC–MS-MS method shows satisfactory accuracy and precision and is sufficiently sensitive for the performance of pharmacokinetic studies in humans.

  8. SweetNET: A Bioinformatics Workflow for Glycopeptide MS/MS Spectral Analysis.

    Science.gov (United States)

    Nasir, Waqas; Toledo, Alejandro Gomez; Noborn, Fredrik; Nilsson, Jonas; Wang, Mingxun; Bandeira, Nuno; Larson, Göran

    2016-08-01

    Glycoproteomics has rapidly become an independent analytical platform bridging the fields of glycomics and proteomics to address site-specific protein glycosylation and its impact in biology. Current glycopeptide characterization relies on time-consuming manual interpretations and demands high levels of personal expertise. Efficient data interpretation constitutes one of the major challenges to be overcome before true high-throughput glycopeptide analysis can be achieved. The development of new glyco-related bioinformatics tools is thus of crucial importance to fulfill this goal. Here we present SweetNET: a data-oriented bioinformatics workflow for efficient analysis of hundreds of thousands of glycopeptide MS/MS-spectra. We have analyzed MS data sets from two separate glycopeptide enrichment protocols targeting sialylated glycopeptides and chondroitin sulfate linkage region glycopeptides, respectively. Molecular networking was performed to organize the glycopeptide MS/MS data based on spectral similarities. The combination of spectral clustering, oxonium ion intensity profiles, and precursor ion m/z shift distributions provided typical signatures for the initial assignment of different N-, O- and CS-glycopeptide classes and their respective glycoforms. These signatures were further used to guide database searches leading to the identification and validation of a large number of glycopeptide variants including novel deoxyhexose (fucose) modifications in the linkage region of chondroitin sulfate proteoglycans.

  9. Validation of an HPLC-MS/MS and wipe procedure for mitomycin C contamination.

    Science.gov (United States)

    B'Hymer, Clayton; Connor, Thomas; Stinson, Derek; Pretty, Jack

    2015-04-01

    A high-performance liquid chromatography-tandem mass spectrometric (HPLC-MS/MS) method was developed for the determination of mitomycin C, an anticancer drug, from contamination on various surfaces. Mitomycin C is often used in various forms of intraperitoneal chemotherapy, and operating room healthcare worker exposure to this drug is possible. The surface testing method consisted of a wiping procedure utilizing a solution of 20/45/35 (v/v/v) of acetonitrile-isopropanol-water made 0.01 M in ammonium citrate (apparent pH 7.0). The wipe solutions were analyzed by means of HPLC-MS/MS using a reversed-phase gradient system and electrospray ionization in positive ion mode with a triple-quadrupole MS detector. Accuracy and precision of this method were demonstrated by a series of recovery studies of both spiked solutions and extracted wipes from various surfaces (stainless steel, vinyl and Formica(®)) spiked with known levels of mitomycin C. Recoveries of spiked solutions containing the analyte demonstrate mean recoveries (accuracy) ranged from 93 to 105%. Precision as measured by the relative standard deviation (% RSD) of multiple samples (n= 10) at each concentration level demonstrated values of 7.5% or less. The recoveries from spiked surfaces varied from 30 to 99%. The limit of detection for this methodology is ∼2 ng/100 cm(2) equivalent surface area, and the limit of quantitation is ∼6 ng/100 cm(2).

  10. Characterization of cocoa liquors by GC-MS and LC-MS/MS: focus on alkylpyrazines and flavanols.

    Science.gov (United States)

    Magi, Emanuele; Bono, Luca; Di Carro, Marina

    2012-09-01

    Flavor is one of the most important characteristics of chocolate products and is due to a complex volatile fraction, depending both on the cocoa bean genotype and the several processes occurring during chocolate production (fermentation, drying, roasting and conching). Alkylpyrazines are among the most studied volatiles, being one of the main classes of odorant compounds in cocoa products. In this work, a mass spectrometric approach was used for the comparison of cocoa liquors from different countries. A headspace solid-phase microextraction gas chromatography-mass spectrometry method was developed for the qualitative study of the volatile fraction; the standard addition method was then used for the quantitative determination of five pyrazines (2-methylpyrazine, 2,3-dimethylpyrazine, 2,5-dimethylpyrazine, 2,3,5-trimethylpyrazine and tetramethylpyrazine). Satisfactory figures of merit were obtained: Limits of quantitation were in the range 0.1-2.7 ng/g; repeatability and reproducibility varied between 3% and 7% and between 8% and 14%, respectively. The total content of the pyrazines was remarkably different in the considered samples, ranging from 99 to 708 ng/g. Tetramethylpyrazine showed the highest concentration in all samples, with a maximum value of 585 ng/g. A preliminary study was also performed on the nonvolatile fraction using LC-MS/MS, identifying some flavanols such as catechin, epicatechin and procyanidins.

  11. Simultaneous quantification of the organophosphorus pesticides dimethoate and omethoate in porcine plasma and urine by LC-ESI-MS/MS and flow-injection-ESI-MS/MS.

    Science.gov (United States)

    John, Harald; Eddleston, Michael; Clutton, R Eddie; Worek, Franz; Thiermann, Horst

    2010-05-15

    Dimethoate is an organophosphorus toxicant used in agri- and horticulture as a systemic broad-spectrum insecticide. It also exhibits toxic activity towards mammalian organism provoked by catalytic desulfuration in the liver producing its oxon-derivative omethoate thus inhibiting acetylcholinesterase, initiating cholinergic crisis and ultimately leading to death by respiratory paralysis and cardiovascular collapse. Pharmaco- and toxicokinetic studies in animal models help to broaden basic understanding of medical intervention by antidotes and supportive care. Therefore, we developed and validated a LC-ESI-MS/MS method suitable for the simultaneous, selective, precise (RSD(intra-day) 1-8%; RSD(inter-day) 5-14%), accurate (intra-day: 95-107%; inter-day: 90-115%), and robust quantification of both pesticides from porcine urine and plasma after deproteinization by precipitation and extensive dilution (1:11,250 for plasma and 1:40,000 for urine). Accordingly, lower limits of quantification (0.24-0.49 microg/ml plasma and 0.78-1.56 microg/ml urine) and lower limits of detection (0.12-0.24 microg/ml plasma and 0.39-0.78 microg/ml urine) were equivalent to quite low absolute on-column amounts (1.1-2.1 pg for plasma and 2.0-3.9 pg for urine). The calibration range (0.24-250 microg/ml plasma and 0.78-200 microg/ml urine) was subdivided into two linear ranges (r(2)>or=0.998) each covering nearly two orders of magnitude. The lack of any interfering peak in 6 individual blank specimens from plasma and urine demonstrated the high selectivity of the method. Furthermore, extensive sample dilution causing lowest concentration of potentially interfering matrix ingredients prompted us to develop and validate an additional flow-injection method (FI-ESI-MS/MS). Validation characteristics were as good as for the chromatographic method but sample throughput was enhanced by a factor of 6. Effects on ionization provoked by plasma and urine matrix from 6 individuals as well as in the

  12. Identification and quantification of carotenoids, by HPLC-PDA-MS/MS, from Amazonian fruits.

    Science.gov (United States)

    de Rosso, Veridiana V; Mercadante, Adriana Z

    2007-06-27

    The major and minor carotenoids from six fruits, buriti (Mauritia vinifera), mamey (Mammea americana), marimari (Geoffrola striata), peach palm (Bactrys gasipaes), physalis (Physalis angulata), and tucuma (Astrocaryum aculeatum), all native to the Amazonia region, were determined by high-performance liquid chromatography-photodiode array detector-mass spectrometry detector (HPLC-PDA-MS/MS), fulfilling the recommended criteria for identification. A total of 60 different carotenoids were separated on a C30 column, all-trans-beta-carotene being the major carotenoid found in all fruits. The presence of apo-10'-beta-carotenol, found in mamey, was not previously reported in foods. In addition, this is the first time that the identification of beta-zeacarotene in natural sources is supported by MS data. The total carotenoid content ranged from 38 microg/g in marimari to 514 microg/g in buriti. All fruits analyzed can be considered good sources of provitamin A, especially buriti, with 7280 RE/100 g.

  13. Identification of chemical markers in Cordyceps sinensis by HPLC-MS/MS.

    Science.gov (United States)

    Hu, Hankun; Xiao, Ling; Zheng, Baogen; Wei, Xin; Ellis, Alexis; Liu, Yi-Ming

    2015-10-01

    Authentication and quality assessment of Cordyceps sinensis, a precious and pricey natural product that offers a variety of health benefits, is highly significant. To identify effective chemical markers, authentic C. sinensis was thoroughly screened by using HPLC-MS/MS. In addition to many previously reported ingredients, two glycosides, i.e., cyclo-Ala-Leu-rhamnose and Phe-o-glucose, were detected for the first time in this material. Six ingredients detected, including cordycepin, D-mannitol, Phe, Phe-o-glucose, cyclo-Gly-Pro, and cyclo-Ala-Leu-rhamnose, were selected as a collection of chemical markers. An HPLC-MS/MS method was developed to simultaneously quantify them with sensitivity and specificity. The method had limits of detection ranging from 0.008 μg mL(-1) for cordycepin to 0.75 μg mL(-1) for cyclo-Gly-Pro. Recovery was found between 96 and 103 % in all tests. To evaluate the effectiveness of the marker collection proposed, five authentic C. sinensis samples and five samples of its substitutes were analyzed. Cordycepin, D-mannitol, and Phe were found present in all samples. The contents ranged from 0.0076 to 0.029 % (w/w) for cordycepin, 0.33 to 18.9 % for mannitol, and 0.0013 to 0.642 % for Phe. Interestingly, the two glycosides, Phe-o-glucose and cyclo-Ala-Leu-rhamnose, were detected only in authentic C. sinensis samples. These results indicated that the proposed protocol based on HPLC-MS/MS quantification of the markers might have a great potential in authentication and quality assessment of C. sinensis. Graphical abstract Chemical markers of C. sinensis identified in this work.

  14. UFLC-ESI-MS/MS analysis of multiple mycotoxins in medicinal and edible Areca catechu.

    Science.gov (United States)

    Liu, Hongmei; Luo, Jiaoyang; Kong, Weijun; Liu, Qiutao; Hu, Yichen; Yang, Meihua

    2016-05-01

    A robust, sensitive and reliable ultra fast liquid chromatography combined with electrospray ionization tandem mass spectrometry (UFLC-ESI-MS/MS) was optimized and validated for simultaneous identification and quantification of eleven mycotoxins in medicinal and edible Areca catechu, based on one-step extraction without any further clean-up. Separation and quantification were performed in both positive and negative modes under multiple reaction monitoring (MRM) in a single run with zearalanone (ZAN) as internal standard. The chromatographic conditions and MS/MS parameters were carefully optimized. Matrix-matched calibration was recommended to reduce matrix effects and improve accuracy, showing good linearity within wide concentration ranges. Limits of quantification (LOQ) were lower than 50 μg kg(-1), while limits of detection (LOD) were in the range of 0.1-20 μg kg(-1). The accuracy of the developed method was validated for recoveries, ranging from 85% to 115% with relative standard deviation (RSD) ≤14.87% at low level, from 75% to 119% with RSD ≤ 14.43% at medium level and from 61% to 120% with RSD ≤ 13.18% at high level, respectively. Finally, the developed multi-mycotoxin method was applied for screening of these mycotoxins in 24 commercial samples. Only aflatoxin B2 and zearalenone were found in 2 samples. This is the first report on the application of UFLC-ESI(+/-)-MS/MS for multi-class mycotoxins in A. catechu. The developed method with many advantages of simple pretreatment, rapid determination and high sensitivity is a proposed candidate for large-scale detection and quantification of multiple mycotoxins in other complex matrixes.

  15. Development and clinical application of an LC-MS-MS method for mescaline in urine.

    Science.gov (United States)

    Björnstad, Kristian; Helander, Anders; Beck, Olof

    2008-04-01

    Mescaline (3,4,5-trimethoxyphenylethylamine) is an hallucinogenic psychoactive substance present in several species of cacti. Mescaline has a documented use dating back 5700 years. In more recent years, the interest in hallucinogenic designer drugs such as ecstasy has also triggered interest in the naturally occurring mescaline. This study was undertaken to develop a liquid chromatography-tandem mass spectrometry (LC-MS-MS) method for the screening and confirmation of mescaline in human urine samples and to apply this method to routine testing in patient samples. For the screening procedure, chromatographic separation was achieved on a 5-microm HyPURITY C(18) column, using a methanol gradient in ammonium acetate buffer. The MS-MS analysis was performed using selected reaction monitoring; the transitions monitored were m/z 212.3 --> m/z 180.3 for mescaline and m/z 221.3 --> m/z 186.3 for the deuterated internal standard (mescaline-d(9)). The detection limit for mescaline in urine matrix was 3-5 microg/L, the upper limit of quantification was 10,000 microg/L, and the total coefficient of variation for spiked samples containing 10 to 1025 microg/L was mescaline (m/z 212.3 --> m/z 195.2) was monitored. The LC-MS-MS method was found to be sensitive and specific for the routine detection of mescaline in urine. Among 462 urine samples collected from young people with alcohol or drug problems, 32% were positive for illicit drugs, but none for mescaline.

  16. [Simultaneous determination of 11 mycotoxins in malt by isotope internal standard-UPLC-MS/MS].

    Science.gov (United States)

    Wang, Sha; Kong, Wei-jun; Yang, Mei-hua

    2016-01-01

    A suitable ultra-high performance liquid chromatography coupled with tandem mass spectrometry (UPLC-MS/MS) method was developed for the determination of 11 mycotoxins with isotope internal standard in malt. The mycotoxins in malt were extracted and purified by one-step ultrasonic extraction procedure using acetonitrile/water/acetic acid (80 : 19 : 1), and then detected and confirmed by UPLC-MS/MS, and quantified by isotope labeled AFB1 ([13C17]-AFB1) and ZEN ([13C18]-ZEN) internal standards. Rapid separation of the 11 mycotoxins was successfully achieved on a Phenomenex Kinetex C18 column (100 mm x 2.1 mm, 2.6 μm) with gradient elution using the mobile phase of methanol containing 0.1% formic acid and 2 mmol x L(-1) ammonium acetate in water. Simultaneous acquisition was performed in multiple reaction monitoring (MRM) mode with electrospray ionization (ESI) source operated in both positive and negative ionization modes. The established method provided a good linearity for the 11 mycotoxins within their respective linear ranges with correlation coefficients all higher than 0.999 1. The average recoveries ranged from 75.0% to 117.0% with relative standard deviations (RSDs) below 5.1%. The limits of detection (LODs) and quantitation (LOQs) ranged from 0.05 to 30 μg x kg(-1) and 0.15 to 87.5 μg x kg(-1), respectively, which were below the maximum residue levels (MRLs) set by the European Union. Twenty malt samples were analyzed and nine samples were detected with mycotoxins, which were confirmed according to the same fragment ions found in positive samples and the standards at the same retention time. This study has demonstrated that the one-step extraction procedure of mycotoxins from complex matrices coupled to UPLC-MS/MS method is simple, quick, accurate and sensitive for quantitative and qualitative analysis of multiple mycotoxins in malt.

  17. Measures of visual pathway structure and function in MS: Clinical usefulness and role for MS trials.

    Science.gov (United States)

    Galetta, Kristin M; Balcer, Laura J

    2013-07-01

    Over the past decade, the visual pathway in multiple sclerosis (MS) has become an important system for assessing both patient function and disease burden. Abnormalities of low-contrast acuity, long recognized as important correlates of driving, facial recognition, and other activities of daily living, are now noted to be common among patients with MS, even among those with no history of acute optic neuritis (ON). Low-contrast letter acuity scores correlate well with brain MRI lesion burden, visual-evoked potential (VEP) amplitudes, health-related quality of life (QOL), and retinal nerve fiber layer (RNFL) axonal and neuronal loss as measured by optical coherence tomography (OCT). Axonal and neuronal degeneration in MS is likely to be an important cause of visual impairment and disability, particularly among patients with progressive MS subtypes. With the advent of OCT and the use of low-contrast letter acuity charts in MS research and clinical trials, the structure-function correlations afforded by the anterior visual pathway can be assessed and potentially harnessed as a model for testing new therapies. Recent advances in OCT, such as high resolution spectral-domain techniques and computerized algorithms for image analysis, have allowed for measurement of specific retinal layers, including the ganglion cell (GCL) neuronal layer and its intimately associated, thin layer of interneurons, the inner plexiform layer (IPL). Longitudinal collaborative studies of GCL+IPL thinning and RNFL axonal loss are providing an in vivo view into neuroretinal pathology, and are providing new insights into how the visual pathway may reflect overall mechanisms of disease in MS. Copyright © 2012 Elsevier B.V. All rights reserved.

  18. Analysis of benzodiazepines and their metabolites using DBS cards and LC-MS/MS.

    Science.gov (United States)

    Lee, Heesang; Park, Yujin; Jo, Jiyeong; In, Sangwhan; Park, Yonghoon; Kim, Eunmi; Pyo, Jaesung; Choe, Sanggil

    2015-10-01

    Dried Blood Spot (DBS) has been used a blood extraction method for inherited metabolic disorder screening since 1960s. With introduction of LC-MS/MS, not only DBS could be used to analysis drugs in small blood volume, but in various fields, such as toxicology, drug therapeutic monitoring, drug diagnostic screening, and illicit drugs. In toxicology field, many drugs (e.g. benzodiazepines, acetaminophen, small molecule drugs) have been tested with DBS. Compared with earlier blood extraction methods (SPE and LLE), DBS has lots of advantages; lower blood volume (less than 50μL), shorter analysis time caused by a more concise analysis procedure and lower cost. We optimized the DBS procedure and LC-MS/MS conditions for 18 benzodiazepines, seven benzodiazepine metabolites, and one z-drug (zolpidem) analysis in blood. 30μL of whole blood was spotted on FTA DMPK card C and dried for 2h in a desiccator. A 6-mm disk was punched and vortexed for 1min in a centrifuge tube with 300μL methanol/acetonitrile mixture (1:1, v/v). After evaporation, redissolved in 100μL mobile phase of LC-MS/MS and 5μL was injected. In the analysis for 26 target compounds in blood, all of the method validation parameters - LLOD, LLOQ, accuracy (intra- and inter-assay), and precision (intra- and inter-assay) - were satisfied with method validation criteria, within 15%. The results of matrix effect, recovery, and process efficiency were good. We developed a fast and reliable sample preparation method using DBS for 26 benzodiazepines, benzodiazepine metabolites, and z-drug (zolpidem).

  19. Short Communication: Testosterone Measured with an Automatic Immunoassay Compares Reasonbly Well to Results Obtained by LC-MS/MS

    DEFF Research Database (Denmark)

    Knudsen, Cindy Søndersø; Højskov, Carsten Schriver; Møller, Holger Jon

    2016-01-01

    hormonebinding globulin (SHBG), and albumin employing Cobas e601/c501. Testosterone, androstenedione (andro), dehydroepiandrosterone sulphate (DHEAS), and 17-hydroxyprogesterone (17-OHP) concentrations were measured employing LC-MS/MS. We evaluated the difference between testosterone measured by the two methods...... for the difference between results obtained by the two methods and the sample concentration of DHEAS and andro: Diff (Cobas e601 - LC-MS/MS) = 0.116 x DHEAS - 0.396, r = 0.84 and Diff (Cobas e601 - LC-MS/MS) = 0.08 andro - 0.380, r = 0.58. No statistically significant interference was observed for progesterone, 17......-OHP, SHBG, and albumin. Conclusions: We report significant differences between testosterone measurements employing an automatic second generation immunoassay and LC-MS/MS. The difference can be correlated with the measured concentrations of DHEAS and andro, and its magnitude is judged to be of limited...

  20. UPLC-MS/MS determination of ptaquiloside and pterosin B in preserved natural water

    DEFF Research Database (Denmark)

    Clauson-Kaas, Frederik; Hansen, Hans Chr. Bruun; Strobel, Bjarne W.

    2016-01-01

    The naturally occurring carcinogen ptaquiloside and its degradation product pterosin B are found in water leaching from bracken stands. The objective of this work is to present a new sample preservation method and a fast UPLC-MS/MS method for quantification of ptaquiloside and pterosin B...... at realistic transportation and storing conditions prior to extraction. Groundwater samples collected in November 2015 at the shallow water table below a Danish bracken stand were preserved and analyzed using the above methods, and PTA concentrations of 3.8 ± 0.24 μg/L (±sd, n = 3) were found, much higher than...

  1. Quantitative analysis of methyl and propyl parabens in neonatal DBS using LC-MS/MS.

    Science.gov (United States)

    Yakkundi, Shirish; Mulla, Hussain; Pandya, Hitesh; Turner, Mark A; McElnay, James

    2016-06-01

    Excipients are used to overcome the chemical, physical and microbiological challenges posed by developing formulated medicines. Both methyl and propyl paraben are commonly used in pediatric liquid formulations. There is no data on systemic exposure to parabens in neonates. The European Study of Neonatal Exposure to Excipients project has investigated this. Results & methodology: DBS sampling was used to collect opportunistic blood samples. Parabens were extracted from the DBS and analyzed using a validated LC-MS/MS assay. The above assay was applied to analyze neonatal DBS samples. The blood concentrations of parabens in neonates confirm systemic exposure to parabens following administration of routine medicines.

  2. Statistical Assessment of QC Metrics on Raw LC-MS/MS Data.

    Science.gov (United States)

    Wang, Xia

    2017-01-01

    Data quality assessment is important for reproducibility of proteomics experiments and reusability of proteomics data. We describe a set of statistical tools to routinely visualize and examine the quality control (QC) metrics obtained for raw LC-MS/MS data on different instrument types and mass spectrometers. The QC metrics used here are the identification free QuaMeter metrics. Statistical assessments introduced include (a) principal component analysis, (b) dissimilarity measures, (c) T (2)-chart for quality control, and (d) change point analysis. We demonstrate the workflow by a step-by-step assessment of a subset of Study 5 for the Clinical Proteomics Technology Assessment for Cancer (CPTAC) using our R functions.

  3. Targeted pesticide residue analysis using triple Quad LC-MS/MS.

    Science.gov (United States)

    Alder, Lutz

    2011-01-01

    The determination of pesticide residues by HPLC-MS/MS requires decisions on a multitude of analytical parameters. This includes the selection of eluents, columns and ion sources, but also the optimization of the tandem mass spectrometer for the selected target analytes. Another aspect is the use of the restricted acquisition time between two chromatographic data points. An appropriate selection of all these parameters as well as the measures to avoid interference by cross talks and wrong quantitative results by matrix effects is discussed in this chapter.

  4. Validation of an HPLC-MS/MS and Wipe Procedure for Mitomycin C Contamination

    OpenAIRE

    B’Hymer, C.; Connor, T.H.; Stinson, D.; Pretty, J.R.

    2014-01-01

    A high-performance liquid chromatography-tandem mass spectrometric (HPLC-MS/MS) method was developed for the determination of mitomycin C, an anticancer drug, from contamination on various surfaces. Mitomycin C is often used in various forms of intraperitoneal chemotherapy, and operating room healthcare worker exposure to this drug is possible. The surface testing method consisted of a wiping procedure utilizing a solution of 20/45/35 (v/v/v) of acetonitrile-isopropanol-water made 0.01 M in a...

  5. STS-47 MS Davis and MS Jemison conduct LBNP experiment in the SLJ module

    Science.gov (United States)

    1992-01-01

    At the aft end of the Spacelab Japan (SLJ) science module, STS-47 Mission Specialist (MS) N. Jan Davis (foreground) readies Rack 9 Automatic Blood Pressure System (ABPS) controls as MS Mae C. Jemison, inside the cylindrical fabric lower body negative pressure (LBNP) device, waits for the LBNP experiment to begin. LBNP device is sealed around Jemison's waist. It is attached to the SLJ floor and has a controller that operates a pump to change the pressure inside. Davis will monitor Jemison's pulse rate, blood pressure, and cardiac dimensions and functions.

  6. HPLC Fingerprint and LC/MS/MS Identification of the Active Components in Radix Salviae Miltiorrhizae

    Institute of Scientific and Technical Information of China (English)

    HU,Ping; LIANG,Qiong-Lin; LUO,Guo-An; JIANG,Zhi-Hong

    2004-01-01

    @@ Radix Salviae Miltiorrhizae (丹参, RSM), an important Chinese Materia Medica, is widely used for cardiovascular diseases in China. Phenolic compounds[1] and diterpenoids[2] which are the major constituents of RSM have been reported to protect myocardium against ischemia-induced derangement, protect neural cells against injuries caused by anoxia,inhibit platelet aggregation, reduce hepatic fibrosis and depress the activities of HIV-1.[3] For the purposes of establishing quality standard of RSM and studying the relationship between the pharmacological activities and quantities of constituents, we conducted studies on HPLC fingerprint and LC-MS-MS identification of the active constituents of RSM.

  7. Analysis of pesticide residues in strawberries and soils by GC-MS/MS, LC-MS/MS and two-dimensional GC-time-of-flight MS comparing organic and integrated pest management farming.

    Science.gov (United States)

    Fernandes, Virgínia C; Lehotay, Steven J; Geis-Asteggiante, Lucía; Kwon, Hyeyoung; Mol, Hans G J; van der Kamp, Henk; Mateus, Nuno; Domingues, Valentina F; Delerue-Matos, Cristina

    2014-01-01

    This study analysed 22 strawberry and soil samples after their collection over the course of 2 years to compare the residue profiles from organic farming with integrated pest management practices in Portugal. For sample preparation, we used the citrate-buffered version of the quick, easy, cheap, effective, rugged, and safe (QuEChERS) method. We applied three different methods for analysis: (1) 27 pesticides were targeted using LC-MS/MS; (2) 143 were targeted using low pressure GC-tandem mass spectrometry (LP-GC-MS/MS); and (3) more than 600 pesticides were screened in a targeted and untargeted approach using comprehensive, two-dimensional gas chromatography time-of-flight mass spectrometry (GC × GC-TOF-MS). Comparison was made of the analyses using the different methods for the shared samples. The results were similar, thereby providing satisfactory confirmation of both similarly positive and negative findings. No pesticides were found in the organic-farmed samples. In samples from integrated pest management practices, nine pesticides were determined and confirmed to be present, ranging from 2 µg kg(-1) for fluazifop-p-butyl to 50 µg kg(-1) for fenpropathrin. Concentrations of residues in strawberries were less than European maximum residue limits.

  8. The role of GC-MS/MS with triple quadrupole in pesticide residue analysis in food and the environment

    OpenAIRE

    Hernández Hernández, Félix; Cervera Vidal, María Inés; Portolés Nicolau, Tania; Beltrán Arandes, Joaquim; Pitarch Arquimbau, María Elena

    2013-01-01

    Gas chromatography coupled to tandem mass spectrometry (GC-MS/MS) using a triple quadrupole (QqQ) analyzer has in the last few years become a powerful technique for the determination of pesticide residues due to its robustness, and excellent sensitivity and selectivity. This review gives an overview of currently published applications of GC-MS/MS with a QqQ analyzer for pesticide residue analysis of different food and environmental sample matrices. This technique allows the reliable quantific...

  9. Qualitative analysis of catechins from green tea GMB-4 clone using HPLC and LC-MS/MS

    Directory of Open Access Journals (Sweden)

    Erna Susanti

    2015-12-01

    Conclusions: The HPLC and LC-MS/MS methods were successfully tuned for the qualitative analysis of green tea extract with EGCG and ECG. Four major catechins were separated and identified by LC-MS/MS, such as EGCG, epigallocatechin, ECG and epicatechin. The result of HPLC analysis showed that EGCG and ECG were main components from catechins isolation of green tea GMB-4 clone.

  10. ms_lims, a simple yet powerful open source laboratory information management system for MS-driven proteomics.

    Science.gov (United States)

    Helsens, Kenny; Colaert, Niklaas; Barsnes, Harald; Muth, Thilo; Flikka, Kristian; Staes, An; Timmerman, Evy; Wortelkamp, Steffi; Sickmann, Albert; Vandekerckhove, Joël; Gevaert, Kris; Martens, Lennart

    2010-03-01

    MS-based proteomics produces large amounts of mass spectra that require processing, identification and possibly quantification before interpretation can be undertaken. High-throughput studies require automation of these various steps, and management of the data in association with the results obtained. We here present ms_lims (http://genesis.UGent.be/ms_lims), a freely available, open-source system based on a central database to automate data management and processing in MS-driven proteomics analyses.

  11. Robert Carswell: the first illustrator of MS.

    Science.gov (United States)

    Murray, T J

    2009-09-01

    The first illustration of multiple sclerosis (MS) was by a young Scottish physician and artist, Dr Robert Carswell. Recognized as a talented illustrator by his teachers, he was encouraged to create an anatomy and pathology atlas. He spent years in the hospitals and mortuaries of Paris and Lyon painting watercolours and pen and ink drawings of patients and post mortem preparations. Of the 1034 paintings, 99 are of the brain and spinal cord and Plate 4, figure 4.4 in the atlas (Figure 2), is of MS. Carswell indicated he saw two examples of this pathology, but had not examined either patient, but illustrated one of them. We know little about the clinical history other than that the patient was paralyzed. About 200 of the atlases were printed, and it is still regarded as one of the greatest and most beautiful of all medical books. Carswell was appointed as the first Professor of Anatomy at the North London Hospital, later renamed the University College Hospital UK, where the original copy of his great atlas is archived. Due to ill health he resigned after a few years to reside in the healthier air outside Brussels, Belgium. He was appointed physician to King Leopold, but was also noted for his care of the poor. Queen Victoria knighted him for his care of King Louis Philippe of France when he was in exile. Although English journals did not note his passing at the age of 64 years, his great atlas remains as his memorial.

  12. VOC identification and inter-comparison from laboratory biomass burning using PTR-MS and PIT-MS

    Science.gov (United States)

    C. Warneke; J. M. Roberts; P. Veres; J. Gilman; W. C. Kuster; I. Burling; R. Yokelson; J. A. de Gouw

    2011-01-01

    Volatile organic compounds (VOCs) emitted from fires of biomass commonly found in the southeast and southwest U.S. were investigated with PTR-MS and PIT-MS, which are capable of fast measurements of a large number of VOCs. Both instruments were calibrated with gas standards and mass dependent calibration curves are determined. The sensitivity of the PIT-MS linearly...

  13. HPLC-MS/MS shotgun proteomic research of deer antlers with multiparallel protein extraction methods.

    Science.gov (United States)

    Gao, Liang; Tao, Dingyin; Shan, Yichu; Liang, Zhen; Zhang, Lihua; Huo, Yushu; Zhang, Yukui

    2010-12-15

    Deer antlers mature rapidly in 60 days, and subsequently shed in 5 days with rapid ossification. During this procedure, the function of deer antlers changes significantly. Therefore, the profiling of antler proteome is helpful to discover important growing and shedding regulation proteins, which might be of great significance for studying development and regeneration. In this study, a parallel protein extraction strategy was developed to extract proteins from antlers of red deer with five different lysis solutions, followed by shotgun proteomic analysis by microflow reversed-phase liquid chromatography/electrospray ionization/tandem mass spectrometry (μRPLC-ESI-MS/MS) with a 30 cm-long serially coupled microcolumn. Our experimental results showed that the identified proteins extracted by five kinds of lysis solution were complementary to each other. In total, 416 unique proteins were identified, with relative molecular masses from 2000 to 600,000, and isoelectric points from 3.84 to 11.57. All these results demonstrate that the combination of parallel protein extraction strategy and μRPLC-ESI-MS/MS analysis with serially coupled long microcolumns might be of great significance for comprehensive proteomic research of deer antler.

  14. Determination of Dextromethorphan in Oral Fluid by LC-MS-MS.

    Science.gov (United States)

    Amaratunga, Piyadarsha; Clothier, Morgan; Lorenz Lemberg, Bridget; Lemberg, Dave

    2016-06-01

    Dextromethorphan (DXM) is an antitussive drug found in commonly used nonprescription cold and cough medications. At low doses, DXM is a safe drug that does not produce adverse reactions. However, abuse of DXM has been reported among adolescents and young adults using the drug at higher doses. DXM is not a scheduled drug in the USA, and the primary reason for its abuse is the ease of availability. DXM is available to purchase in the form of over-the-counter cough medications, such as Robitussin(®) and Coricidin(®), or it can be purchased over the Internet in the form of a powder. In this research work, we developed an LC-MS-MS method that can quantify DXM and dextrorphan (DXO) in oral fluid in a high-throughput toxicology laboratory setting. The developed method was validated according to the Scientific Working Group for Forensic Toxicology guidelines. The linear dynamic range was 5-100 ng/mL with a lowest limit of quantitation (LLOQ) of 5.0 ng/mL for DXM and DXO. Overall, the results of the accuracy and the precision values were within the acceptance criteria for both drugs. In addition, selectivity, matrix effect and recovery were calculated for the LC-MS-MS method. Authentic samples (n = 59) were tested to evaluate the applicability of the method. Thirty samples were found to be positive for DXM and DXO and two samples were found to be positive for DXM only.

  15. [Simultaneous determination of adrenaline, noradrenaline, cortisone and cortisol in plasma with HPLC/MS/MS].

    Science.gov (United States)

    Yong, Li; Wang, Yu; Zou, Xiao-Li; Zhu, Lan; Xie, Hui-Ru; Li, Long-Jiang

    2014-01-01

    To develop a method for simultaneous determination of adrenaline, noradrenaline, cortisone and cortisol in plasma using HPLC/MS/MS. Sample proteins were precipitated with acetonitrile and the sample solution was injected into HPLC/MS/MS after centrifugation at 15,000 r/min for 5 min. Electrospray ionization (ESI) and the positive ion detection were applied with a multiple reaction monitoring (MRM) mode for quantitative analyses. Under the optimal conditions, good linearity (r > 0.999) was observed in the range of 0.02-200.00 ng/mL of target compounds. The detection limit reached 4.13 pg/mL, 4.64 pg/mL, 4.29 pg/mL and 4.52 pg/mL for adrenaline, noradrenaline, cortisone and cortisol respectively. The inter-day and intra-day precisions ranged from 1.19%-5.42% and 2.16%-6.04% respectively. Satisfied results were achieved using human plasma samples, with a spiked recovery in the range of 80.0%-109.0% and a relative standard deviation of 3.93%-7.57%. The proposed method is quick, sensitive and suitable for batch analyses of plasma samples.

  16. Automated saliva processing for LC-MS/MS: Improving laboratory efficiency in cortisol and cortisone testing.

    Science.gov (United States)

    Antonelli, Giorgia; Padoan, Andrea; Artusi, Carlo; Marinova, Mariela; Zaninotto, Martina; Plebani, Mario

    2016-04-01

    The aim of this study was to implement in our routine practice an automated saliva preparation protocol for quantification of cortisol (F) and cortisone (E) by LC-MS/MS using a liquid handling platform, maintaining the previously defined reference intervals with the manual preparation. Addition of internal standard solution to saliva samples and calibrators and SPE on μ-elution 96-well plate were performed by liquid handling platform. After extraction, the eluates were submitted to LC-MS/MS analysis. The manual steps within the entire process were to transfer saliva samples in suitable tubes, to put the cap mat and transfer of the collection plate to the LC auto sampler. Transference of the reference intervals from the manual to the automated procedure was established by Passing Bablok regression on 120 saliva samples analyzed simultaneously with the two procedures. Calibration curves were linear throughout the selected ranges. The imprecision ranged from 2 to 10%, with recoveries from 95 to 116%. Passing Bablok regression demonstrated no significant bias. The liquid handling platform translates the manual steps into automated operations allowing for saving hands-on time, while maintaining assay reproducibility and ensuring reliability of results, making it implementable in our routine with the previous established reference intervals. Copyright © 2015 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

  17. Direct injection HILIC-MS/MS analysis of darunavir in rat plasma applying supported liquid extraction

    Institute of Scientific and Technical Information of China (English)

    Bokka Ramesh; Nemali Manjula; Sistla Ramakrishna; Potturi Sita Devi

    2015-01-01

    A novel bioanalytical method was developed and validated for the quantitative determination of darunavir (DRV) in rat plasma by employing hydrophilic interaction chromatography and tandem mass spectrometry (HILIC–MS/MS) with supported liquid extraction (SLE). Irbesartan (IRB) was used as an internal standard (IS). The analyte in rat plasma (200 mL) was isolated through SLE using ethyl acetate as the eluting solvent. The chromatographic separation was achieved on Luna-HILIC (250 mm4.6 mm, 5 μm) column with a mobile phase of 0.1% of formic acid in water:acetonitrile (5: 95, v/v), at a constant flow rate of 1.0 mL/min. The MS/MS ion transitions for DRV (548.1-392.0) and IS (429.2-207.1) were monitored on an ion trap mass spectrometer, operating in the multiple reaction monitoring (MRM) mode. The lower limit of quantitation (LLOQ) was 0.2 ng/mL and quantitation range was 0.2–5000 ng/mL. The method was validated for its selectivity, sensitivity, carryover, linearity, precision, accuracy, recovery, matrix effect and stability. The method was successfully applied to pharmacokinetic study in rats.

  18. Rapid analysis of Listeria monocytogenes cell wall teichoic acid carbohydrates by ESI-MS/MS.

    Science.gov (United States)

    Eugster, Marcel R; Loessner, Martin J

    2011-01-01

    We report the application of electrospray ionization (ESI) mass spectrometry for compositional characterization of wall teichoic acids (WTA), a major component of gram-positive bacterial cell walls. Tandem mass spectrometry (ESI-MS/MS) of purified and chemically hydrolyzed monomeric WTA components provided sufficient information to identify WTA monomers and their specific carbohydrate constituents. A lithium matrix was used for ionization of uncharged WTA monomers, and successfully applied to analyze the WTA molecules of four Listeria strains differing in carbohydrate substitution on a conserved polyribitol-phosphate backbone structure. Carbohydrate residues such as N-acetylglucosamine or rhamnose linked to the WTA could directly be identified by ESI-MS/MS, circumventing the need for quantitative analysis by gas chromatography. The presence of a terminal N-acetylglucosamine residue tethered to the ribitol was confirmed using fluorescently labeled wheat-germ agglutinin. In conclusion, the mass spectrometry method described here will greatly facilitate compositional analysis and characterization of teichoic acids and similar macromolecules from diverse bacterial species, and represents a significant advance in the identification of serovar-specific carbohydrates and sugar molecules on bacteria.

  19. Rapid analysis of Listeria monocytogenes cell wall teichoic acid carbohydrates by ESI-MS/MS.

    Directory of Open Access Journals (Sweden)

    Marcel R Eugster

    Full Text Available We report the application of electrospray ionization (ESI mass spectrometry for compositional characterization of wall teichoic acids (WTA, a major component of gram-positive bacterial cell walls. Tandem mass spectrometry (ESI-MS/MS of purified and chemically hydrolyzed monomeric WTA components provided sufficient information to identify WTA monomers and their specific carbohydrate constituents. A lithium matrix was used for ionization of uncharged WTA monomers, and successfully applied to analyze the WTA molecules of four Listeria strains differing in carbohydrate substitution on a conserved polyribitol-phosphate backbone structure. Carbohydrate residues such as N-acetylglucosamine or rhamnose linked to the WTA could directly be identified by ESI-MS/MS, circumventing the need for quantitative analysis by gas chromatography. The presence of a terminal N-acetylglucosamine residue tethered to the ribitol was confirmed using fluorescently labeled wheat-germ agglutinin. In conclusion, the mass spectrometry method described here will greatly facilitate compositional analysis and characterization of teichoic acids and similar macromolecules from diverse bacterial species, and represents a significant advance in the identification of serovar-specific carbohydrates and sugar molecules on bacteria.

  20. MALDI MSI and LC-MS/MS: Towards preclinical determination of the neurotoxic potential of fluoroquinolones.

    Science.gov (United States)

    Shobo, Adeola; Baijnath, Sooraj; Bratkowska, Dominika; Naiker, Suhashni; Somboro, Anou M; Bester, Linda A; Singh, Sanil D; Naicker, Tricia; Kruger, Hendrik G; Govender, Thavendran

    2016-08-01

    Fluoroquinolones are broad-spectrum antibiotics with efficacy against a wide range of pathogenic microbes associated with respiratory and meningeal infections. The potential toxicity of this class of chemical agents is a source of major concern and is becoming a global issue. The aim of this study was to develop a method for the brain distribution and the pharmacokinetic profile of gatifloxacin in healthy Sprague-Dawley rats, via Multicenter matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI MSI) and quantitative liquid chromatography-tandem mass spectrometry (LC-MS/MS). We developed a sensitive LC-MS/MS method to quantify gatifloxacin in plasma, lung, and brain homogenates. A pharmacokinetic profile was observed where there is a double peak pattern; a sharp initial increase in the concentration soon after dosing followed by a steady decline until another increase in concentration after a longer period post dosing in all three biological samples was observed. The imaging results showed the drug gradually entering the brain via the blood brain barrier and into the cortical regions from 15 to 240 min post dose. As time elapses, the drug leaves the brain following the same path as it followed on its entry and finally concentrates at the cortex. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.

  1. LC-MS/MS Validation Analysis of Trastuzumab Using dSIL Approach for Evaluating Pharmacokinetics

    Directory of Open Access Journals (Sweden)

    Rohit H. Budhraja

    2016-11-01

    Full Text Available Quantitative targeted proteomics based approaches deploy state-of-the-art Liquid chromatography tandem mass spectrometry LC-MS technologies and are evolving as a complementary technique to standard ligand-binding based assays. Advancements in MS technology, which have augmented the specificity, selectivity and sensitivity limits of detection and freedom from antibody generation, have made it amicable towards various clinical applications. In our current work, a surrogate peptide based quantitative proteomics assessment is performed by selecting specific signature peptides from the complementary determining region CDR region of trastuzumab (Herclon®, Roche products in India. We developed a double Stable Isotope Label (dSIL approach by using two different surrogate peptides to evaluate the proteolytic digestion efficiency and accurate quantification of the target analyte peptide of Herclon® in human serum. Method validation experiments were meticulously performed as per bioanalytical method validation guidelines. The dSIL approach, using an LC-MS/MS based quantification assay demonstrated good linearity over a range of 5–500 µg/mL of Herclon®, and validation experimental data is in compliance with bioanalytical regulatory guidelines.

  2. Detection of β-methylphenethylamine, a novel doping substance, by means of UPLC/MS/MS.

    Science.gov (United States)

    Chołbiński, Piotr; Wicka, Mariola; Kowalczyk, Katarzyna; Jarek, Anna; Kaliszewski, Paweł; Pokrywka, Andrzej; Bulska, Ewa; Kwiatkowska, Dorota

    2014-06-01

    Novel substances of expected doping activity are constantly introduced to the market. β-Methylphenethylamine (BMPEA) is classified as a doping agent by the World Anti-Doping Agency as it is a positional isomer of amphetamine. In this work, the development and application of a simple and rapid analytical procedure that enables discrimination between both isomers is described. The analytes of interest were extracted from urine by a two-step liquid-liquid extraction and then analyzed by UPLC/MS/MS under isocratic conditions. The entire analytical procedure was validated by evaluating its selectivity, discrimination capabilities, carry-over, sensitivity, and influence of matrix effects on its performance. Application of the method resulted in detection of BMPEA in eight anti-doping samples, including the first report of adverse analytical finding regarding its use. Further analysis showed that BMPEA may be eliminated unchanged along with its phase II conjugates, the hydrolysis of which may considerably improve detection capabilities of the method. Omission of the hydrolysis step may therefore, produce false-negative results. Testing laboratories should also carefully examine their LC/MS/MS-based amphetamine and BMPEA findings as both isomers fragment yielding comparable collision-induced dissociation spectra and their insufficient chromatographic separation may result in misidentification. This is of great importance in case of forensic analyses as BMPEA is not controlled by the public law, and its manufacturing, distribution, and use are legal.

  3. UP-HILIC-MS/MS to Determine the Action Pattern of Penicillium sp. Dextranase

    Science.gov (United States)

    Yi, Lin; Sun, Xue; Du, Kenze; Ouyang, Yilan; Wu, Chengling; Xu, Naiyu; Linhardt, Robert J.; Zhang, Zhenqing

    2015-07-01

    Investigation of the action pattern of enzymes acting on carbohydrates is challenging, as both the substrate and the digestion products are complex mixtures. Dextran and its enzyme-derived oligosaccharides are widely used for many industrial applications. In this work, a new method relying on ultra-performance hydrophilic interaction liquid chromatography quadrupole time-of-flight tandem mass spectrometry (UP-HILIC- Q/TOF-MS/MS) was developed to analyze a complex mixture of dextran oligosaccharide products to determine the action pattern of dextranase. No derivatization of oligosaccharides was required and the impact of the α- and β-configurations of the native oligosaccharides on the chromatographic separation was eliminated. The 1→6, 1→3, 1→4 backbone linkages and the branch linkages of these oligosaccharides were all distinguished from diagnostic ions in their MS/MS spectra, including fragments corresponding to 0,2A, 0,3A, 0,4A, B-H2O, 2,5A, and 3,5A. The sequences of the oligosaccharide products were similarly established. Thus, the complex oligosaccharide mixtures in dextran digestion products were profiled and identified using this method. The more enzyme-resistant structures in dextran were established using much less sample, labor, time, and uncertainty than in previous studies. This method provides an efficient, sensitive, and straightforward way to monitor the entire process of digestion, establish the action pattern of the dextranase from Penicillium sp., and to support the proper industrial application of dextranase.

  4. Analytical Method Details (MS): SE50_MS01 [Metabolonote[Archive

    Lifescience Database Archive (English)

    Full Text Available 12.1 min, and 99.5% A/0.5% B at 15.0 min; flow rate, 0.3 ml min-1; column temperature, 40°C. For MS: capil...lary voltage, +3.0 keV, cone voltage, 25.0 V; source temperature, 120°C; desolvatio

  5. [LC-MS/MS analysis of determination of strychnine and brucine in formaldehyde fixed tissue].

    Science.gov (United States)

    Zhan, Lan-fen; Liu, Ming-dong; Yan, You-yi; Ye, Yi; Wang, Wei; Wang, Zhi-hui; Zhao, Jun-hong; Liao, Lin-chuan

    2012-10-01

    To establish a method for determination of strychnine and brucine in formaldehyde fixed tissue by LC-MS/MS analysis. The samples were pretreated with solid phase extraction using SCX cartridges and separated on SB-C18 column with mobile phase 0.1% formic acid : 0.1% formic acid-acetonitrile (75:25). Electrospray ionization (ESI) source was utilized and operated in positive ion mode. Multiple reactions monitoring (MRM) mode was applied. External standard method was applied for quantitation. The chromatographic separation of strychnine and brucine in formaldehyde fixed nephritic and hepatic tissues resulted successfully. The standard curve was linear in the range of 0.002-2.0 microg/g for strychnine and brucine in formaldehyde fixed tissues, and the correlation coefficient was more than 0.996. The limits of detection (LOD) of strychnine and brucine in nephritic tissues were 0.06ng/g and 0.03 ng/g, respectively. The LOD of both chemicals were 0.3 ng/g in hepatic tissues. The extraction recovery rate was more than 74.5%. The precision of intra-day and inter-day were both less than 8.2%. Strychnine and brucine can be sensitive to be determined in formaldehyde fixed tissue by LC-MS/MS analysis. It can be applied in the forensic toxicological analysis.

  6. LC-MS/MS Identification of a Bromelain Peptide Biomarker from Ananas comosus Merr

    Directory of Open Access Journals (Sweden)

    Eric R. Secor

    2012-01-01

    Full Text Available Bromelain (Br is a cysteine peptidase (GenBank AEH26024.1 from pineapple, with over 40 years of clinical use. The constituents mediating its anti-inflammatory activity are not thoroughly characterized and no peptide biomarker exists. Our objective is to characterize Br raw material and identify peptides in the plasma of Br treated mice. After SDS-PAGE in-gel digestion, Br (VN#3507; Middletown, CT, USA peptides were analyzed via LC/MS/MS using 95% protein probability, 95% peptide probability, and a minimum peptide number = 5. Br spiked mouse plasma (1 ug/ul and plasma from i.p. treated mice (12 mg/kg were assessed using SRM. In Br raw material, we identified seven proteins: four proteases, one jacalin-like lectin, and two protease inhibitors. In Br spiked mouse plasma, six proteins (ananain, bromelain inhibitor, cysteine proteinase AN11, FB1035 precursor, FBSB precursor, and jacalin-like lectin were identified. Using LC/MS/MS, we identified the unique peptide, DYGAVNEVK, derived from FB1035, in the plasma of i.p. Br treated mice. The spectral count of this peptide peaked at 6 hrs and was undetectable by 24 hrs. In this study, a novel Br peptide was identified in the plasma of treated mice for the first time. This Br peptide could serve as a biomarker to standardize the therapeutic dose and maximize clinical utility.

  7. Application of LC-MS/MS MRM to Determine Staphylococcal Enterotoxins (SEB and SEA) in Milk.

    Science.gov (United States)

    Andjelkovic, Mirjana; Tsilia, Varvara; Rajkovic, Andreja; De Cremer, Koen; Van Loco, Joris

    2016-04-20

    Staphylococcus aureus is one of the important aetiological agents of food intoxications in Europe and can cause gastro-enteritis through the production of various staphylococcal enterotoxins (SEs) in foods. Due to their stability and ease of production and dissemination, some SEs have also been studied as potential agents for bioterrorism. Therefore, specific and accurate analytical tools are required to detect and quantify SEs. Online solid-phase extraction liquid chromatography electrospray ionization tandem mass spectrometry (online SPE-LC-ESI-MS/MS) based on multiple reaction monitoring (MRM) was used to detect and quantify two types of SE (A and B) spiked in milk and buffer solution. SE extraction and concentration was performed according to the European Screening Method developed by the European Reference Laboratory for Coagulase Positive Staphylococci. Trypsin digests were screened for the presence of SEs using selected proteotypic heavy-labeled peptides as internal standards. SEA and SEB were successfully detected in milk samples using LC-MS/MS in MRM mode. The selected SE peptides were proteotypic for each toxin, allowing the discrimination of SEA and SEB in a single run. The detection limit of SEA and SEB was approximately 8 and 4 ng/g, respectively.

  8. Analysis of six relevant toxaphene congeners in biological samples using ion trap MS/MS.

    Science.gov (United States)

    Gouteux, Bruno; Lebeuf, Michel; Trottier, Steve; Gagné, Jean-Pierre

    2002-10-01

    The quantification of six polychlorinated bornanes (CHBs) was studied using ion trap MS/MS. The significance of the selection of parent ions (Ip) and daughter ions (Id) on the detection of these toxaphene congeners was assessed in standard solution and biological samples. Our results indicate that different Ip and Id, selected at either low or high mass-to-charge (m/z) ratios, influence drastically the response factor of the CHBs and the chemical noise observed. For the octachlorinated toxaphene congeners (Parlar-26 (P-26), Parlar-40/41 (P-40/41), Parlar-44 (P-44)), the detection performance of the ion trap MS/MS is similar whether Ip and Id were chosen at low or high m/z ratios. However, the selection of Ip and Id at high m/z ratios clearly enhances the detection of the nonachlorinated toxaphene congeners (Parlar-50 (P-50), Parlar-62 (P-62)). The improved method, which selects Ip and Id at low m/z ratios for P-26, P-40/41 and P-44 and at high m/z ratios for P-50 and P-62, permitted to obtain low detection limits as well as repeatable and accurate results.

  9. Annotation of Different Dehydrocatechin Oligomers by MS/MS and Their Occurrence in Black Tea

    NARCIS (Netherlands)

    Verloop, Annewieke J.W.; Gruppen, Harry; Vincken, Jean Paul

    2016-01-01

    Dehydrocatechins (DhC's), oligomeric oxidation products of (epi)catechins, were formed in model incubations of epicatechin with mushroom tyrosinase. DhC oligomers up to tetramers were detected by reversed-phase ultrahigh-performance liquid chromatography mass spectrometry (RP-UHPLC-MS) analysis.

  10. [Simultaneous determination of gestodene, etonogestrel and ethinylestradiol in plasma by LC-MS/MS following derivatization].

    Science.gov (United States)

    Liu, Xiao-Fen; Ding, Cun-Gang; Ge, Qing-Hua; Zhou, Zhen; Zhi, Xiao-Jin

    2010-01-01

    To establish a sensitive and specific method for simultaneous determination of gestodene, etonogestrel and ethinylestradiol in plasma by LC-MS/MS, plasma samples were extracted and derivatized before injection. An ESI ion source was used and operated in the positive ion mode with multiple reaction monitoring (MRM). Norgestrel was chosen as internal standard and performed on a C18 (100 mm x 2.1 mm, 5 microm) column. The concentrations of gestodene, etonogestrel and ethinylestradiol were measured, using step-gradient mobile phase and step-gradient flow rate. The method was validated over the concentration range of 0.1-20 ng x mL(-1) for gestodene and etonogestrel and 0.01-2 ng x mL(-1) for ethinylestradiol, and showed excellent linearity. The intra- and inter-assay accuracy and precision were below 10.0% and recovery was 93.6%-110.9% over the three concentration levels evaluated. The method was applied in pharmacokinetic study of the compound gestodene patch and the compound etonogestrel patch in rabbits. The LC-MS/MS method was selective, accurate and sensitive, especially the LOQ were 100 pg x mL(-1) for gestodene and etonogestrel and 10 pg x mL(-1) for ethinylestradiol. The method was successfully applied in pharmacokinetic study for contraceptives.

  11. LC-MS/MS Identification of a Bromelain Peptide Biomarker from Ananas comosus Merr.

    Science.gov (United States)

    Secor, Eric R; Szczepanek, Steven M; Singh, Anurag; Guernsey, Linda; Natarajan, Prabitha; Rezaul, Karim; Han, David K; Thrall, Roger S; Silbart, Lawrence K

    2012-01-01

    Bromelain (Br) is a cysteine peptidase (GenBank AEH26024.1) from pineapple, with over 40 years of clinical use. The constituents mediating its anti-inflammatory activity are not thoroughly characterized and no peptide biomarker exists. Our objective is to characterize Br raw material and identify peptides in the plasma of Br treated mice. After SDS-PAGE in-gel digestion, Br (VN#3507; Middletown, CT, USA) peptides were analyzed via LC/MS/MS using 95% protein probability, 95% peptide probability, and a minimum peptide number = 5. Br spiked mouse plasma (1 ug/ul) and plasma from i.p. treated mice (12 mg/kg) were assessed using SRM. In Br raw material, we identified seven proteins: four proteases, one jacalin-like lectin, and two protease inhibitors. In Br spiked mouse plasma, six proteins (ananain, bromelain inhibitor, cysteine proteinase AN11, FB1035 precursor, FBSB precursor, and jacalin-like lectin) were identified. Using LC/MS/MS, we identified the unique peptide, DYGAVNEVK, derived from FB1035, in the plasma of i.p. Br treated mice. The spectral count of this peptide peaked at 6 hrs and was undetectable by 24 hrs. In this study, a novel Br peptide was identified in the plasma of treated mice for the first time. This Br peptide could serve as a biomarker to standardize the therapeutic dose and maximize clinical utility.

  12. Quality Evaluation and Regional Analysis of Psoraleae Fructus by HPLC-DAD-MS/MS plus Chemometrics

    Institute of Scientific and Technical Information of China (English)

    YAN Dong-mei; CHANG Yan-xu; KANG Li-yuan; GAO Xiu-mei

    2010-01-01

    Objective To evaluate the quality of Psoralea corylifolia collected from 12 provinces of China.Methods An HPLCDAD-MS/MS method was used to identify,determine,and estimate 14 representative bioactive compounds in P.corylifolia.Then on the basis of the content data,the chemometrics method was used to differentiate 20 samples from different regions.Results The quality of P.corylifolia from 12 different provinces of China was evaluated by this method.Though the samples showed similar profiles,content of the detected markers varied significantly in different regions and batches.According to the results of the hierarchical cluster analysis and principle component analysis,it can be concluded that the samples from different origins could be clustered reasonably into two groups,as well as successfully distinguished.Conclusion A simple and reliable new method which used HPLC-DAD-MS/MS and chemometrics has been developed to characterize,classify,and control the quality of P.corylifolia.

  13. Annotation of Different Dehydrocatechin Oligomers by MS/MS and Their Occurrence in Black Tea

    NARCIS (Netherlands)

    Verloop, Annewieke J.W.; Gruppen, Harry; Vincken, Jean Paul

    2016-01-01

    Dehydrocatechins (DhC's), oligomeric oxidation products of (epi)catechins, were formed in model incubations of epicatechin with mushroom tyrosinase. DhC oligomers up to tetramers were detected by reversed-phase ultrahigh-performance liquid chromatography mass spectrometry (RP-UHPLC-MS) analysis.

  14. metaMS: An open-source pipeline for GC–MS-based untargeted metabolomics

    NARCIS (Netherlands)

    Wehrens, H.R.M.J.; Weingart, G.; Mattivi, F.

    2014-01-01

    Untargeted metabolomics are rapidly becoming an important tool for studying complex biological samples. Gas chromatography–mass spectrometry (GC–MS) is the most widely used analytical technology for metabolomic analysis of compounds that are volatile or can be chemically derivatised into volatile co

  15. Determination of N-nitrosodiethanolamine in cosmetic products by LC-MS-MS.

    Science.gov (United States)

    Schothorst, R C; Somers, H H J

    2005-02-01

    We have developed and validated in-house a liquid chromatography and mass spectrometry (LC-MS-MS) method for determination of N-nitrosodiethanolamine (NDELA) in cosmetics. The sample is diluted with water and then a C18 clean-up is performed. The average recovery of NDELA is 88.3%, range 48.3-112.7%, and the limit of detection is 22.8 microg kg-1. The repeatability is 7.6%, and the intermediate precision is 8.7%. Surveys were carried out in the Netherlands in September and October 2002 to determine the quantities of NDELA in cosmetics marketed in the Netherlands. The LC-MS-MS method was used to determine the NDELA content of 140 cosmetic products including shower gels, hair oils, shampoos and conditioners, cream and foam baths, mud baths, scrubs, creme and other soaps, and body washes. NDELA at levels ranging from 23 to 992 microg kg-1 was found in 35 cosmetic products.

  16. Photocatalytic degradation of hexazinone and its determination in water via UPLC-MS/MS.

    Science.gov (United States)

    Mei, Mei; Du, Zhenxia; Xu, Ruifen; Chen, Yun; Zhang, Haojie; Qu, Shuping

    2012-06-30

    Degradation of hexazinone has been investigated by means of photocatalysis of mixed-phase crystal nano-TiO(2). Influences of adsorption, amount of nano-TiO(2), pH and irradiation time on the photocatalytic process are studied. Results show that hexazinone is totally degraded within 40min of irradiation under pH neutral conditions. This compares favorably with Degussa P25 TiO(2) when conducted under the same experimental conditions. Preliminary photocatalytic kinetic information for hexazinone degradation is proposed. First order kinetics is obtained for the adsorption and photocatalytic degradation reactions, which fit the Langmuir-Hinshelwood model. A rapid, sensitive and accurate UPLC-MS/MS technique is developed and utilized to determine the level of hexazinone in water in support of the degradation kinetics study. The results indicate a limit of detection (LOD) at 0.05μg/l and the recoveries between 90.2 and 98.5% with relative standard deviations (RSD) lower than 12%. A LC-MS/MS technique is used to trace the degradation process. Complete degradation is achieved into final products including nontoxic water, carbon dioxide and urea. A probable pathway for the total photocatalytic degradation of hexazinone is proposed.

  17. Potential Health Benefits and Metabolomics of Camel Milk by GC-MS and ICP-MS.

    Science.gov (United States)

    Ahamad, Syed Rizwan; Raish, Mohammad; Ahmad, Ajaz; Shakeel, Faiyaz

    2017-02-01

    None of the research reports reveals the metabolomics and elemental studies on camel milk. Recent studies showed that camel milk possesses anticancer and anti-inflammatory activity. Metabolomics and elemental studies were carried out in camel milk which showed us the pathways and composition that are responsible for the key biological role of camel milk. Camel milk was dissolved in methanol and chloroform fraction and then vortexed and centrifuged. Both the fractions were derivatized by N,O-bis-(trimethylsilyl)trifluoroacetamide (BSTFA) and TMCS after nitrogen purging and analyzed by GC-MS. Camel milk was also analyzed by ICP-MS after microwave digestion. We found that higher alkanes and fatty acids are present in the chloroform fraction and amino acids, sugars and fatty acid derivatives are present in aqueous fractions. All the heavy metals like As, Pb, Cd, Co, Cu, and Ni were in the safe limits in terms of maximum daily intake of these elements. Na, K, Mg, and Ca were also present in the safe limits in terms of maximum daily intake of these elements. These results suggested that the camel milk drinking is safe and there is no health hazard. The present data of GC-MS and ICP-MS correlate the activities related to camel milk.

  18. Simultaneous Determination of 11 Illicit Phenethylamines in Hair by LC-MS-MS: In Vivo Application.

    Science.gov (United States)

    Nieddu, Maria; Burrai, Lucia; Demontis, Maria Piera; Varoni, Maria Vittoria; Baralla, Elena; Trignano, Claudia; Boatto, Gianpiero

    2015-09-01

    Existing phenethylamines are a class of synthetic compounds that differ from each other only in small changes to a largely conserved chemical structure. The recreational and illicit use of phenethylamines is a widespread problem. A simple procedure for the simultaneous quantitative determination in hair of 11 phenethylamines that are officially recognized as illicit by Italian legislation (p-methoxyamphetamine; p-methoxymethamphetamine; 3,4,5-trimethoxyamphetamine; 2,5-dimethoxyamphetamine; 2,5-dimethoxy-4-methylamphetamine; 2,5-dimethoxy-4-ethylamphetamine; 2,5-dimethoxy-4-bromoamphetamine; 2,5-dimethoxy-4-bromophenethylamine; 2,5-dimethoxy-4-iodophenethylamine; 2,5-dimethoxy-4-ethylthiophenethylamine and 2,5-dimethoxy-4-n-propylthiophenethylamine) has been developed and validated. Extraction from the matrix was performed after incubation in methanolic HCl and filtered reconstituted extracts were injected into a liquid chromatography/tandem mass spectrometry system (LC-MS-MS) without any further purification steps. This validated LC-MS-MS method has been used to determine the in vivo accumulation/retention of the above target analytes in hair after repeat oral administration to rats. This experiment further permitted investigation of the effect of pigmentation on the uptake of these phenethylamines by hair and the effect of hair pigmentation. The developed method could potentially be used for forensic and toxicological purposes, in the detection and quantitation of these illicit substances in human hair in workplace drug testing; drug-facilitated crime investigation; driver re-licensing; determining drug abuse history and postmortem toxicology.

  19. Multimycotoxin UPLC-MS/MS for tea, herbal infusions and the derived drinkable products.

    Science.gov (United States)

    Monbaliu, Sofie; Wu, Aibo; Zhang, Dabing; Van Peteghem, Carlos; De Saeger, Sarah

    2010-12-22

    In recent years the consumption of tea and herbal infusions has increased. These hot drinks are consumed as daily drinks as well as for medicinal purposes. All tea varieties (white, yellow, green, oolong, black and puerh) originate from the leaves of the tea plant, Camellia sinensis. All extracts made of plant or herbal materials which do not contain Camellia sinensis are referred as herbal infusions or tisanes. During processing and manufacturing fungal contamination of the plant materials is possible, enabling contamination of these products with mycotoxins. In this study a multimycotoxin UPLC-MS/MS method was developed and validated for the analysis of the raw tea and herbal infusion materials as well as for their drinkable products. The samples were analyzed by ultra-high-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS), with a mobile phase consisting of variable mixtures of water and methanol with 0.3% formic acid. The limits of detection for the different mycotoxins varied between 2.1 μg/kg and 121 μg/kg for raw materials and between 0.4 μg/L and 46 μg/L for drinkable products. Afterward 91 different tea and herbal infusion samples were analyzed. Only in one sample, Ceylon melange, 76 μg/kg fumonisin B(1) was detected. No mycotoxins were detected in the drinkable products.

  20. Detection and validated quantification of toxic alkaloids in human blood plasma--comparison of LC-APCI-MS with LC-ESI-MS/MS.

    Science.gov (United States)

    Beyer, Jochen; Peters, Frank T; Kraemer, Thomas; Maurer, Hans H

    2007-05-01

    Poisonings with toxic plants may occur after abuse, intentional or accidental ingestion of plants. For diagnosis of such poisonings, multianalyte procedures were developed for detection and validated quantification of the toxic alkaloids aconitine, atropine, colchicine, coniine, cytisine, nicotine and its metabolite cotinine, physostigmine, and scopolamine in plasma using LC-APCI-MS and LC-ESI-MS/MS. After mixed-mode solid-phase extraction of 1 ml of plasma, the analytes were separated using a C8 base select separation column and gradient elution (acetonitrile/ammonium formate, pH 3.5). Calibration curves were used for quantification with cotinine-d(3), benzoylecgonine-d(3), and trimipramine-d(3) as internal standards. The method was validated according to international guidelines. Both assays were selective for the tested compounds. No instability was observed after repeated freezing and thawing or in processed samples. The assays were linear for coniine, cytisine, nicotine and its metabolite cotinine, from 50 to 1000 ng/ml using LC-APCI-MS and 1 to 1000 ng/ml using LC-ESI-MS/MS, respectively, and for aconitine, atropine, colchicine, physostigmine, and scopolamine from 5 to 100 ng/ml for LC-APCI-MS and 0.1 to 100 ng/ml for LC-ESI-MS/MS, respectively. Accuracy ranged from -38.6 to 14.0%, repeatability from 2.5 to 13.5%, and intermediate precision from 4.8 to 13.5% using LC-APCI-MS and from -38.3 to 8.3% for accuracy, from 3.5 to 13.8%, for repeatability, and from 4.3 to 14.7% for intermediate precision using LC-ESI-MS/MS. The lower limit of quantification was fixed at the lowest calibrator in the linearity experiments. With the exception of the greater sensitivity and higher identification power, LC-ESI-MS/MS had no major advantages over LC-APCI-MS. Both presented assays were applicable for sensitive detection of all studied analytes and for accurate and precise quantification, with the exception of the rather volatile nicotine. The applicability of the assays was

  1. Study of the performance of three LC-MS/MS platforms for analysis of perfluorinated compounds

    Energy Technology Data Exchange (ETDEWEB)

    Llorca, Marta; Farre, Marinella [IDAEA-CSIC, Department of Environmental Chemistry, Barcelona (Spain); Pico, Yolanda [Universitat de Valencia, Laboratori de Nutricio i Bromatologia, Facultat de Farmacia, Burjassot, Valencia (Spain); Barcelo, Damia [IDAEA-CSIC, Department of Environmental Chemistry, Barcelona (Spain); King Saud University, Riyadh (Saudi Arabia)

    2010-10-15

    The analytical suitabilities of three different liquid chromatography-tandem mass spectrometry (LC-MS/MS) systems, (1) triple quadrupole (QqQ), (2) conventional 3D ion trap (IT), and (3) quadrupole-linear IT (QqLIT), to determine trace levels of perfluorinated compounds (PFCs) in fish and shellfish were compared. Sample preparation was performed using alkaline extraction and solid-phase-extraction cleanup. This evaluation was focused on both quantitative (sensitivity, precision, and accuracy) and qualitative (identification capabilities) aspects. In the three instruments, the former facet was evaluated using selected reaction monitoring (SRM), which is the standard mode for quantitative LC-MS/MS analysis. Accuracy was similar in the three systems, with recoveries always over 70 %. Precision was better for the QqLIT and QqQ systems (7-15%) than for the IT system (10-17%). The QqLIT (working in SRM mode) and QqQ systems offered a linear dynamic range of at least 3 orders of magnitude, whereas that of the IT system was 2 orders of magnitude. The QqLIT system achieved at least 20-fold higher sensitivity than the QqQ system, and this was at least tenfold higher sensitivity than for the IT system. In the IT system, identification was based on sensitive full mass range acquisition and MS{sup n} fragmentation and in the QqLIT system, it was based on the use of an information-dependent-acquisition scan function, which allows the combination of an SRM or MS full scan acting as the survey scan and an enhanced product ion scan followed by MS{sup 3} as the dependent scan in the same analysis. Three instruments were applied to monitor the content in fish and shellfish (anchovies, swordfish, tuna, mussels, and oysters) obtained from Valencia and Barcelona markets (Spain). The eight target PFCs were detected at mean concentrations in the range from 10 ng kg {sup -1} (perfluoro-7-methyloctanoic acid and perfluoro-1-decanesulfonate) to 4,200 ng kg {sup -1} (perfluoropentanoic acid

  2. Outdoor and indoor benzene evaluation by GC-FID and GC-MS/MS.

    Science.gov (United States)

    Sousa, José A; Domingues, Valentina F; Rosas, Mónica S; Ribeiro, Susana O; Alvim-Ferraz, Conceiçao M; Delerue-Matos, Cristina F

    2011-01-01

    The evaluation of benzene in different environments such as indoor (with and without tobacco smoke), a city area, countryside, gas stations and near exhaust pipes from cars running on different types of fuels was performed. The samples were analyzed using gas chromatography (GC) with flame ionization detection (FID) and tandem mass spectrometric detection (MS/MS) (to confirm the identification of benzene in the air samples). Operating conditions for the GC-MS analysis were optimized as well as the sampling and sample preparation. The results obtained in this work indicate that i) the type of fuel directly influences the benzene concentration in the air. Gasoline with additives provided the highest amount of benzene followed by unleaded gasoline and diesel; ii) the benzene concentration in the gas station was always higher than the advisable limit established by law (5 μg m⁻³) and during the unloading of gasoline the achieved concentration was 8371 μg m⁻³; iii) the data from the countryside (Taliscas) and the urban city (Matosinhos) were below 5 μg m⁻³ except 5 days after a fire on a petroleum refinery plant located near the city; iv) it was proven that in coffee shops where smoking is allowed the benzene concentration is higher (6 μg m⁻³) than in coffee shops where this is forbidden (4 μg m⁻³). This method may also be helpful for environmental analytical chemists who use GC-MS/MS for the confirmation or/and quantification of benzene.

  3. Efficient analysis and extraction of MS/MS result data from Mascot™ result files

    Directory of Open Access Journals (Sweden)

    Sickmann Albert

    2005-12-01

    Full Text Available Abstract Background Mascot™ is a commonly used protein identification program for MS as well as for tandem MS data. When analyzing huge shotgun proteomics datasets with Mascot™'s native tools, limits of computing resources are easily reached. Up to now no application has been available as open source that is capable of converting the full content of Mascot™ result files from the original MIME format into a database-compatible tabular format, allowing direct import into database management systems and efficient handling of huge datasets analyzed by Mascot™. Results A program called mres2x is presented, which reads Mascot™ result files, analyzes them and extracts either selected or all information in order to store it in a single file or multiple files in formats which are easier to handle downstream of Mascot™. It generates different output formats. The output of mres2x in tab format is especially designed for direct high-performance import into relational database management systems using native tools of these systems. Having the data available in database management systems allows complex queries and extensive analysis. In addition, the original peak lists can be extracted in DTA format suitable for protein identification using the Sequest™ program, and the Mascot™ files can be split, preserving the original data format. During conversion, several consistency checks are performed. mres2x is designed to provide high throughput processing combined with the possibility to be driven by other computer programs. The source code including supplement material and precompiled binaries is available via http://www.protein-ms.de and http://sourceforge.net/projects/protms/. Conclusion The database upload allows regrouping of the MS/MS results using a database management system and complex analyzing queries using SQL without the need to run new Mascot™ searches when changing grouping parameters.

  4. Segmental analysis of amphetamines in hair using a sensitive UHPLC-MS/MS method.

    Science.gov (United States)

    Jakobsson, Gerd; Kronstrand, Robert

    2014-06-01

    A sensitive and robust ultra high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method was developed and validated for quantification of amphetamine, methamphetamine, 3,4-methylenedioxyamphetamine and 3,4-methylenedioxy methamphetamine in hair samples. Segmented hair (10 mg) was incubated in 2M sodium hydroxide (80°C, 10 min) before liquid-liquid extraction with isooctane followed by centrifugation and evaporation of the organic phase to dryness. The residue was reconstituted in methanol:formate buffer pH 3 (20:80). The total run time was 4 min and after optimization of UHPLC-MS/MS-parameters validation included selectivity, matrix effects, recovery, process efficiency, calibration model and range, lower limit of quantification, precision and bias. The calibration curve ranged from 0.02 to 12.5 ng/mg, and the recovery was between 62 and 83%. During validation the bias was less than ±7% and the imprecision was less than 5% for all analytes. In routine analysis, fortified control samples demonstrated an imprecision hair demonstrated an imprecision forensic hair samples previously analyzed with an ultra high performance liquid chromatography time of flight mass spectrometry (UHPLC-TOF-MS) screening method. The proposed method was suitable for quantification of these drugs in forensic cases including violent crimes, autopsy cases, drug testing and re-granting of driving licences. This study also demonstrated that if hair samples are divided into several short segments, the time point for intake of a small dose of amphetamine can be estimated, which might be useful when drug facilitated crimes are investigated.

  5. Method-MS, final report 2010

    DEFF Research Database (Denmark)

    Skipperud, Lindis; Popic, Jelena M.; Roos, Per

    (AMS) have shown several advantages compared to traditional methods when measuring long-lived radionuclides. Mass spectrometric methods for determination of very low concentrations of elemental isotopes, and thereby isotopic ratios, have been developed using a variety of ion sources. Although primarily...... applied to the determination of the lighter stable element isotopes and radioactive isotopes in geological studies, the techniques can equally well be applied to the measurement of activity concentrations of long-lived low-level radionuclides in various samples using “isotope dilution” methods...... such as those applied in inductively coupled plasma mass spectrometry (ICP-MS). Due to the low specific activity of long-lived radionuclides, many of these are more conveniently detected using mass spectrometric techniques. Mass spectrometry also enables the individual determination of Pu-239 and Pu-240, which...

  6. HPLC/MS Fingerprint Analysis of Tangshenosides

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    @@Radix codonopsis(党参),which is derived fromCodonopsis pilosula, C.pilosula subsp. Modesta andC. Tangshen(ChP,2000),has been used as a remedy fora decrease of appetite, psychoneurosis, fatigue, dyspepsiaetc.or as a substitute for Panax ginseng in traditionalChinese medicine. Relating to the constituents of theseherbs, triterpenes, phytosterols, furaldehyde, sesquitesand some phenolic glycosides have been reported, butnone of these compounds seems to be responsible for thebiological activities of this drug. As regards the quality evaluation of Radix Codonopsis, a HPLC analysis of atractylenolide Ⅲ has been described, but this sesquiterpene lactone exists in a very low content and is difficultfor conventional analysis. The determination of polysaccharide also met limitation because of its non-specialization. In this paper, we report the HPLC/MS fingerprintsanalysis of phelolic glycosides from Radix Codonopsis including three species.

  7. Semi-automated tandem mass spectrometric (MS/MS) triple quadrupole operating parameter optimization for high-throughput MS/MS detection workflows.

    Science.gov (United States)

    Geddes, Kristin; Adamson, Gary; Dube, Neal; Crathern, Susan; King, Richard C

    2009-05-01

    This paper describes an automated workflow for the determination of selected reaction monitoring (SRM) transitions and optimum mass spectrometric (MS) instrument parameters. The approach uses a Nanomate from Advion Biosciences for automated infusion of small amounts of sample in combination with Automaton optimization software from Sciex. The results are stored in the Analyst software Compound Database for automated acquisition method building. Comparisons are presented between the more traditional optimization methods of manual flow injection optimization, Autotune infusion optimization, Automaton flow injection optimization and the Nanomate-Automaton optimization approach. Data is also presented to show that acquisition methods developed on the Sciex model API3000 instrument can be effectively transferred to the Sceix API4000 and API5000 model instruments. Copyright (c) 2009 John Wiley & Sons, Ltd.

  8. Comparison of GC/time-of-flight MS with GC/quadrupole MS for halocarbon trace gas analysis

    Directory of Open Access Journals (Sweden)

    J. Hoker

    2015-05-01

    Full Text Available We present the application of time-of-flight mass spectrometry (TOF MS for the analysis of halocarbons in the atmosphere after cryogenic sample preconcentration and gas chromatographic separation. For the described field of application, the quadrupole mass spectrometer (QP MS is a state-of-the-art detector. This work aims at comparing two commercially available instruments, a QP MS and a TOF MS, with respect to mass resolution, mass accuracy, stability of the mass axis and instrument sensitivity, detector sensitivity, measurement precision and detector linearity. Both mass spectrometers are operated on the same gas chromatographic system by splitting the column effluent to both detectors. The QP MS had to be operated in optimised single ion monitoring (SIM mode to achieve a sensitivity which could compete with the TOF MS. The TOF MS provided full mass range information in any acquired mass spectrum without losing sensitivity. Whilst the QP MS showed the performance already achieved in earlier tests, the sensitivity of the TOF MS was on average higher than that of the QP MS in the "operational" SIM mode by a factor of up to 3, reaching detection limits of less than 0.2 pg. Measurement precision determined for the whole analytical system was up to 0.2% depending on substance and sampled volume. The TOF MS instrument used for this study displayed significant non-linearities of up to 10% for two-thirds of all analysed substances.

  9. A Screening Method Using LC-MS MS for Illicit Drugs in Postmortem Blood an Application to 62 Postmortem Cases

    Directory of Open Access Journals (Sweden)

    Serap Annette Akgür

    2007-04-01

    Full Text Available Screening of biological specimens in the presence of illicit drugs is of great importance, particularly in criminal cases. The most relevant matrices to be analyzed for this purpose are plasma or blood, due to providing a good correlation between their concentration and pharmacological effects. For majority of laboratories, a common method for screening illicit drugs has been immunoassay methods and Gas Chromatography-coupled with Mass Spectrometry (GC-MS that is widely employed for confirmation purposes. However, the widespread use of liquid chromatography coupled single-stage or tandem mass spectrometry (LC-MS, LC-MS/MS is becoming increasingly significant for both qualitative and quantitative analysis of target analyse which could be polar and thermally labile. This assay method, consisted of morphine, (±-amphetamine, (±-methamphetami-ne, cocaine, benzoylecgonine, cocaethylene and (--ll-nor-9-car-boxy-c9-THC was based on the detection of LC-ESI-MS. In this study, LC-MS/MS method for illicit drugs in postmortem blood was developed. These data provided a documentation to use LC-MS/MS technique without any precipitation for postmortem blood to detect low concentrations of some illicit drugs and applied to 62 postmortem forensic cases. Key words: Illicit drug, screening, LC-MS/MS, postmortem blood

  10. Quantitation of melatonin and n-acetylserotonin in human plasma by nanoflow LC-MS/MS and electrospray LC-MS/MS.

    Science.gov (United States)

    Carter, Melissa D; Calcutt, M Wade; Malow, Beth A; Rose, Kristie L; Hachey, David L

    2012-03-01

    Melatonin (MEL) and its chemical precursor N-acetylserotonin (NAS) are believed to be potential biomarkers for sleep-related disorders. Measurement of these compounds, however, has proven to be difficult due to their low circulating levels, especially that of NAS. Few methods offer the sensitivity, specificity and dynamic range needed to monitor MEL and its precursors and metabolites in small blood samples, such as those obtained from pediatric patients. In support of our ongoing study to determine the safety, tolerability and PK dosing strategies for MEL in treating insomnia in children with autism spectrum disorder, two highly sensitive LC-MS/MS assays were developed for the quantitation of MEL and precursor NAS at pg/mL levels in small volumes of human plasma. A validated electrospray ionization (ESI) method was used to quantitate high levels of MEL in PK studies, and a validated nanospray (nESI) method was developed for quantitation of MEL and NAS at endogenous levels. In both assays, plasma samples were processed by centrifugal membrane dialysis after addition of stable isotopic internal standards, and the components were separated by either conventional LC using a Waters SymmetryShield RP18 column (2.1 × 100  mm, 3.5 µm) or on a polyimide-coated, fused-silica capillary self-packed with 17 cm AquaC18 (3 µm, 125 Å). Quantitation was done using the SRM transitions m/z 233 → 174 and m/z 219 → 160 for MEL and NAS, respectively. The analytical response ratio versus concentration curves were linear for MEL (nanoflow LC: 11.7-1165  pg/mL, LC: 1165-116,500  pg/mL) and for NAS (nanoflow LC: 11.0-1095  pg/mL).

  11. Segmental hair analysis for differentiation of tilidine intake from external contamination using LC-ESI-MS/MS and MALDI-MS/MS imaging.

    Science.gov (United States)

    Poetzsch, Michael; Baumgartner, Markus R; Steuer, Andrea E; Kraemer, Thomas

    2015-02-01

    Segmental hair analysis has been used for monitoring changes of consumption habit of drugs. Contamination from the environment or sweat might cause interpretative problems. For this reason, hair analysis results were compared in hair samples taken 24 h and 30 days after a single tilidine dose. The 24-h hair samples already showed high concentrations of tilidine and nortilidine. Analysis of wash water from sample preparation confirmed external contamination by sweat as reason. The 30-day hair samples were still positive for tilidine in all segments. Negative wash-water analysis proved incorporation from sweat into the hair matrix. Interpretation of a forensic case was requested where two children had been administered tilidine by their nanny and tilidine/nortilidine had been detected in all hair segments, possibly indicating multiple applications. Taking into consideration the results of the present study and of MALDI-MS imaging, a single application as cause for analytical results could no longer be excluded. Interpretation of consumption behaviour of tilidine based on segmental hair analysis has to be done with caution, even after typical wash procedures during sample preparation. External sweat contamination followed by incorporation into the hair matrix can mimic chronic intake. For assessment of external contamination, hair samples should not only be collected several weeks but also one to a few days after intake. MALDI-MS imaging of single hair can be a complementary tool for interpretation. Limitations for interpretation of segmental hair analysis shown here might also be applicable to drugs with comparable physicochemical and pharmacokinetic properties.

  12. Aflatoxins contamination in Pakistani brown rice: a comparison of TLC, HPLC, LC-MS/MS and ELISA techniques.

    Science.gov (United States)

    Iqbal, Javed; Asghar, Muhammad Asif; Ahmed, Aftab; Khan, Mobeen Ahmed; Jamil, Khalid

    2014-12-01

    Advancement in the field of analytical food-chemistry has explored various experimental techniques for aflatoxins (AFs) quantification. The present study was aimed to compare four different techniques; thin-layer chromatography (TLC), high-performance liquid chromatography (HPLC), liquid chromatography-tandem mass spectrometry (LC-MS/MS) and enzyme-linked immunosorbent assay (ELISA) for the analysis of aflatoxin B₁ (AFB₁), B₂ (AFB₂), G₁ (AFG₁) and G₂ (AFG₂) in brown rice (n = 120) being collected from Karachi, Pakistan. All the four assays provide precised, accurate and comparable results. However, some differences were observed. For instance, TLC, HPLC and LC-MS/MS methodologies offered the advantage of the quantification of individual toxins in contrast to ELISA technique. The contamination ranges of AFB₁/AFB₂ as determined by TLC, HPLC and LC-MS/MS were 1.18-9.97/0.59-1.52, 0.16-10.54/0.26-1.35 and 0.11-10.88/0.38-1.48 µg/kg, respectively. However, AFG₁ and AFG₂ were not detected in any tested samples. Furthermore, owing to low-detection limit and sensitivity, HPLC and LC-MS/MS methodologies have identified greater number of contaminated samples in comparison to TLC and ELISA techniques. The overall average results of total AFs as provided by HPLC (3.79 µg/kg) and LC-MS/MS (3.89 µg/kg) were found higher in comparison to TLC (3.68 µg/kg) and ELISA (3.70 µg/kg). On the basis of achieved results, it was concluded that TLC, HPLC, LC-MS/MS and ELISA techniques are valuable tool for the quantification of AFs in cereals and grains. Furthermore, HPLC and LC-MS/MS techniques offer an added advantage for the detection of AFs in diminutive levels.

  13. Title: The validation of Cryogenic Laser Ablation ICP-MS (CLA-ICP-MS) methods by comparison to laser ablation (LA)-ICP-MS and solution based ICP-MS methods, for the analysis of metals in biological tissues

    Science.gov (United States)

    Hannigan, R.; Darrah, T. H.; Horton, M.

    2009-12-01

    ICP-MS and laser ablation ICP-MS (LA-ICP-MS) are well established techniques for the analysis of metals in geological and environmental samples. LA-ICP-MS is commonly used in geological applications to determine the spatial distribution of metal concentrations at small sampling intervals (as low as 10 microns). However, measurement of metals in water-rich, soft biological tissues typically requires samples to be digested into solutions, obfuscating spatial variations in metal concentrations. The cryogenic cell solidifies (by freezing) soft tissue, allowing these tissues to be analyzed by laser ablation for spatial variations in metal concentration. The cell is temperature programmable and capable of maintaining a sample at any temperature between -35C and 25C throughout prolonged analysis. We validate the cryogenic laser ablation ICP-MS (CLA-ICP-MS) method using NIST Glass SRM 612. We also compare metal concentration data analyzed by cryogenic laser ablation ICP-MS (CLA-ICP-MS), LA-ICP-MS, and solution based ICP-MS, for human and rodent brain samples. The cryogenic laser ablation cell will expand analytical capabilities for measuring spatial distribution and concentration of metals incorporated into biological tissues.

  14. Multisteroid LC–MS/MS assay for glucocorticoids and androgens and its application in Addison's disease

    Science.gov (United States)

    Methlie, Paal; Hustad, Steinar; Kellman, Ralf; Almås, Bjørg; Erichsen, Martina M; Husebye, Eystein S; Løvås, Kristian

    2013-01-01

    Objective Liquid chromatography–tandem mass spectrometry (LC–MS/MS) offers superior analytical specificity compared with immunoassays, but it is not available in many regions and hospitals due to expensive instrumentation and tedious sample preparation. Thus, we developed an automated, high-throughput LC–MS/MS assay for simultaneous quantification of ten endogenous and synthetic steroids targeting diseases of the hypothalamic–pituitary–adrenal axis and gonads. Methods Deuterated internal standards were added to 85 μl serum and processed by liquid–liquid extraction. Cortisol, cortisone, prednisolone, prednisone, 11-deoxycortisol, dexamethasone, testosterone, androstenedione and progesterone were resolved by ultra-high-pressure chromatography on a reversed-phase column in 6.1 min and detected by triple-quadrupole mass spectrometry. The method was used to assess steroid profiles in women with Addison's disease (AD, n=156) and blood donors (BDs, n=102). Results Precisions ranged from 4.5 to 10.1% relative standard deviations (RSD), accuracies from 95 to 108% and extraction recoveries from 60 to 84%. The method was practically free of matrix effects and robust to individual differences in serum composition. Most postmenopausal AD women had extremely low androstenedione concentrations, below 0.14 nmol/l, and median testosterone concentrations of 0.15 nmol/l (interquartile range 0.00–0.41), considerably lower than those of postmenopausal BDs (1.28 nmol/l (0.96–1.64) and 0.65 nmol/l (0.56–1.10) respectively). AD women in fertile years had androstenedione concentrations of 1.18 nmol/l (0.71–1.76) and testosterone concentrations of 0.44 nmol/l (0.22–0.63), approximately half of those found in BDs of corresponding age. Conclusion This LC–MS/MS assay provides highly sensitive and specific assessments of glucocorticoids and androgens with low sample volumes and is suitable for endocrine laboratories and research. Its utility has been

  15. Cloud point extraction for analysis of antiretrovirals in human plasma by UFLC-ESI-MS/MS

    Directory of Open Access Journals (Sweden)

    Gabriel A. Hunzicker

    2015-12-01

    Full Text Available An analytical methodology based on cloud point extraction (CPE coupled to Ultra-Fast Liquid Chromatography and electrospray tandem mass spectrometry (UFLC-MS/MS was developed for analysis of Abacavir (ABC, Efavirenz (EFV, Lamivudine (3 TC and Nelfinavir (NFV in human plasma. It is the first time that CPE was used for extraction of antiretrovirals (ARV from plasma. The effects of relevant physic-chemical variables on analytical response of each ARV, including pH, surfactant concentration, equilibration time and temperature, were study and optimized; as well as its coupling to UFLC-ESI-MS/MS. Under optimized conditions, the resulting methodology was as follows: a 500 μL aliquot of human plasma was diluted with 2 mL deionized water in a 10 mL centrifuge tube. A 500 μL aliquot Triton X-114 5% w/v was added and homogenized using a vortex stirrer. The resulting cloudy solution was kept at 65 °C for 20 min for promoting the condensation of surfactant micelles. Then it was centrifuged at 3000 × g for 5 min for separation of the surfactant-rich phase. After discarding the aqueous supernatant, 400 μL ACN were added to the remaining surfactant rich phase and centrifuged in order to precipitate proteins and separate them. A 150 μL aliquot of the supernatant was transferred to 2 mL vial and further diluted with 400 μL deionized water. A 30 μL aliquot of the so-prepared solution was injected and analyzed into the UFLC-MS/MS. The method detection limits for ABC, EFV, 3 TC and NFV under optimized conditions were 31, 77, 57 and 21 ng mL−1, respectively. The RSD% for the studied analytes were <15%, except at the LOQ, which were <19%. Recovery values ranged from 81 to 107%. The proposed methodology was successfully applied for the analysis of ABC, EFV, 3 TC and NFV in human plasma within the concentration range of 43–6816, 125–4992, 81–3248 and 49–7904 ng mL−1, respectively. Under optimized working conditions the proposed

  16. Extraction and analysis of fungal spore biomarkers in atmospheric bioaerosol by HPLC-MS-MS and GC-MS.

    Science.gov (United States)

    Buiarelli, Francesca; Canepari, Silvia; Di Filippo, Patrizia; Perrino, Cinzia; Pomata, Donatella; Riccardi, Carmela; Speziale, Roberto

    2013-02-15

    Airborne microorganisms, as bacteria and fungi, are ubiquitous components of the atmospheric aerosol particles. In this paper, we report a method for the simultaneous extraction, purification, separation, identification and quantification of ergosterol, mannitol and arabitol as biomarkers of fungal spores in bioaerosol particles. After sampling by a low volume sampler, filters were spiked with mannitol-(13)C and dehydrocholesterol as internal standards. Samples were then extracted by accelerated solvent extraction using pure ethanol. The extract was then passed through an amino cartridge and divided in two parts: the apolar fraction, released from the cartridge, was subjected to liquid liquid extraction (by n-hexane), while polar compounds, retained by the cartridge, were eluted by a mixture of methanol-water. The two fractions were joined and analyzed by HPLC equipped with two different columns in series, and coupled to a triple-quadrupole mass spectrometer with Atmospheric Pressure Chemical Ionization source. In addition, the same fractions were analyzed, after derivatization, by GC-MS. The results obtained by the two techniques were finally compared, showing good agreement between them. Last, the contents of the three biomarkers have been estimated in three atmospheric samples collected in a suburban/rural site and, using literature conversion factors, correlated to fungal biomass.

  17. Current advances and strategies towards fully automated sample preparation for regulated LC-MS/MS bioanalysis.

    Science.gov (United States)

    Zheng, Naiyu; Jiang, Hao; Zeng, Jianing

    2014-09-01

    Robotic liquid handlers (RLHs) have been widely used in automated sample preparation for liquid chromatography-tandem mass spectrometry (LC-MS/MS) bioanalysis. Automated sample preparation for regulated bioanalysis offers significantly higher assay efficiency, better data quality and potential bioanalytical cost-savings. For RLHs that are used for regulated bioanalysis, there are additional requirements, including 21 CFR Part 11 compliance, software validation, system qualification, calibration verification and proper maintenance. This article reviews recent advances in automated sample preparation for regulated bioanalysis in the last 5 years. Specifically, it covers the following aspects: regulated bioanalysis requirements, recent advances in automation hardware and software development, sample extraction workflow simplification, strategies towards fully automated sample extraction, and best practices in automated sample preparation for regulated bioanalysis.

  18. Simultaneous quantitative analysis of salivary cortisol and cortisone in Korean adults using LC-MS/MS.

    Science.gov (United States)

    Lee, Sanghoo; Kwon, Soonho; Shin, Hye-Jin; Lim, Hwan-Sub; Singh, Ravinder J; Lee, Kyoung-Ryul; Kim, Young-Jin

    2010-07-01

    The levels of salivary cortisol and cortisone in Korean adults were measured for the first time using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The salivary cortisol and cortisone were separated within 10 min. The regression coefficients (r) of the calibration curves were greater than 0.999 for the two steroids. The limits of quantitation (LOQ) were 0.2 ng/ml for cortisol and 1 ng/ml for cortisone. The intra-day precisions of the assay were cortisone respectively, and the inter-day precisions were cortisone, respectively. The salivary cortisone concentrations were approximately 4-9 times higher than those of salivary cortisol during the daytime. Diurnal rhythms, during which the cortisol and cortisone concentrations were higher in the morning than in the afternoon, were also observed. The present assay may be useful for the diagnosis of several adrenal dysfunctions in clinical biochemistry.

  19. HPLC-DAD-ESI-MS/MS screening of bioactive components from Rhus coriaria L. (Sumac) fruits.

    Science.gov (United States)

    Abu-Reidah, Ibrahim M; Ali-Shtayeh, Mohammed S; Jamous, Rana M; Arráez-Román, David; Segura-Carretero, Antonio

    2015-01-01

    Rhus coriaria L. (sumac) is an important crop widely used in the Mediterranean basin as a food spice, and also in folk medicine, due to its health-promoting properties. Phytochemicals present in plant foods are in part responsible for these consequent health benefits. Nevertheless, detailed information on these bioactive compounds is still scarce. Therefore, the present work was aimed at investigating the phytochemical components of sumac fruit epicarp using HPLC-DAD-ESI-MS/MS in two different ionisation modes. The proposed method provided tentative identification of 211 phenolic and other phyto-constituents, most of which have not been described so far in R. coriaria fruits. More than 180 phytochemicals (tannins, (iso)flavonoids, terpenoids, etc.) are reported herein in sumac fruits for the first time. The obtained results highlight the importance of R. coriaria as a promising source of functional ingredients, and boost its potential use in the food and nutraceutical industries.

  20. Quantitation of sweet steviol glycosides by means of a HILIC-MS/MS-SIDA approach.

    Science.gov (United States)

    Well, Caroline; Frank, Oliver; Hofmann, Thomas

    2013-11-27

    Meeting the rising consumer demand for natural food ingredients, steviol glycosides, the sweet principle of Stevia rebaudiana Bertoni (Bertoni), have recently been approved as food additives in the European Union. As regulatory constraints require sensitive methods to analyze the sweet-tasting steviol glycosides in foods and beverages, a HILIC-MS/MS method was developed enabling the accurate and reliable quantitation of the major steviol glycosides stevioside, rebaudiosides A-F, steviolbioside, rubusoside, and dulcoside A by using the corresponding deuterated 16,17-dihydrosteviol glycosides as suitable internal standards. This quantitation not only enables the analysis of the individual steviol glycosides in foods and beverages but also can support the optimization of breeding and postharvest downstream processing of Stevia plants to produce preferentially sweet and least bitter tasting Stevia extracts.

  1. Evaluation of Acrylamide in Food from China by a LC/MS/MS Method

    Science.gov (United States)

    Chen, Yong-Hong; Xia, En-Qin; Xu, Xiang-Rong; Ling, Wen-Hua; Li, Sha; Wu, Shan; Deng, Gui-Fang; Zou, Zhi-Fei; Zhou, Jing; Li, Hua-Bin

    2012-01-01

    Acrylamide is potential carcinogenic compound that possesses neurotoxicity activity. In this study, the levels of acrylamide in 123 selected food samples from China was evaluated using a LC/MS/MS method. One hundred and fifteen (115) out of 123 samples showed positive levels of acrylamide in the range of 0.41 to 4,126.26 µg/kg. Generally, the highest acrylamide levels were found in fried products, such as potato, prawn strips and rice crust, with average values of 604.27, 341.40, and 201.51 µg/kg, respectively. Heated protein-rich food also showed some acrylamide content (ranging from 2.31 to 78.57 µg/kg). The results revealed that a potential acrylamide public health risk occurred in processed snacks, as well as the food consumed daily. This study supplied new information on acrylamide content of a variety of heat-treated foods from China. PMID:23202837

  2. Rapid and reproducible determination of active gibberellins in citrus tissues by UPLC/ESI-MS/MS.

    Science.gov (United States)

    Manzi, Matías; Gómez-Cadenas, Aurelio; Arbona, Vicent

    2015-09-01

    Phytohormone determination is crucial to explain the physiological mechanisms during growth and development. Therefore, rapid and precise methods are needed to achieve reproducible determination of phytohormones. Among many others, gibberellins (GAs) constitute a family of complex analytes as most of them share similar structure and chemical properties although only a few hold biological activity (namely GA1; GA3; GA4 and GA7). A method has been developed to extract GAs from plant tissues by mechanical disruption using ultrapure water as solvent and, in this way, ion suppression was reduced whereas sensitivity increased. Using this methodology, the four active GAs were separated and quantified by UPLC coupled to MS/MS using the isotope-labeled internal standards [(2)H2]-GA1 and [(2)H2]-GA4. To sum up, the new method provides a fast and reproducible protocol to determine bioactive GAs at low concentrations, using minimal amounts of sample and reducing the use of organic solvents.

  3. Streamlining the analytical workflow for multiplex MS/MS allergen detection in processed foods.

    Science.gov (United States)

    Pilolli, Rosa; De Angelis, Elisabetta; Monaci, Linda

    2017-04-15

    Allergenic ingredients in pre-packaged foods are regulated by EU legislation mandating their inclusion on labels. In order to protect allergic consumers, sensitive analytical methods are required for detect allergen traces in different food products. As a follow-up to our previous investigations, an optimized, sensitive, label-free LC-MS/MS method for multiplex detection of five allergenic ingredients in a processed food matrix is proposed. A cookie base was chosen as a complex food matrix and home-made cookies incurred with whole egg, skimmed milk, soy flour, ground hazelnut and ground peanut were prepared at laboratory scale. In order to improve the analytical workflow both protein extraction and purification protocols were optimized and finally a sensitive streamlined SRM based analytical method for allergens detection in incurred cookies was devised. The effect of baking on the detection of selected markers was also investigated. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Phytochemical analysis of Pfaffia glomerata inflorescences by LC-ESI-MS/MS.

    Science.gov (United States)

    Felipe, Daniele F; Brambilla, Lara Z S; Porto, Carla; Pilau, Eduardo J; Cortez, Diógenes A G

    2014-09-29

    Pfaffia glomerata contains high levels of β-ecdysone, which has shown a range of beneficial pharmacological effects. The present study demonstrated that inflorescences of P. glomerata contain other important bioactive compounds in addition to β-ecdysone. The identification of compounds from inflorescences using liquid chromatography coupled with electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) was performed for the first time. The eight compounds identified were β-ecdysone, flavonoid glycosides such as quercetin-3-O-glucoside, kaempferol-3-O-glucoside and kaempferol-3-O-(6-p-coumaroyl)-glucoside, oleanane-type triterpenoid saponins such as ginsenoside Ro and chikusetsusaponin IV, in addition to oleanonic acid and gluconic acid. This study provided information on the phytochemicals contained in P. glomerata inflorescences revealing the potential application of this plant part as raw material for the phytotherapeutic and cosmetic industries.

  5. Phytochemical Analysis of Pfaffia glomerata Inflorescences by LC-ESI-MS/MS

    Directory of Open Access Journals (Sweden)

    Daniele F. Felipe

    2014-09-01

    Full Text Available Pfaffia glomerata contains high levels of β-ecdysone, which has shown a range of beneficial pharmacological effects. The present study demonstrated that inflorescences of P. glomerata contain other important bioactive compounds in addition to β-ecdysone. The identification of compounds from inflorescences using liquid chromatography coupled with electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS was performed for the first time. The eight compounds identified were β-ecdysone, flavonoid glycosides such as quercetin-3-O-glucoside, kaempferol-3-O-glucoside and kaempferol-3-O-(6-p-coumaroyl-glucoside, oleanane-type triterpenoid saponins such as ginsenoside Ro and chikusetsusaponin IV, in addition to oleanonic acid and gluconic acid. This study provided information on the phytochemicals contained in P. glomerata inflorescences revealing the potential application of this plant part as raw material for the phytotherapeutic and cosmetic industries.

  6. Multiplexed LC-MS/MS analysis of horse plasma proteins to study doping in sport.

    Science.gov (United States)

    Barton, Chris; Beck, Paul; Kay, Richard; Teale, Phil; Roberts, Jane

    2009-06-01

    The development of protein biomarkers for the indirect detection of doping in horse is a potential solution to doping threats such as gene and protein doping. A method for biomarker candidate discovery in horse plasma is presented using targeted analysis of proteotypic peptides from horse proteins. These peptides were first identified in a novel list of the abundant proteins in horse plasma. To monitor these peptides, an LC-MS/MS method using multiple reaction monitoring was developed to study the quantity of 49 proteins in horse plasma in a single run. The method was optimised and validated, and then applied to a population of race-horses to study protein variance within a population. The method was finally applied to longitudinal time courses of horse plasma collected after administration of an anabolic steroid to demonstrate utility for hypothesis-driven discovery of doping biomarker candidates.

  7. Contribution to the characterization of Opuntia spp. juices by LC-DAD-ESI-MS/MS.

    Science.gov (United States)

    Mata, A; Ferreira, J P; Semedo, C; Serra, T; Duarte, C M M; Bronze, M R

    2016-11-01

    Opuntia spp. fruits are considered as health promoting foods due to the diversity of bioactive molecules found in these fruits. The composition in organic acids, flavonols and betalains in the Opuntia ficus-indica juice from a region of Portugal was accomplished for the first time by liquid chromatography and tandem mass spectrometry using an electrospray ionization source operating in negative and positive mode. The methodology used allowed the detection of 44 compounds, from which 32 were identified. Isorhamnetin derivatives were the dominant flavonol glycosides. A total of 9 betalains including 6 betaxanthins and 3 betacyanin were also detected in the fruit juice samples and indicaxanthin, betanin and isobetanin were the major pigments. Phenolic acid and phenylpyruvic acid derivatives were also identified. To our knowledge, it is the first time derivative compounds from piscidic acid, phenolic compounds and betalains are characterized in cactus pear juice using a single LC-DAD-ESI-MS/MS method.

  8. The detection of sedatives in hair and nail samples using tandem LC-MS-MS.

    Science.gov (United States)

    Irving, Rachel C; Dickson, Stuart J

    2007-02-14

    Drug screening methods were developed to detect alprazolam, clobazam, clonazepam, diazepam, midazolam, oxazepam, temazepam, triazolam, zopiclone, and selected metabolites in human hair and nail samples employing liquid-liquid extraction and tandem liquid chromatography-mass spectrometry (LC-MS-MS). Hair and nail samples were obtained from patients who had recently discontinued or were currently prescribed one or more of the targeted drugs. Prazepam was used as the internal standard for all compounds. Some components in the hair matrix gave the same transitions as some of the analytes but did not compromise the analyses because their retention times differed from those for the target compounds. The analytical run time was 8-10min. Results of the hair analysis of a DFSA victim are also presented.

  9. Pyrolysis Process in Aramid Fibers Investigated by Py-GC/MS & TGA-DTA/MS

    Institute of Scientific and Technical Information of China (English)

    WANG Xin-wei; HU Zu-ming; LIU Zhao-feng

    2007-01-01

    Poly(m-phenylene isophthalamine) (PMIA) and Poly( p-phenylene terphthalamine) (PPTA) are among the most important high-temperature resistant aramid fibers. The pyrolysis behaviors of these two fibers under inert gases were studied using pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) and thermogravimetric analysis coupled with mass spectrometry ( TGA-DTA/MS ). The pyrolysis processes of PMIA and PPTA are distinguishing, and the stepwise pyrolysates reflect these differences. A mechanism system of pyrolysis is suggested, which involving hydrolysis and homolysis. At low pyrolysis temperatures, hydrolysis is a primary reaction, and it is very noticeable in the first-step pyrolysis region of PMIA. Elevating pyrolysis temperature, homolysis is enhanced and keep a large advantage in the high temperature range. On the other hand, at higher temperatures, carbonization appens and the homolysis and carbonization of PPTA are emphasized more than of PMIA.

  10. Determination of phenolic compounds in Yucca gloriosa bark and root by LC-MS/MS.

    Science.gov (United States)

    Montoro, Paola; Skhirtladze, Alexandre; Bassarello, Carla; Perrone, Angela; Kemertelidze, Ether; Pizza, Cosimo; Piacente, Sonia

    2008-08-05

    On the basis of the biological activities shown by yuccaols and gloriosaols from Yucca schidigera and Yucca gloriosa, the content of yuccaols and gloriosaols in two different parts of Y. gloriosa (roots and bark), was determined for each single compound, and compared with phenolic determination in Y. schidigera bark, concluding that Y. gloriosa bark and roots are rich sources of phenolic derivatives structurally related to resveratrol. LC/ESIMS (liquid chromatography coupled to electrospray mass spectrometry) qualitative and an LC/ESIMS/MS (liquid chromatography coupled to tandem electrospray mass spectrometry) quantitative studies of the phenolic fraction of Y. gloriosa were performed. LC/ESIMS/MS multiple reaction monitoring (MRM) method previously described for yuccaols in Y. schidigera was applied and optimised for separation and determination of gloriosaols and yuccaols in Y. gloriosa. Due to the sensitivity and the repeatability of the assay, we suggest this method as suitable for industrial quality control of raw materials and final products.

  11. Identification of Penicillin G Metabolites under Various Environmental Conditions Using UHPLC-MS/MS.

    Science.gov (United States)

    Aldeek, Fadi; Canzani, Daniele; Standland, Matthew; Crosswhite, Mark R; Hammack, Walter; Gerard, Ghislain; Cook, Jo-Marie

    2016-08-10

    In this work, we investigate the stability of penicillin G in various conditions including acidic, alkaline, natural acidic matrices and after treatment of citrus trees that are infected with citrus greening disease. The identification, confirmation, and quantitation of penicillin G and its various metabolites were evaluated using two UHPLC-MS/MS systems with variable capabilities (i.e., Thermo Q Exactive Orbitrap and Sciex 6500 QTrap). Our data show that under acidic and alkaline conditions, penicillin G at 100 ng/mL degrades quickly, with a determined half-life time of approximately 2 h. Penillic acid, penicilloic acid, and penilloic acid are found to be the most abundant metabolites of penicillin G. These major metabolites, along with isopenillic acid, are found when penicillin G is used for treatment of citrus greening infected trees. The findings of this study will provide insight regarding penicillin G residues in agricultural and biological applications.

  12. Quantitative determination of amisulpride in rat plasma by HPLC-MS/MS.

    Science.gov (United States)

    Noh, Keumhan; Jang, Yoo-Jeong; Kwon, Kwang-il; Kim, Eunyoung; Jeong, Tae Cheon; Yun, Hwi-yeol; Kang, Wonku

    2015-01-01

    Amisulpride, a selective antagonist of D2 and D3 dopamine receptors, is used as an antipsychotic drug. In this study, we reported a sensitive LC-MS/MS method for determining amisulpride concentrations in rat plasma, and a preclinical pharmacokinetic study in the rat. After a simple protein precipitation with acetonitrile containing methaqualone as an internal standard, the analytes were separated on a reversed-phase column with a mobile phase of 0.2 % aqueous formic acid and acetonitrile (3:7, v/v). The accuracy and precision of the assay were in accordance with FDA guidance for the validation of bioanalytical methods. This analytical method was used successfully to characterize the time course of the plasma concentration of amisulpride following oral administration of a single 10 mg/kg dose in rats.

  13. Novel liquid chromatography tandem mass spectrometry (LC-MS/MS) methods for measuring steroids.

    Science.gov (United States)

    Keevil, Brian G

    2013-10-01

    Liquid chromatography tandem mass spectrometry (LC-MS/MS) is increasingly becoming the method of choice for steroid hormone measurements due to small sample volumes, fast analysis times and improved specificity compared to immunoassays. Achievement of demanding analytical targets for steroid analysis is now becoming possible because of improvements in sample preparation technology, liquid chromatography column technology and mass spectrometer design. The most popular sample treatment strategies comprise protein precipitation (PP), solid-phase extraction (SLE) and liquid-liquid extraction (LLE). Modern liquid chromatography columns can ensure the adequate separation of isobaric compounds e.g. 21 Deoxycortisol, 11 Deoxycortisol and Corticosterone. The most appropriate method may be chosen to improve assay sensitivity by reducing matrix effects (LLE, SPE) or simplicity and speed (PP). Specific examples of some clinically important steroids including oestradiol, aldosterone, renin, serum cortisol, salivary cortisol and salivary testosterone will be described.

  14. LC-MS/MS Peptide Mapping with Automated Data Processing for Routine Profiling of N-Glycans in Immunoglobulins

    Science.gov (United States)

    Shah, Bhavana; Jiang, Xinzhao Grace; Chen, Louise; Zhang, Zhongqi

    2014-06-01

    Protein N-Glycan analysis is traditionally performed by high pH anion exchange chromatography (HPAEC), reversed phase liquid chromatography (RPLC), or hydrophilic interaction liquid chromatography (HILIC) on fluorescence-labeled glycans enzymatically released from the glycoprotein. These methods require time-consuming sample preparations and do not provide site-specific glycosylation information. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) peptide mapping is frequently used for protein structural characterization and, as a bonus, can potentially provide glycan profile on each individual glycosylation site. In this work, a recently developed glycopeptide fragmentation model was used for automated identification, based on their MS/MS, of N-glycopeptides from proteolytic digestion of monoclonal antibodies (mAbs). Experimental conditions were optimized to achieve accurate profiling of glycoforms. Glycan profiles obtained from LC-MS/MS peptide mapping were compared with those obtained from HPAEC, RPLC, and HILIC analyses of released glycans for several mAb molecules. Accuracy, reproducibility, and linearity of the LC-MS/MS peptide mapping method for glycan profiling were evaluated. The LC-MS/MS peptide mapping method with fully automated data analysis requires less sample preparation, provides site-specific information, and may serve as an alternative method for routine profiling of N-glycans on immunoglobulins as well as other glycoproteins with simple N-glycans.

  15. Identification and Quantification of Loline-Type Alkaloids in Endophyte-Infected Grasses by LC-MS/MS.

    Science.gov (United States)

    Adhikari, Khem B; Boelt, Birte; Fomsgaard, Inge S

    2016-08-10

    Lolines, fungal metabolites of the grass-endophyte association, were identified and quantified using newly developed LC-MS/MS methods in endophyte-infected grasses belonging to the Lolium and Festuca genera after extraction with three different solvents using two extraction methods. The shaking extraction method with isopropanol/water was superior to the other methods due to its high sensitivity, high accuracy (recovery within or close to the range of 80-120%), and high precision (coefficient of variation of <10%). Seven loline alkaloids were identified and quantified using our newly established LC-MS/MS methods, and N-formylloline was the most abundant (5 mg/g dry matter), followed by N-acetylloline. These LC-MS/MS methods used the shortest sample handling time and the fewest sample preparation steps and proved to be good alternatives to existing GC and GC-MS analytical methods without compromising analytical efficiency. In conclusion, we developed for the first time a highly sensitive quantitative LC-MS/MS analytical method for the accurate and reproducible quantification and a LightSight-assisted LC-QTRAP/MS qualitative method for the tentative identification of loline-type alkaloids in endophyte-infected grasses.

  16. Development and validation of an LC-MS/MS sulfonylurea assay for hypoglycemia cases in the emergency department.

    Science.gov (United States)

    Yang, He S; Wu, Alan H B; Johnson-Davis, Kamisha L; Lynch, Kara L

    2016-02-15

    Sulfonylureas are antidiabetic agents widely prescribed for the treatment of type-II diabetes. Detection of the presence of sulfonylureas in cases of unexplained hypoglycemia rules out other underlying pathophysiological conditions. The goal of this study was to develop and validate a qualitative liquid chromatography tandem mass spectrometry (LC-MS/MS) assay for the rapid identification of sulfonylureas in serum. An LC-MS/MS assay was developed using an Agilent HPLC with an AB Sciex 3200 LC-MS/MS operating in ESI positive mode. Linearity, LOD, precision, matrix effect, recovery, carry-over and stability of the final method were evaluated for method validation. Concordance with another clinically validated LC-MS/MS method was evaluated using remnant samples from patients prescribed a sulfonylurea. The assay performed well with all validation data meeting pre-determined criteria. The method comparison study showed a correlation coefficient of 0.99 for glipizide, the most common sulfonylurea, despite both methods being validated as qualitative methods. To date the validated assay has been utilized in 19 cases of unexplained hypoglycemia presenting to the emergency department, in which 5 were sulfonylurea positive. We have developed a rapid and sensitive LC-MS/MS sulfonylurea assay, and utilized this assay to assist in the differential diagnosis of unexplained hypoglycemia. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. Analysis of biofluids by paper spray MS: advances and challenges.

    Science.gov (United States)

    Manicke, Nicholas E; Bills, Brandon J; Zhang, Chengsen

    2016-03-01

    Paper spray MS is part of a cohort of ambient ionization or direct analysis methods that seek to analyze complex samples without prior sample preparation. Extraction and electrospray ionization occur directly from the paper substrate upon which a dried matrix spot is stored. Paper spray MS is capable of detecting drugs directly from dried blood, plasma and urine spots at the low ng/ml to pg/ml levels without sample preparation. No front end separation is performed, so MS/MS or high-resolution MS is required. Here, we discuss paper spray methodology, give a comprehensive literature review of the use of paper spray MS for bioanalysis, discuss technological advancements and variations on this technique and discuss some of its limitations.

  18. LC-MS/MS Analysis Unravels Deep Oxidation of Manganese Superoxide Dismutase in Kidney Cancer

    Directory of Open Access Journals (Sweden)

    Zuohui Zhao

    2017-02-01

    Full Text Available Manganese superoxide dismutase (MNSOD is one of the major scavengers of reactive oxygen species (ROS in mitochondria with pivotal regulatory role in ischemic disorders, inflammation and cancer. Here we report oxidative modification of MNSOD in human renal cell carcinoma (RCC by the shotgun method using data-dependent liquid chromatography tandem mass spectrometry (LC-MS/MS. While 5816 and 5571 proteins were identified in cancer and adjacent tissues, respectively, 208 proteins were found to be up- or down-regulated (p < 0.05. Ontological category, interaction network and Western blotting suggested a close correlation between RCC-mediated proteins and oxidoreductases such as MNSOD. Markedly, oxidative modifications of MNSOD were identified at histidine (H54 and H55, tyrosine (Y58, tryptophan (W147, W149, W205 and W210 and asparagine (N206 and N209 residues additional to methionine. These oxidative insults were located at three hotspots near the hydrophobic pocket of the manganese binding site, of which the oxidation of Y58, W147 and W149 was up-regulated around three folds and the oxidation of H54 and H55 was detected in the cancer tissues only (p < 0.05. When normalized to MNSOD expression levels, relative MNSOD enzymatic activity was decreased in cancer tissues, suggesting impairment of MNSOD enzymatic activity in kidney cancer due to modifications. Thus, LC-MS/MS analysis revealed multiple oxidative modifications of MNSOD at different amino acid residues that might mediate the regulation of the superoxide radicals, mitochondrial ROS scavenging and MNSOD activity in kidney cancer.

  19. LC-MS/MS screening method for designer amphetamines, tryptamines, and piperazines in serum.

    Science.gov (United States)

    Wohlfarth, Ariane; Weinmann, Wolfgang; Dresen, Sebastian

    2010-04-01

    Since the late 1990s and early 2000s, derivatives of well-known designer drugs as well as new psychoactive compounds have been sold on the illicit drug market and have led to intoxications and fatalities. The LC-MS/MS screening method presented covers 31 new designer drugs as well as cathinone, methcathinone, phencyclidine, and ketamine which were included to complete the screening spectrum. All but the last two are modified molecular structures of amphetamine, tryptamine, or piperazine. Among the amphetamine derivatives are cathinone, methcathinone, 3,4-DMA, 2,5-DMA, DOB, DOET, DOM, ethylamphetamine, MDDMA, 4-MTA, PMA, PMMA, 3,4,5-TMA, TMA-6 and members of the 2C group: 2C-B, 2C-D, 2C-H, 2C-I, 2C-P, 2C-T-2, 2C-T-4, and 2C-T-7. AMT, DPT, DiPT, MiPT, DMT, and 5MeO-DMT are contained in the tryptamine group, BZP, MDBP, TFMPP, mCPP, and MeOPP in the piperazine group. Using an Applied Biosystems LC-MS/MS API 365 TurboIonSpray it is possible to identify all 35 substances. After addition of internal standards and mixed-mode solid-phase extraction the analytes are separated using a Synergi Polar RP column and gradient elution with 1 mM ammonium formate and methanol/0.1% formic acid as mobile phases A and B. Data acquisition is performed in MRM mode with positive electro spray ionization. The assay is selective for all tested substances. Limits of detection were determined by analyzing S/N-ratios and are between 1.0 and 5.0 ng/mL. Matrix effects lie between 65% and 118%, extraction efficiencies range from 72% to 90%.

  20. LC-MS/MS based proteomic analysis and functional inference of hypothetical proteins in Desulfovibrio vulgaris.

    Science.gov (United States)

    Zhang, Weiwen; Culley, David E; Gritsenko, Marina A; Moore, Ronald J; Nie, Lei; Scholten, Johannes C M; Petritis, Konstantinos; Strittmatter, Eric F; Camp, David G; Smith, Richard D; Brockman, Fred J

    2006-11-03

    High efficiency capillary liquid chromatography-tandem mass spectrometry (LC-MS/MS) was used to examine the proteins extracted from Desulfovibrio vulgaris cells across six treatment conditions. While our previous study provided a proteomic overview of the cellular metabolism based on proteins with known functions [W. Zhang, M.A. Gritsenko, R.J. Moore, D.E. Culley, L. Nie, K. Petritis, E.F. Strittmatter, D.G. Camp II, R.D. Smith, F.J. Brockman, A proteomic view of the metabolism in Desulfovibrio vulgaris determined by liquid chromatography coupled with tandem mass spectrometry, Proteomics 6 (2006) 4286-4299], this study describes the global detection and functional inference for hypothetical D. vulgaris proteins. Using criteria that a given peptide of a protein is identified from at least two out of three independent LC-MS/MS measurements and that for any protein at least two different peptides are identified among the three measurements, 129 open reading frames (ORFs) originally annotated as hypothetical proteins were found to encode expressed proteins. Functional inference for the conserved hypothetical proteins was performed by a combination of several non-homology based methods: genomic context analysis, phylogenomic profiling, and analysis of a combination of experimental information, including peptide detection in cells grown under specific culture conditions and cellular location of the proteins. Using this approach we were able to assign possible functions to 20 conserved hypothetical proteins. This study demonstrated that a combination of proteomics and bioinformatics methodologies can provide verification of the expression of hypothetical proteins and improve genome annotation.

  1. LC-MS/MS detection of unaltered glucuronoconjugated metabolites of metandienone.

    Science.gov (United States)

    Esquivel, Argitxu; Pozo, Oscar J; Garrostas, Lorena; Balcells, Georgina; Gómez, Cristina; Kotronoulas, Aristotelis; Joglar, Jesús; Ventura, Rosa

    2016-05-30

    The aim of this study was to evaluate the direct detection of glucuronoconjugated metabolites of metandienone (MTD) and their detection times. Metabolites resistant to enzymatic hydrolysis were also evaluated. Based on the common mass spectrometric behaviour of steroid glucuronides, three liquid chromatography-tandem mass spectrometry (LC-MS/MS) strategies were applied for the detection of unpredicted and predicted metabolites: precursor ion scan (PI), neutral loss scan (NL), and theoretical selected reaction monitoring (SRM) methods. Samples from four excretion studies of MTD were analyzed for both the detection of metabolites and the establishment of their detection times. Using PI and NL methods, seven metabolites were observed in post-administration samples. SRM methods allowed for the detection of 13 glucuronide metabolites. The detection times, measured by analysis with an SRM method, were between 1 and 22 days. The metabolite detected for the longest time was 18-nor-17β-hydroxymethyl-17α-methyl-5β-androsta-1,4,13-triene-3-one-17-glucuronide. One metabolite was resistant to hydrolysis with β-glucuronidase; however it was only detected in urine up to four days after administration. The three glucuronide metabolites with the highest retrospectivity were identified by chemical synthesis or mass spectrometric data, and although they were previously reported, this is the first time that analytical data of the intact phase II metabolites are presented for some of them. The LC-MS/MS strategies applied have demonstrated to be useful for detecting glucuronoconjugated metabolites of MTD, including glucuronides resistant to enzymatic hydrolysis which cannot be detected by conventional approaches. Copyright © 2016 John Wiley & Sons, Ltd.

  2. Methylmalonic acid quantification in low serum volumes by UPLC-MS/MS.

    Science.gov (United States)

    Pedersen, Theresa L; Keyes, William R; Shahab-Ferdows, Setareh; Allen, Lindsay H; Newman, John W

    2011-06-01

    Methylmalonic acid (MMA) is a metabolic intermediate transformed to succinic acid (SA) by a vitamin B(12)-dependent catalytic step, and is broadly used as a clinical biomarker of functional vitamin B12 status. However, reported methods use between 100 and 1000 μL of serum or plasma making them sub-optimal for sample-limited studies, including those with neonates and infants. LC-MS/MS based protocols to measure MMA as n-butyl esters in the presence of tri-deuterated MMA (MMA-d(3)) were modified for use with 25 μL of human serum by scaling down sample processing volumes and analysis by UPLC-MS/MS. Plasma-based calibration solutions were found to be unnecessary, and chromatographic resolution and peak shape of SA and MMA was optimized in cyclohexyl-urido-3-dodecanoic acid (CUDA) was included as internal standard allowing direct assessment of MMA recovery. Sample concentrations in the low normal range produced a signal:noise of >100:1. MMA intra- and inter-assay variability was under 10%. MMA-d(3) surrogate recovery averaged 93±14%. MMA stability exceeded three years in frozen samples and was unaffected by up to five freeze/thaw cycles. In conclusion, we report that methylmalonic acid can be measured with 25 μL of serum using water based standards. The assay signal:noise per concentration indicates that the method could perform as implemented with as little as 5 μL of serum. The reported method is applicable for studies of functional B12 status in sample limited experiments including investigations of nutritional status in neonates and in studies where low normal MMA levels are expected.

  3. Application of UPLC-MS/MS Method for Analyzing B-vitamins in Human Milk

    Institute of Scientific and Technical Information of China (English)

    REN Xiang Nan; YIN Shi An; YANG Zhen Yu; YANG Xiao Guang; SHAO Bing; REN Yi Ping; ZHANG Jing

    2015-01-01

    Objective To determine ten B-vitamins in human milk by ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). Methods The pretreated human milk samples were adequately separated and quantified within 11 min by UPLC-MS/MS with an Acquity UPLC HSS T3 column (2.1×100 mm, 1.8 µm). The mobile phase was a gradient of 2.5 mmol/L ammonium formate aqueous solution and acetonitrile at a flow rate of 0.35 mL/min. Stable isotope internal standards were used in the analysis, to correct for the method variability, including matrix and ionization effects. The homogenized human milk samples were deproteinzed using methanol, unknown contaminants were extracted with diethyl ether and hydrophobic phase was discarded. The analytes were monitored via ESI+ionization and detected in multiple reaction monitoring (MRM) with three acquisition functions. Results Calibration curves ranged from 0.5-160 ng/mL (thiamin, riboflavin, biotin, nicotinic acid, pyridoxine, pyridoxamine, pyridoxal), and 2.5-800 ng/mL (pantothenic acid, FAD and nicotinamide) (R2=0.990-0.999). The relative recovery ranged from 80.1% to 120.2%; accuracy was determined to be 98.3% to 108.0%. Intra-day and inter-day variation were 3.4%-19.9% and 5.9%-18.1%, respectively. The limit of quantification (LOQ) for all vitamins was between 0.25 and 3 µg/L. Conclusion This method was successfully applied for simultaneous analysis of ten B-vitamins in human milk.

  4. Therapeutic monitoring of amphotericin B in Saudi ICU patients using UPLC MS/MS assay.

    Science.gov (United States)

    Al-Quadeib, Bushra T; Radwan, Mahasen A; Siller, Lidija; Mutch, Elaine; Horrocks, Ben; Wright, Matthew; Alshaer, Abdulaziz

    2014-12-01

    Amphotericin B (AmB) is the first-line agent for the treatment of life-threatening invasive fungal infections. The aim of this study was to monitor AmB in critically ill Saudi patients in ICU after i.v. administration of 0.68 ± 0.1 mg/kg/day Fungizone®. A selective, sensitive and precise UPLC MS/MS method was developed to measure AmB concentrations in these patients. Seven ICU patients with creatinine clearance (ClCr) >40 mL/min were included. AmB levels were analyzed using a Waters Aquity UPLC MS/MS system, a BEH Shield RP18 column and detection via electrospray ionization source with positive ionization mode. The precision and accuracy of the developed UPLC method in the concentration range of 200-4000 ng/mL show no significant difference among inter- and-intra-day analysis (p > 0.05). Linearity was observed over the investigated range with correlation coefficient, r > 0.995 (n = 6/day). The pharmacokinetics of AmB in these patients, at steady state, showed a high terminal half-life of 124.6 ± 73.4 h, with a highest concentration of 513.9 ± 281.1 ng/mL, a lowest concentration 316.4 ± 129.0 ng/mL and a mean clearance 91.1 ± 39.2 mL/h/kg. The pharmacokinetics of AmB in critically ill Saudi patients in ICU was studied using a fully validated assay. A weak correlation (r = -0.22) of AmB Cl with ClCr was obtained, which suggests the need for further investigation in a larger population.

  5. Robust HPLC-MS/MS method for levofloxacin and ciprofloxacin determination in human prostate tissue.

    Science.gov (United States)

    Szerkus, O; Jacyna, J; Gibas, A; Sieczkowski, M; Siluk, D; Matuszewski, M; Kaliszan, R; Markuszewski, M J

    2017-01-05

    Fluoroquinolones are the drugs of choice in the prevention of bacterial infections after transrectal ultrasound guided prostate biopsy. In order to improve assessment of antibacterial efficacy in the target tissue a simple, selective, rapid and robust HPLC-ESI-MS/MS method for the determination of levofloxacin and ciprofloxacin concentrations in human prostate bioptates was developed and validated. Preparation procedure for prostate samples (10mg) was carried out using homogenization and filtration steps. Analyses were performed within 3.5min using RP C18 column in the isocratic elution mode with mobile phase composed of a mixture of 0.1% formic acid aqueous solution and 0.1% formic acid methanol solution (v/v; 79:21). The method was linear between 0.3μg/g and 15μg/g for levofloxacin and ciprofloxacin with coefficient of correlation (r) ≥0.999. The limit of detection and the limit of quantification for levofloxacin were 0.06μg/g and 0.2μg/g and for ciprofloxacin were 0.04μg/g and 0.13μg/g, respectively. Average concentrations (±SD) of levofloxacin and ciprofloxacin obtained from patients tissue were 5.4±2.2μg/g and 3.9±1.5μg/g, respectively. Additionally, during validation procedure a novel, experimental design approach was applied for the robustness study. For evaluation of analytical method robustness, Plackett-Burman design was employed and for sample preparation method robustness Fractional Factorial design was used. The developed and validated method was successfully applied to examine prostate tissue samples obtained from patients enrolled into a clinical study. Up to now, there has been no other HPLC-ESI-MS/MS method reported for the simultaneous determination of levofloxacin and ciprofloxacin in human prostatic tissue. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Biotransformation of isoimperatorin by rat liver microsomes and its quantification by LC-MS/MS method.

    Science.gov (United States)

    Chen, Tian-Li; Zhang, You-Bo; Xu, Wei; Kang, Ting-Guo; Yang, Xiu-Wei

    2014-03-01

    The aim of the present research was to establish a comprehensive strategy to identify the metabolites of isoimperatorin after biotransformation with rat liver microsomes in vitro, and further describe metabolic kinetic characteristics of isoimperatorin and its main metabolites. Utilizing liquid chromatography with time of flight mass spectrometry (LC-TOF-MS), 18 metabolites (M 1-18) were characterized according to the typical fragment ions and literature data. Among them, M-2, 3, 5, 9, 10, and 15 were new compounds. To further verify structures of the metabolites, five main metabolites were obtained from the magnifying biotransformation incubation system, and their chemical structures were elucidated as 8-hydroxyoxypeucedanin (M-3), hydroxypeucedanin hydrate (M-4), E-5-(4-hydroxy-3-methyl-2-alkenyloxy)-psoralen (M-11), Z-5-(4-hydroxy-3-methyl-2-alkenyloxy)-psoralen (M-12), and oxypeucedanin (M-16) by various spectroscopy methods including IR, MS and NMR. A simple new liquid chromatography with triple quadrupole tandem mass spectrometry (LC-QqQ-MS) method was developed for the simultaneous determination of isoimperatorin and its main metabolites. The analysis was performed on a Diamonsil™ ODS C18 column with acetonitrile-water containing 0.1% formic acid as mobile phase. Total run time was 20.0 min. The results suggested that the method we exhibited was successfully applied for analysis of isoimperatorin and its metabolites. The study provides essential data for proposing metabolite pathway and further pharmacological study of isoimperatorin.

  7. Identification and quantitation of new glutamic acid derivatives in soy sauce by UPLC/MS/MS.

    Science.gov (United States)

    Frerot, Eric; Chen, Ting

    2013-10-01

    Glutamic acid is an abundant amino acid that lends a characteristic umami taste to foods. In fermented foods, glutamic acid can be found as a free amino acid formed by proteolysis or as a non-proteolytic derivative formed by microorganisms. The aim of the present study was to identify different structures of glutamic acid derivatives in a typical fermented protein-based food product, soy sauce. An acidic fraction was prepared with anion-exchange solid-phase extraction (SPE) and analyzed by UPLC/MS/MS and UPLC/TOF-MS. α-Glutamyl, γ-glutamyl, and pyroglutamyl dipeptides, as well as lactoyl amino acids, were identified in the acidic fraction of soy sauce. They were chemically synthesized for confirmation of their occurrence and quantified in the selected reaction monitoring (SRM) mode. Pyroglutamyl dipeptides accounted for 770 mg/kg of soy sauce, followed by lactoyl amino acids (135 mg/kg) and γ-glutamyl dipeptides (70 mg/kg). In addition, N-succinoylglutamic acid was identified for the first time in food as a minor compound in soy sauce (5 mg/kg).

  8. Laser Desorption Postionization for Imaging MS of Biological Material

    OpenAIRE

    Akhmetov, Artem; Moore, Jerry F.; Gasper, Gerald L.; Koin, Peter J.; Hanley, Luke

    2010-01-01

    Vacuum ultraviolet single photon ionization (VUV SPI) is a soft ionization technique that has the potential to address many of the limitations of MALDI for imaging MS. Laser desorption postionization (LDPI) employs VUV SPI for postionization and is experimentally analogous to a MALDI instrument with the addition of a pulsed VUV light source. This review discusses progress in LDPI-MS over the last decade, with an emphasis on imaging MS of bacterial biofilms, analytes whose high salt environmen...

  9. A novel study of screening and confirmation of modafinil, adrafinil and their metabolite modafinilic acid under EI-GC-MS and ESI-LC-MS-MS ionization

    Directory of Open Access Journals (Sweden)

    Dubey S

    2009-01-01

    Full Text Available Objective: Adrafinil and modafinil have received wide publicity and have become controversial in the sporting world when several athletes were discovered allegedly using these drugs as doping agents. By acknowledging the facts, the World Anti-Doping Agency (WADA banned these drugs in sports since 2004. The present study explores the possibility of differentiating adrafinil and modafinil and their major metabolites under electron impact ionization in gas chromatograph-mass spectrometer (GC-MSD and electrospray ionization in liquid chromatograph-mass spectrometer (LC-MS/MS by studying the fragmentation pattern of these drugs. Materials and Methods: Adrafinil, modafinil and their major metabolite, modafinilic acid were analyzed on EI-GC-MSD and ESI-LC-MS/MS using various individual parameters on both the instruments. The analytical technique and equipment used in the analysis were an Agilent 6890N GC with 5973 mass selective detector for the GC-MSD analysis and an Agilent 1100 HPLC with API-3200 Triple quadrupole mass spectrometer for the LC-MS/MS analysis. Validation of both methods was performed using six replicates at different concentrations. Result and Discussion: The results show that adrafinil, modafinil and their major metabolite modafinilic acid could be detected as a single artifact without differentiation under EI-GC-MSD analysis. However, all drugs could be detected and differentiated under ESI-LCMS/MS analysis without any artifaction. The GC-MSD analysis gives a single artifact for both the drugs without differentiation and thus can be used as a marker for screening purposes. Further, the Multiple Reaction Monitoring (MRM method developed under LC-MS/MS is fit for the purpose for confirmation of suspicious samples in routine sports testing and in forensic and clinical analysis.

  10. Survival and mortality rates among Danes with MS

    DEFF Research Database (Denmark)

    Brønnum-Hansen, H; Stenager, Egon; Hansen, Thomas;

    2006-01-01

    people with MS, representing more than 200,000 person-years of observation, have been analysed. Overall, mortality was almost three times higher and life expectancy 10 years less among people with MS than for the general population. However, excess mortality has declined significantly since 1950.......Long-term survival and trends in overall and cause-specific excess mortality among people with MS have been studied using the Danish Multiple Sclerosis Registry, which contains information about all Danish MS patients since the mid-20th Century. A total of 4254 deaths among approximately 10,000...

  11. Ethyl Esterification for MALDI-MS Analysis of Protein Glycosylation.

    Science.gov (United States)

    Reiding, Karli R; Lonardi, Emanuela; Hipgrave Ederveen, Agnes L; Wuhrer, Manfred

    2016-01-01

    Ethyl esterification is a technique for the chemical modification of sialylated glycans, leading to enhanced stability when performing matrix-assisted laser desorption/ionization (MALDI)-mass spectrometry (MS), as well as allowing the efficient detection of both sialylated and non-sialylated glycans in positive ion mode. In addition, the method shows specific reaction products for α2,3- and α2,6-linked sialic acids, leading to an MS distinguishable mass difference. Here, we describe the ethyl esterification protocol for 96 glycan samples, including enzymatic N-glycan release, the aforementioned ethyl esterification, glycan enrichment, MALDI target preparation, and the MS(/MS) measurement.

  12. Preprocessing and Analysis of LC-MS-Based Proteomic Data.

    Science.gov (United States)

    Tsai, Tsung-Heng; Wang, Minkun; Ressom, Habtom W

    2016-01-01

    Liquid chromatography coupled with mass spectrometry (LC-MS) has been widely used for profiling protein expression levels. This chapter is focused on LC-MS data preprocessing, which is a crucial step in the analysis of LC-MS based proteomics. We provide a high-level overview, highlight associated challenges, and present a step-by-step example for analysis of data from LC-MS based untargeted proteomic study. Furthermore, key procedures and relevant issues with the subsequent analysis by multiple reaction monitoring (MRM) are discussed.

  13. A new type of GC-MS with advanced capabilities

    Science.gov (United States)

    Fialkov, Alexander B.; Steiner, Urs; Jones, Larry; Amirav, Aviv

    2006-03-01

    We have combined the benefits of supersonic molecular beam interface and its related fly-through electron ionization (EI) ion source with the advanced features of the Varian 1200L gas chromatography-mass spectrometry (GC-MS) and mass spectrometry-mass spectrometry (MS-MS), resulting in a new and powerful GC-MS platform with record setting performance. Electron ionization of vibrationally cold molecules in the supersonic molecular beams (SMB) (cold EI) provided mass spectra with enhanced molecular ion, yet with good library search results and superior identification probabilities. We found that high GC column flow rates lower the elution temperature for any given compounds. This allows much larger molecules to elute at the maximum temperature of standard columns. We analyzed a mixture of heavy linear chain hydrocarbons all the way to C84H170 with a molecular weight of 1179.3 amu, using a 4 m 0.25 mm i.d. column and 32 ml/min He flow rate. Furthermore, we obtained a dominant molecular ion to all these compounds. The lower elution temperatures also greatly enhance the ability to analyze very thermally labile compounds such as carbamate pesticides. The experimental 1200 system is capable of triple quadrupole based MS-MS. We found that MS-MS on the molecular ion is much more effective than on fragment ions, and thus, the enhancement of the molecular ion directly improves the MS-MS sensitivity. Fast GC-MS analysis was also explored, based on very high column flow rate for fast splitless injections without affecting the sensitivity, and on the high system selectivity due to the combination of enhanced molecular ion and MS-MS. We demonstrate a few seconds long GC-MS-MS analysis of diazinon, spiked at 10 ng/g in a mixed fruit and vegetable extract. The feature of enhanced molecular ion provides significant enhancement in the detection sensitivity via SIM and RSIM on the molecular ion. While octafluoronaphthalene (OFN) detection limit of below 1 fg in SIM mode is shown, the

  14. MS Based Imaging of Barley Seed Development

    Institute of Scientific and Technical Information of China (English)

    Manuela Peukert; Andrea Matros; Hans-Peter Mock

    2012-01-01

    Spatially resolved analysis of metabolites and proteins is essential to model compartmentalized cellular processes in plants.Within recent years,tremendous progress has been made in MS based imaging (MSI) techniques,mostly MALDI MSI.The technology has been pioneered and is now widely applied in medicinal and pharmacological studies,and in recent years found its way into plant science (Kaspar et al.,2011; Peukert etal.,2012).We are interested in the elucidation of spatially resolved metabolic networks related to barley grain development.An understanding of developmentally and ecologically regulated processes affecting agronomical traits such as final grain weight,seed quality and stress tolerance is of outmost importance,as barley provides one of the staple foods.Barley also serves as a model plant for other cereals such as wheat.The presentation will introduce an untargeted MALDI MSI approach to the analysis of me-tabolite patterns during barley grain development.We analyzed longitudinal and cross sections from developing barley grains (3,7,10 and 14 days after pollination).In the presentation we will address spatial resolution,sensitivity and identification of unknown compounds will also be discussed.A major task is to connect the metabolite patterns to distinct cellular and physiological events.As an example,particular metabolite distributions indicative for nutrient transport into the developing endosperm will be shown.

  15. LC-ESI-MS/MS identification of polar lipids of two thermophilic Anoxybacillus bacteria containing a unique lipid pattern.

    Science.gov (United States)

    Rezanka, Tomáš; Kambourova, Margarita; Derekova, Anna; Kolouchová, Irena; Sigler, Karel

    2012-07-01

    Phospholipids and glycolipids from two recently described species belonging to the thermophilic genus Anoxybacillus were analyzed by liquid chromatography-electrospray tandem mass spectrometry (LC/ESI-MS/MS). Analysis of total lipids from the facultatively anaerobic A. bogrovensis on a HILIC (Hydrophilic Interaction LIquid Chromatography) column succeeded in separating diacyl- and plasmalogen phospholipids. The LC/ESI-MS/MS analysis of the strict aerobe A. rupiensis revealed the presence of different unique polar lipids, predominantly alanyl-, lysyl-, and glucosyl-phosphatidylglycerols and cardiolipins. Each of the classes of polar lipids was then analyzed by means of the ESI-MS/MS and more than 140 molecular species of six lipid classes from A. bogrovensis and nearly 200 molecular species of nine classes of polar lipids from A. rupiensis were identified. Five classes of unidentified polar lipids were detected in both strains. Plasmalogens were thus determined for the first time in a facultatively anaerobic bacterium, i.e. A. bogrovensis.

  16. Pyrolysis characteristic of tobacco stem studied by Py-GC/MS, TG-FTIR, and TG-MS

    Directory of Open Access Journals (Sweden)

    Bei Liu

    2013-02-01

    Full Text Available Pyrolysis characteristics and mechanism of tobacco stem were studied by pyrolysis coupled with gas chromatography/mass spectrometry (Py-GC/MS, thermogravimetric analyzer coupled with Fourier transform infrared spectrometry, and mass spectrometry (TG-FTIR and TG-MS techniques. The composition of evolved volatiles from fast pyrolysis of tobacco stem was determined by Py-GC/MS analysis, and the evolution patterns of the major products were investigated by TG-FTIR and TG-MS. Py-GC/MS data indicated that furfural and phenol were the major products in low temperature pyrolysis, and these were generated from depolymerization of cellulose. Indene and naphthalene were the major products in high temperature pyrolysis. TG-FTIR and TG-MS results showed that CO, CO2, phenols, aldehydes, and ketones were released between 167ºC and 500ºC; at temperatures >500ºC, CO and CO2 were the main gaseous products.

  17. Comparative GC/MS and LC/MS detection of hexabromocyclododecane (HBCD) in soil and water samples

    Energy Technology Data Exchange (ETDEWEB)

    Petersen, M.; Hamm, S. [Eurofins, Hamburg (Germany)]|[Gesellschaft fuer Arbeitswissenschaft e.V. (GfA), Dortmund (Germany); Schaefer, A. [Eurofins Analytik GmbH, Wiertz - Eggert - Joerissen, Hamburg (Germany); Esser, U. [GfA Constult GmbH, Muenster (Germany)

    2004-09-15

    Hexabromocyclododecane (HBCD) is a crucial additive flame retardant (FR) for FR Polystyrene insulation foams (both expandable (EPS) as well as extrudable polystyrene (XPS)), polystyrene masterbatches and textile FR coatings. The total consumption of HBCD within the European Union (EU) is estimated to be about 10,000 tons out of 16,700 worldwide per year. The technical HBCD product usually is a mixture of the three diastereoisomers {alpha}-, {beta}- and {gamma}-HBCD with the {gamma}- isomer as main component. Compared to other flame retardants only few data on HBCD levels in the environment have been published. Within this study a series of soil and water samples from HBCD processing plants was analysed by GC/MS (LRMS-EI). Besides GC/MS, also liquid chromatography coupled to mass spectrometry (LC/MS) is often used for HBCD detection in environmental samples. Whilst GC/MS only provides information about the total of the three HBCD isomers, LC/MS is able to selectively monitor and quantify the three components. On the other hand GC/MS usually has the advantage of a higher sensitivity. In order to verify the GC/MS results and to check the comparability to LC/MS analytical data, five soil and five water samples showing a wide range of HBCD concentrations were analysed by using both techniques. The comparative analyses by means of LC/MS confirmed the HBCD identification and quantification of the GC/MS. The differences between the total HBCD results of the GC/MS and the LC/MS analyses were less than 24%. The {gamma}- isomer proved to be the main HBCD diastereoisomer in the soil and water samples tested.

  18. MS/MS-Assisted Design of Sequence-Controlled Synthetic Polymers for Improved Reading of Encoded Information

    Science.gov (United States)

    Charles, Laurence; Cavallo, Gianni; Monnier, Valérie; Oswald, Laurence; Szweda, Roza; Lutz, Jean-François

    2016-12-01

    In order to improve their MS/MS sequencing, structure of sequence-controlled synthetic polymers can be optimized based on considerations regarding their fragmentation behavior in collision-induced dissociation conditions, as demonstrated here for two digitally encoded polymer families. In poly(triazole amide)s, the main dissociation route proceeded via cleavage of the amide bond in each monomer, hence allowing the chains to be safely sequenced. However, a competitive cleavage of an ether bond in a tri(ethylene glycol) spacer placed between each coding moiety complicated MS/MS spectra while not bringing new structural information. Changing the tri(ethylene glycol) spacer to an alkyl group of the same size allowed this unwanted fragmentation pathway to be avoided, hence greatly simplifying the MS/MS reading step for such undecyl-based poly(triazole amide)s. In poly(alkoxyamine phosphodiester)s, a single dissociation pathway was achieved with repeating units containing an alkoxyamine linkage, which, by very low dissociation energy, made any other chemical bonds MS/MS-silent. Structure of these polymers was further tailored to enhance the stability of those precursor ions with a negatively charged phosphate group per monomer in order to improve their MS/MS readability. Increasing the size of both the alkyl coding moiety and the nitroxide spacer allowed sufficient distance between phosphate groups for all of them to be deprotonated simultaneously. Because the charge state of product ions increased with their polymerization degree, MS/MS spectra typically exhibited groups of fragments at one or the other side of the precursor ion depending on the original α or ω end-group they contain, allowing sequence reconstruction in a straightforward manner.

  19. MS/MS-Assisted Design of Sequence-Controlled Synthetic Polymers for Improved Reading of Encoded Information

    Science.gov (United States)

    Charles, Laurence; Cavallo, Gianni; Monnier, Valérie; Oswald, Laurence; Szweda, Roza; Lutz, Jean-François

    2017-06-01

    In order to improve their MS/MS sequencing, structure of sequence-controlled synthetic polymers can be optimized based on considerations regarding their fragmentation behavior in collision-induced dissociation conditions, as demonstrated here for two digitally encoded polymer families. In poly(triazole amide)s, the main dissociation route proceeded via cleavage of the amide bond in each monomer, hence allowing the chains to be safely sequenced. However, a competitive cleavage of an ether bond in a tri(ethylene glycol) spacer placed between each coding moiety complicated MS/MS spectra while not bringing new structural information. Changing the tri(ethylene glycol) spacer to an alkyl group of the same size allowed this unwanted fragmentation pathway to be avoided, hence greatly simplifying the MS/MS reading step for such undecyl-based poly(triazole amide)s. In poly(alkoxyamine phosphodiester)s, a single dissociation pathway was achieved with repeating units containing an alkoxyamine linkage, which, by very low dissociation energy, made any other chemical bonds MS/MS-silent. Structure of these polymers was further tailored to enhance the stability of those precursor ions with a negatively charged phosphate group per monomer in order to improve their MS/MS readability. Increasing the size of both the alkyl coding moiety and the nitroxide spacer allowed sufficient distance between phosphate groups for all of them to be deprotonated simultaneously. Because the charge state of product ions increased with their polymerization degree, MS/MS spectra typically exhibited groups of fragments at one or the other side of the precursor ion depending on the original α or ω end-group they contain, allowing sequence reconstruction in a straightforward manner. [Figure not available: see fulltext.

  20. Sensitive and Rapid UHPLC-MS/MS for the Analysis of Tomato Phenolics in Human Biological Samples

    Directory of Open Access Journals (Sweden)

    Miriam Martínez-Huélamo

    2015-11-01

    Full Text Available An UHPLC-MS/MS method for the quantification of tomato phenolic metabolites in human fluids was optimized and validated, and then applied in a pilot dietary intervention study with healthy volunteers. A 5-fold gain in speed (3.5 min of total run; 7-fold increase in MS sensitivity and 2-fold greater efficiency (50% peak width reduction were observed when comparing the proposed method with the reference-quality HPLC-MS/MS system, whose assay performance has been previously documented. The UHPLC-MS/MS method led to an overall improvement in the limits of detection (LOD and quantification (LOQ for all the phenolic compounds studied. The recoveries ranged between 68% and 100% in urine and 61% and 100% in plasma. The accuracy; intra- and interday precision; and stability met with the acceptance criteria of the AOAC International norms. Due to the improvements in the analytical method; the total phenolic metabolites detected in plasma and urine in the pilot intervention study were 3 times higher than those detected by HPLC-MS/MS. Comparing with traditional methods; which require longer time of analysis; the methodology described is suitable for the analysis of phenolic compounds in a large number of plasma and urine samples in a reduced time frame.

  1. [Multiresidue method for determination of pesticides in fruits and vegetables by GC/MS (SCAN) and LC/MS (SIM)].

    Science.gov (United States)

    Kakimoto, Yoshihisa; Naetoko, Yoshitaka; Iwasaki, Yoshinari; Nakamura, Shigeru; Tatsuguchi, Hisako

    2005-08-01

    A rapid multiresidue method has been developed for determination of many pesticides in fruits and vegetables using GC/MS and LC/MS. The method of analysis was the same as that reported by Kakimoto et al. in 2003 except for the use of LC/MS. Good recoveries in the range of 70-120% were obtained for 70 (32 by GC/MS, 38 by LC/MS) of 113 pesticides spiked at 0.1 microg/g into fruits and vegetables. For screening purposes, the method could be appiled to 82 pesticides. Considering the report by Kakimoto et al. in 2004, 177 pesticides were suitable for screening by this method. The limits of detection were 0.001-0.015 microg/g (by GC/MS) and < 0.001-0.010 microg/g (by LC/MS). The calibration curves were linear for most pesticides, with correlation coefficients of 0.976-1.000 (by GC/MS) and 0.968-1.000 (by LC/MS). The values obtained for fruits and vegetables naturally contaminated with pesticides by this method were nearly equal to those by the official method.

  2. High-resolution MS, MS/MS, and UV database of fungal secondary metabolites as a dereplication protocol for bioactive natural products.

    Science.gov (United States)

    El-Elimat, Tamam; Figueroa, Mario; Ehrmann, Brandie M; Cech, Nadja B; Pearce, Cedric J; Oberlies, Nicholas H

    2013-09-27

    A major problem in the discovery of new biologically active compounds from natural products is the reisolation of known compounds. Such reisolations waste time and resources, distracting chemists from more promising leads. To address this problem, dereplication strategies are needed that enable crude extracts to be screened for the presence of known compounds before isolation efforts are initiated. In a project to identify anticancer drug leads from filamentous fungi, a significant dereplication challenge arises, as the taxonomy of the source materials is rarely known, and, thus, the literature cannot be probed to identify likely known compounds. An ultraperformance liquid chromatography-photodiode array-high-resolution tandem mass spectrometric (UPLC-PDA-HRMS-MS/MS) method was developed for dereplication of fungal secondary metabolites in crude culture extracts. A database was constructed by recording HRMS and MS/MS spectra of fungal metabolites, utilizing both positive- and negative-ionization modes. Additional details, such as UV-absorption maxima and retention times, were also recorded. Small-scale cultures that showed cytotoxic activities were dereplicated before engaging in the scale-up or purification processes. Using these methods, approximately 50% of the cytotoxic extracts could be eliminated from further study after the confident identification of known compounds. The specific attributes of this dereplication methodology include a focus on bioactive secondary metabolites from fungi, the use of a 10 min chromatographic method, and the inclusion of both HRMS and MS/MS data.

  3. KERNEL IDEALS AND CONGRUENCES ON MS-ALGEBRAS

    Institute of Scientific and Technical Information of China (English)

    Luo Congwen; Zeng Yanlu

    2006-01-01

    In this article, the authors describe the largest congruence induced by a kernel ideal of an MS-algebra and characterize those MS-algebras on which all the congruences are in a one-to-one correspondence with the kernel ideals.

  4. The Non- and Semiparametric Analysis of MS Models : Some Applications

    NARCIS (Netherlands)

    Li, Y.; Donkers, A.C.D.; Melenberg, B.

    2006-01-01

    This paper illustrates how to compare different microscopic simulation (MS) models and how to compare a MS model with real data in case the parameters of interest are estimated non- or semiparametrically.As examples we investigate the marginal single-period probability density function of stock retu

  5. Fluctuations of MS births and UV-light exposure

    NARCIS (Netherlands)

    Verheul, F.; Smolders, J.; Trojano, M.; Lepore, V.; Zwanikken, C.; Amato, M. P.; Grand'Maison, F.; Butzkueven, H.; Marrosu, M.; Duquette, P.; Comi, G.; Izquierdo, G.; Grammond, P.; Lus, G.; Petersen, T.; Bergamaschi, R.; Giuliani, G.; Boz, C.; Coniglio, G.; Van Pesch, V.; Lechner-Scott, J.; Cavalla, P.; Granella, F.; Avolio, C.; Fiol, M.; Poehlau, D.; Saladino, M. L.; Gallo, P.; Deri, N.; Oleschko Arruda, W.; Paine, M.; Ferro, M.; Barnett, M.; Cabrera-Gomez, J. A.; Slee, M.; Moore, F.; Shaw, C.; Petkovska-Boskova, T.; Rutherford, M.; Engelsen, O.; Damoiseaux, J.; Hupperts, R.

    2013-01-01

    Background Patients with multiple sclerosis (MS) are more frequently born in spring when compared to autumn. Fluctuation of UV-light has been hypothesized to drive this phenomenon. Aim To assess the correlation between fluctuation of sunlight and birth season in persons with MS. Methods For this rec

  6. The identification of anaerobic bacteria using MALDI-TOF MS

    NARCIS (Netherlands)

    Veloo, A. C. M.; Welling, G. W.; Degener, J. E.

    2011-01-01

    Matrix Assisted Laser Desorption and Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF MS) has gained more and more popularity for the identification of bacteria. Several studies show that bacterial diagnosticis is being revolutionized by the application of MALDI-TOF MS. For anaerobic bacteria,

  7. Quantitative performance of a quadrupole-orbitrap-MS in targeted LC-MS determinations of small molecules.

    Science.gov (United States)

    Grund, Baptiste; Marvin, Laure; Rochat, Bertrand

    2016-05-30

    High-resolution mass spectrometry (HRMS) has been associated with qualitative and research analysis and QQQ-MS with quantitative and routine analysis. This view is now challenged and for this reason, we have evaluated the quantitative LC-MS performance of a new high-resolution mass spectrometer (HRMS), a Q-orbitrap-MS, and compared the results obtained with a recent triple-quadrupole MS (QQQ-MS). High-resolution full-scan (HR-FS) and MS/MS acquisitions have been tested with real plasma extracts or pure standards. Limits of detection, dynamic range, mass accuracy and false positive or false negative detections have been determined or investigated with protease inhibitors, tyrosine kinase inhibitors, steroids and metanephrines. Our quantitative results show that today's available HRMS are reliable and sensitive quantitative instruments and comparable to QQQ-MS quantitative performance. Taking into account their versatility, user-friendliness and robustness, we believe that HRMS should be seen more and more as key instruments in quantitative LC-MS analyses. In this scenario, most targeted LC-HRMS analyses should be performed by HR-FS recording virtually "all" ions. In addition to absolute quantifications, HR-FS will allow the relative quantifications of hundreds of metabolites in plasma revealing individual's metabolome and exposome. This phenotyping of known metabolites should promote HRMS in clinical environment. A few other LC-HRMS analyses should be performed in single-ion-monitoring or MS/MS mode when increased sensitivity and/or detection selectivity will be necessary.

  8. Determination of Scopolamine in Human Saliva Using Solid Phase Extraction and LC/MS/MS

    Science.gov (United States)

    Wang, Zuwei; Vaksman, Zalman; Boyd, Jason; Putcha, Lakshmi

    2007-01-01

    Purpose: Scopolamine is the preferred treatment for motion sickness during space flight because of its quick onset of action, short half-life and favorable side-effect profile. The dose administered depends on the mode of administration and usually ranges between 0.1 and 0.8 mg. Such small doses make it difficult to detect concentrations of scopolamine in biological fluids by using conventional HPLC methods. To measure scopolamine in saliva and thereby to evaluate the pharmacokinetics of scopolamine, we developed an LC/MS/MS method using off-line solid phase extraction. Method: Samples (0.5mL) were loaded onto Waters Oasis HLB co-polymer cartridges (10 mg, 1 mL) and eluted with 0.5 mL methanol without evaporation and reconstitution. HPLC separation of the eluted sample was performed using an Agilent Zorbax SB-CN column (50 x 2.1 mm) at a flow rate of 0.2 mL/min for 4 minutes. The mobile phase for separation was 90:10 (v/v) methanol: ammonium acetate (2 mM) in water, pH 5.0 +/- 0.1. Concentrations of scopolamine were determined using a Micromass Quattro Micro(TM) mass spectrometer with electrospray ionization (ESI). ESI mass spectra were acquired in positive ion mode with multiple reaction monitoring for the determination of scopolamine m/z = 304.2 yields 138.1 and internal standard (IS) hyoscyamine m/z = 290.2 yields 124.1. Results: The method is rapid, reproducible, specific and has the following parameters: scopolamine and the IS are eluted at 1.7 and 3.2 min respectively. The linear range is 50-5000 pg/mL for scopolamine in saliva with correlation coefficients > 0.99 with a CV saliva. Conclusion: Solid phase extraction allows more rapid sample preparation and greater precision than liquid extraction. Furthermore, we increased the sensitivity and specificity by adjusting the LC mobile phase and using an MS/MS detector.

  9. Organization of GC/MS and LC/MS metabolomics data into chemical libraries

    Directory of Open Access Journals (Sweden)

    DeHaven Corey D

    2010-10-01

    Full Text Available Abstract Background Metabolomics experiments involve generating and comparing small molecule (metabolite profiles from complex mixture samples to identify those metabolites that are modulated in altered states (e.g., disease, drug treatment, toxin exposure. One non-targeted metabolomics approach attempts to identify and interrogate all small molecules in a sample using GC or LC separation followed by MS or MSn detection. Analysis of the resulting large, multifaceted data sets to rapidly and accurately identify the metabolites is a challenging task that relies on the availability of chemical libraries of metabolite spectral signatures. A method for analyzing spectrometry data to identify and Quantify Individual Components in a Sample, (QUICS, enables generation of chemical library entries from known standards and, importantly, from unknown metabolites present in experimental samples but without a corresponding library entry. This method accounts for all ions in a sample spectrum, performs library matches, and allows review of the data to quality check library entries. The QUICS method identifies ions related to any given metabolite by correlating ion data across the complete set of experimental samples, thus revealing subtle spectral trends that may not be evident when viewing individual samples and are likely to be indicative of the presence of one or more otherwise obscured metabolites. Results LC-MS/MS or GC-MS data from 33 liver samples were analyzed simultaneously which exploited the inherent biological diversity of the samples and the largely non-covariant chemical nature of the metabolites when viewed over multiple samples. Ions were partitioned by both retention time (RT and covariance which grouped ions from a single common underlying metabolite. This approach benefitted from using mass, time and intensity data in aggregate over the entire sample set to reject outliers and noise thereby producing higher quality chemical identities. The

  10. Fatal cytisine intoxication and analysis of biological samples with LC-MS/MS.

    Science.gov (United States)

    Musshoff, F; Madea, B

    2009-04-15

    We report about a fatal cytisine intoxication in a 20-year-old man who, according to his mother, had drunken tea prepared from plant material of Laburnum anagyroides with the toxic pyridine-like alkaloid as ingredient, which exhibits pharmacological effects similar to nicotine. Using a liquid chromatographic-mass spectrometric (LC-MS) procedure cytisine was quantified in post-mortem specimens. By exclusion of other causes of death an intoxication was determined as the cause of death with respiratory failure as the pathophysiological mechanism.

  11. UPLC-MS/MS determination of florfenicol and florfenicol amine antimicrobial residues in tilapia muscle.

    Science.gov (United States)

    Orlando, Eduardo Adilson; Costa Roque, Aline Gabriela; Losekann, Marcos Eliseu; Colnaghi Simionato, Ana Valéria

    2016-11-01

    Despite the benefits to fish farmers, the use of antimicrobials in aquaculture has concerned consumers and competent authorities. The indiscriminate use of such substances promotes the emergence of resistant microorganisms, decreases the effectiveness of treatments, and causes possible toxic effects in humans. In Brazil, florfenicol is the only antimicrobial registered for use in aquaculture and is often used in tilapia in cage creation. Thus, this study aimed to develop a method for determination of florfenicol residues and its metabolite florfenicol amine in tilapia fillet by UPLC-MS/MS. Analytes were extracted with ethyl acetate, followed by liquid-liquid partition clean-up with hexane and SPE. The sorbents C18, phenyl and HLB-Oasis were evaluated by SPE. Phenyl sorbent showed the best results, and the extraction conditions were optimized in the sample matrix with fractional factorial design 2(4-1). The analytes were separated on a C18 chromatographic column (50×2.1mm×1.7μm) using water (A) and acetonitrile (B) as mobile phase at a flow rate of 0.3mLmin(-1) with a linear gradient (in% B): 0-2.0min: 20%; 2.0-2.5min: increase to 90%; 2.5-3.5min: 90%; 3.0-3.5min: decrease to 20%; 4.0-5.0min: 20%. The analytes were monitored in a MS/MS triple quadrupole system by MRM mode with transitions at m/z 356.1>336.1 (florfenicol) and m/z 248.1>130.1 (florfenicol amine). The optimized method was validated obtaining LOQ values of 3 and 25ngg(-1) for florfenicol and florfenicol amine, respectively, precision between 20 and 36%, absolute extraction efficiency between 38 and 80%, and adequate linearity. The method was applied to samples intended for human consumption, and within the 15 evaluated samples, only one showed florfenicol residue at 30ngg(-1), which is below the maximum residue limit established in Brazil.

  12. Coumarin tags for analysis of peptides by MALDI-TOF MS and MS/MS. 2. Alexa Fluor 350 tag for increased peptide and protein Identification by LC-MALDI-TOF/TOF MS.

    Science.gov (United States)

    Pashkova, Anna; Chen, Hsuan-Shen; Rejtar, Tomas; Zang, Xin; Giese, Roger; Andreev, Victor; Moskovets, Eugene; Karger, Barry L

    2005-04-01

    The goal of this study was the development of N-terminal tags to improve peptide identification using high-throughput MALDI-TOF/TOF MS. Part 1 of the study was focused on the influence of derivatization on the intensities of MALDI-TOF MS signals of peptides. In part 2, various derivatization approaches for the improvement of peptide fragmentation efficiency in MALDI-TOF/TOF MS are explored. We demonstrate that permanent cation tags, while significantly improving signal intensity in the MS mode, lead to severe suppression of MS/MS fragmentation, making these tags unsuitable for high-throughput MALDI-TOF/TOF MS analysis. In the present work, it was found that labeling with Alexa Fluor 350, a coumarin tag containing a sulfo group, along with guanidation of epsilon-amino groups of Lys, could enhance unimolecular fragmentation of peptides with the formation of a high-intensity y-ion series, while the peptide intensities in the MS mode were not severely affected. LC-MALDI-TOF/TOF MS analysis of tryptic peptides from the SCX fractions of an E. coli lysate revealed improved peptide scores, a doubling of the total number of peptides, and a 30% increase in the number of proteins identified, as a result of labeling. Furthermore, by combining the data from native and labeled samples, confidence in correct identification was increased, as many proteins were identified by different peptides in the native and labeled data sets. Additionally, derivatization was found not to impair chromatographic behavior of peptides. All these factors suggest that labeling with Alexa Fluor 350 is a promising approach to the high-throughput LC-MALDI-TOF/TOF MS analysis of proteomic samples.

  13. The determination of budesonide and fluticasone in human sputum samples collected from COPD patients using LC-MS/MS

    NARCIS (Netherlands)

    Buscher, B.A.P.; Jägfeldt, H.; Sandman, H.; Brust-van Schaik, R.; Schaik, F. van; Brüll, L.P.

    2012-01-01

    A bioanalytical method for the quantitative determination of budesonide and fluticasone in human sputum was developed. Sputolysin ® Reagent was added to the sputum samples. After incubation (37°C; 60-70min under shaking) and automated solid phase extraction the extracts were analysed using LC-MS/MS.

  14. Rapid analyses of proteomes and interactomes using an integrated solid-phase extraction-liquid chromatography-MS/ms system

    NARCIS (Netherlands)

    Binai, Nadine A.; Marino, Fabio; Soendergaard, Peter; Bache, Nicolai; Mohammed, Shabaz; Heck, Albert J R

    2015-01-01

    Here, we explore applications of a LC system using disposable solid-phase extraction (SPE) cartridges and very short LC-MS/MS gradients that allows for rapid analyses in less than 10 min analysis time. The setup consists of an autosampler harboring two sets of 96 STAGE tips that function as precolum

  15. Quantitative analysis of Tenecteplase in rat plasma samples using LC-MS/MS as an alternative for ELISA

    NARCIS (Netherlands)

    Buscher, B.A.P.; Gerritsen, H.; Schöll, I. van; Cnubben, N.H.P.; Brüll, L.P.

    2007-01-01

    An LC-MS/MS method has been developed for the quantitative determination of a protein drug (Tenecteplase; MW 58,777 Da) in rat plasma. The protein was digested with trypsin without prior clean-up of the plasma sample, without the use of a label nor internal standard. A limited validation was perform

  16. Current status and future developments of LC-MS/MS in clinical chemistry for quantification of biogenic amines

    NARCIS (Netherlands)

    de Jong, Wilhelmina H. A.; de Vries, Elisabeth G. E.; Kema, Ido P.

    Liquid chromatography-tandem mass spectrometry (LC-MS/MS) is rapidly gaining ground in special clinical chemistry laboratories. It significantly increases the analytic potential in clinical chemistry, especially in the field of low molecular weight biomarker analysis. This review overviews current

  17. Quantification of amikacin and kanamycin in serum using a simple and validated LC-MS/MS method

    NARCIS (Netherlands)

    Dijkstra, Jacob A.; Sturkenboom, Marieke G. G.; van Hateren, Kai; Koster, Remco A.; Greijdanus, Ben; Alffenaar, Jan-Willem C.

    2014-01-01

    Background: Amikacin and kanamycin are frequently used in the treatment of multidrug-resistant TB. The current commercially available immunoassay is unable to analyze kanamycin and trough levels of amikacin. The objective was therefore to develop a LC-MS/MS method for the quantification of amikacin

  18. Quantitative analysis of Tenecteplase in rat plasma samples using LC-MS/MS as an alternative for ELISA

    NARCIS (Netherlands)

    Buscher, B.A.P.; Gerritsen, H.; Schöll, I. van; Cnubben, N.H.P.; Brüll, L.P.

    2007-01-01

    An LC-MS/MS method has been developed for the quantitative determination of a protein drug (Tenecteplase; MW 58,777 Da) in rat plasma. The protein was digested with trypsin without prior clean-up of the plasma sample, without the use of a label nor internal standard. A limited validation was perform

  19. Simultaneous Determination of Structurally Diverse Compounds in Different Fangchi Species by UHPLC-DAD and UHPLC-ESI-MS/MS

    Directory of Open Access Journals (Sweden)

    Kang Ro Lee

    2013-05-01

    Full Text Available Two bisbenzylisoquinoline alkaloids, two morphine alkaloids, one aporphine alkaloid, syringaresinol and aristolochic acid І were selected as marker compounds and simultaneously analyzed using an ultra-high pressure liquid chromatography-diode array detection (UHPLC-DAD method. These marker compounds were used for the quality control of Fangchi species of different origins, including Sinomenium acutum, Stephania tetrandra, Cocculus trilobus and Aristolochia fangchi. A reversed-phase UHPLC-DAD method was developed and validated for the simultaneous quantification of structurally diverse markers in different Fangchi species. In addition, an UHPLC-electrospray ionization tandem mass spectrometry (ESI-MS/MS method was used for marker identification in Fangchi species, which provided diagnostic MS/MS spectral patterns that were dependent upon the marker structures. The UHPLC-MS/MS data were used to confirm and complement the UHPLC-DAD quality evaluation results. Additionally, magnoflorine and syringaresinol were observed for the first time in S. tetrandra and C. trilobus, respectively. Twenty different Fangchi species samples were analyzed for aristolochic acid I, syringaresinol and the alkaloids using the UHPLC-DAD and MS/MS method. Based on the levels of markers and principal component analysis (PCA, this method allowed for the clear classification of the samples into four different groups representing samples originating from the four species.

  20. Male Sex Is Independently Associated with Faster Disability Accumulation in Relapse-Onset MS but Not in Primary Progressive MS.

    Directory of Open Access Journals (Sweden)

    Karen Ann Ribbons

    Full Text Available Multiple Sclerosis is more common in women than men and females have more relapses than men. In a large international cohort we have evaluated the effect of gender on disability accumulation and disease progression to determine if male MS patients have a worse clinical outcome than females.Using the MSBase Registry, data from 15,826 MS patients from 25 countries was analysed. Changes in the severity of MS (EDSS were compared between sexes using a repeated measures analysis in generalised linear mixed models. Kaplan-Meier analysis was used to test for sex difference in the time to reach EDSS milestones 3 and 6 and the secondary progressive MS.In relapse onset MS patients (n = 14,453, males progressed significantly faster in their EDSS than females (0.133 vs 0.112 per year, P<0.001,. Females had a reduced risk of secondary progressive MS (HR (95% CI = 0.77 (0.67 to 0.90 P = 0.001. In primary progressive MS (n = 1,373, there was a significant increase in EDSS over time in males and females (P<0.001 but there was no significant sex effect on the annualized rate of EDSS change.Among registrants of MSBase, male relapse-onset patients accumulate disability faster than female patients. In contrast, the rate of disability accumulation between male and female patients with primary progressive MS is similar.

  1. Application of LC/MS/MS Techniques to Development of US EPA Standardized Methods for Chemicals of Emerging Concern

    Science.gov (United States)

    This presentation will describe the U.S. EPA’s drinking water and ambient water method development program in relation to the process employed and the typical challenges encountered in developing standardized LC/MS/MS methods for chemicals of emerging concern. The EPA&rsquo...

  2. Metabolomic and elemental analysis of camel and bovine urine by GC-MS and ICP-MS.

    Science.gov (United States)

    Ahamad, Syed Rizwan; Alhaider, Abdul Qader; Raish, Mohammad; Shakeel, Faiyaz

    2017-01-01

    Recent studies from the author's laboratory indicated that camel urine possesses antiplatelet activity and anti-cancer activity which is not present in bovine urine. The objective of this study is to compare the volatile and elemental components of bovine and camel urine using GC-MS and ICP-MS analysis. We are interested to know the component that performs these biological activities. The freeze dried urine was dissolved in dichloromethane and then derivatization process followed by using BSTFA for GC-MS analysis. Thirty different compounds were analyzed by the derivatization process in full scan mode. For ICP-MS analysis twenty eight important elements were analyzed in both bovine and camel urine. The results of GC-MS and ICP-MS analysis showed marked difference in the urinary metabolites. GC-MS evaluation of camel urine finds a lot of products of metabolism like benzene propanoic acid derivatives, fatty acid derivatives, amino acid derivatives, sugars, prostaglandins and canavanine. Several research reports reveal the metabolomics studies on camel urine but none of them completely reported the pharmacology related metabolomics. The present data of GC-MS suggest and support the previous studies and activities related to camel urine.

  3. Detecting pM concentrations of prostaglandins in cell culture supernatants by capillary SCX-LC-MS/MS

    DEFF Research Database (Denmark)

    Dahl, Sandra Rinne; Kleiveland, Charlotte Ramstad; Kassem, Moustapha

    2008-01-01

    A highly sensitive, improved online strong cation exchange (SCX)--RP capillary liquid chromatographic (cLC) method with IT mass spectrometric (IT-MS/MS) detection for the simultaneous determination of prostaglandin (PG)A(1), PGD(2), PGE(1), PGE(2), PGF(2alpha), 8-iso-(8i)PGF(2alpha), 6-keto-(6k)P...

  4. Simultaneous determination of structurally diverse compounds in different Fangchi species by UHPLC-DAD and UHPLC-ESI-MS/MS.

    Science.gov (United States)

    Sim, Hee-Jung; Kim, Ji Hee; Lee, Kang Ro; Hong, Jongki

    2013-05-07

    Two bisbenzylisoquinoline alkaloids, two morphine alkaloids, one aporphine alkaloid, syringaresinol and aristolochic acid І were selected as marker compounds and simultaneously analyzed using an ultra-high pressure liquid chromatography-diode array detection (UHPLC-DAD) method. These marker compounds were used for the quality control of Fangchi species of different origins, including Sinomenium acutum, Stephania tetrandra, Cocculus trilobus and Aristolochia fangchi. A reversed-phase UHPLC-DAD method was developed and validated for the simultaneous quantification of structurally diverse markers in different Fangchi species. In addition, an UHPLC-electrospray ionization tandem mass spectrometry (ESI-MS/MS) method was used for marker identification in Fangchi species, which provided diagnostic MS/MS spectral patterns that were dependent upon the marker structures. The UHPLC-MS/MS data were used to confirm and complement the UHPLC-DAD quality evaluation results. Additionally, magnoflorine and syringaresinol were observed for the first time in S. tetrandra and C. trilobus, respectively. Twenty different Fangchi species samples were analyzed for aristolochic acid I, syringaresinol and the alkaloids using the UHPLC-DAD and MS/MS method. Based on the levels of markers and principal component analysis (PCA), this method allowed for the clear classification of the samples into four different groups representing samples originating from the four species.

  5. Ms.ing the Free Press: The Advertising and Editorial Content of "Ms." Magazine, 1972-1992.

    Science.gov (United States)

    McKinnon, Lori Melton

    1994-01-01

    Uses content analysis to show that, although "Ms." magazine sometimes compromised its promise to be a mass-mediated forum for feminist debate, its current format (ad-free, to do away with conflicts experienced between editors' ideology and advertisers' wishes) has allowed "Ms." to present a renewed vision of feminism. (SR)

  6. Matrix effects break the LC behavior rule for analytes in LC-MS/MS analysis of biological samples

    Science.gov (United States)

    High-performance liquid chromatography (HPLC) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) are generally accepted as the preferred techniques for detecting and quantitating analytes of interest in biological matrices on the basis of the rule that one chemical compound yields one LC-...

  7. QUANTIFICATION OF 2,4-D ON SOLID-PHASE EXPOSURE SAMPLING MEDIA BY LC/MS/MS

    Science.gov (United States)

    Three types of solid phase chemical exposure sampling media: cellulose, polyurethane foam (PUF) and XAD-2, were analyzed for 2,4-D and the amine salts of 2,4-D. Individual samples were extracted into acidified methanol and the extracts were analyzed via LC/MS/MS using electrospra...

  8. Top-down proteomic identification of protein biomarkers of food-borne pathogens using MALDI-TOF-TOF-MS/MS

    Science.gov (United States)

    This chapter describes a step-by-step protocol and discussion of top-down proteomic identification of protein biomarkers of food-borne pathogens using matrix-assisted laser desorption/ionization tandem time-of-flight mass spectrometry (MALDI-TOF-TOF-MS/MS) and web-based software developed in the Pro...

  9. Determination and pharmacokinetic study of pirfenidone in rat plasma by UPLC-MS/MS.

    Science.gov (United States)

    Sun, Wei; Jiang, Zhe-li; Zhou, Lei; Chen, Rui-min; Wang, Zhe; Li, Wan-shu; Jiang, Shuo-min; Hu, Guo-xin; Chen, Rui-jie

    2015-02-15

    A rapid, sensitive and selective ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) was developed and validated for the determination and pharmacokinetic investigation of pirfenidone in rat plasma. Sample preparation was accomplished through a simple one-step deproteinization procedure with 0.2 mL of acetonitrile to a 0.1 mL plasma sample. Plasma samples were separated by UPLC on an Acquity UPLC BEH C18 column using a mobile phase consisting of acetonitrile-0.1% formic acid in water with gradient elution. The total run time was 3.0 min and the elution of pirfenidone was at 1.39 min. The detection was performed on a triple quadrupole tandem mass spectrometer in the multiple reaction-monitoring (MRM) mode using the respective transitions m/z 186.2→92.1 for pirfenidone and m/z 237.1→194.2 for carbamazepine (IS), respectively. The calibration curve was linear over the range of 5-2000 ng/mL with a lower limit of quantitation (LLOQ) of 5 ng/mL. Mean recovery of pirfenidone in plasma was in the range of 80.4-84.3%. Intra-day and inter-day precision were both pirfenidone in rats.

  10. Determination of raloxifene hydrochloride in human urine by LC-MS-MS

    Directory of Open Access Journals (Sweden)

    K. Tharpa

    2009-09-01

    Full Text Available A sensitive and selective liquid chromatographic-tandem mass spectrometric (LC-MS-MS method was developed to determine raloxifene hydrochloride (RLX in human urine. After a solid-phase extraction with SPE cartridge, the urine sample was analyzed on a C18 column (Symmetry 3.5μm; 50 mm4.6 mm i.d interfaced with a triple quadruple tandem mass spectrometer. A positive electrospray ionization was employed as the ionization source. The mobile phase consisted of ammonium acetate (pH 4.0–acetonitrile (60:40, v/v.The method was linear over a concentration range of 20–1000 ng mL-1. The lower limit of quantitation was 20 ng mL-1. The intra-day and inter-day relative standard deviation across three validation runs over the entire concentration range was <10.5%. The accuracy determined at three concentrations (50, 500 and 850 ng mL-1 RLX was within ±0.84% in terms of relative errors.

  11. Detection of non-sterol isoprenoids by HPLC-MS/MS

    Science.gov (United States)

    Henneman, Linda; van Cruchten, Arno G.; Denis, Simone W.; Amolins, Michael W.; Placzek, Andrew T.; Gibbs, Richard A.; Kulik, Willem; Waterham, Hans R.

    2012-01-01

    Isoprenoids constitute an important class of biomolecules that participate in many different cellular processes. Most available detection methods only allow the identification of one or two specific non-sterol isoprenoid intermediates following radioactive or fluorescent labeling. We here report a rapid, non-radioactive and sensitive procedure for the simultaneous detection and quantification of the 8 main non-sterol intermediates of the isoprenoid biosynthesis pathway by means of tandem mass spectrometry. Intermediates were analyzed by HPLC-MS/MS in the multiple reaction monitoring mode using a silica-based C18 HPLC column. For quantification, their stable-isotope-labeled analogues were used as internal standards. HepG2 cells were used to validate the method. Mevalonate, phosphomevalonate and the 6 subsequent isoprenoid-pyrophosphates were readily determined with detection limits ranging from 0.03 to 1.0 μmol/L. The intra- and interassay variations for HepG2 cell homogenates supplemented with isoprenoid intermediates were 3.6–10.9% and 4.4–11.9%, respectively. Under normal culturing conditions, isoprenoid intermediates in HepG2 cells were below detection limits. However, incubation of the cells with pamidronate, an inhibitor of farnesyl pyrophosphate synthase, resulted in increased levels of MVA, IPP/DMAPP and GPP. This method will be suitable to measure profiles of isoprenoid intermediates in cells with compromised isoprenoid biosynthesis, and to determine the specificity of potential inhibitors of the pathway. PMID:18782552

  12. DETERMINATION OF COCAINE AND BENZOYLECGONINE IN BIOLOGICAL MATRICES BY HPLC AND LC-MS/MS.

    Directory of Open Access Journals (Sweden)

    Zinar Pinar GUMUS

    2016-10-01

    Full Text Available Cocaine is a powerfully addictive illicit drug. Cocaine abuse and addiction continue to increase in the world. Most analytical tests for the detection of cocaine use include the analysis of the metabolite, benzoylecgonine, in the urine. Benzoylecgonine is a major urinary metabolite of cocaine. Generally, the most common biologic matrices used for the analysis of cocaine contain the urine and blood however saliva was also added as a matrix in this study. Practical, quick, reliable, precise and accurate, reproducible analytical methods have been developed and validated for cocaine and benzoylecgonine. In addition, this chromatographic techniques were used as both initial test and confirmatory. The validated chromatographic method was successfully applied to the analysis of cocaine and benzoylecgonine compounds in synthetic biological matrix. Confirmation analyses were made by LC-MS/MS to support reliability of HPLC results. As a result of this study, it can be claimed that HPLC could be a good alternative for the analyses of various biological matrices in forensic studies. Also the matrices and concentrations were determined by HPLC instrument could be used where necessary.

  13. Identification and Determination of Phenolics in Lamiaceae Species by UPLC-DAD-ESI-MS/MS.

    Science.gov (United States)

    Çelik, Saliha Esin; Tufan, Ayse Nur; Bekdeser, Burcu; Özyürek, Mustafa; Güçlü, Kubilay; Apak, Resat

    2017-03-01

    This study reports the phenolic profile screening of aromatic Lamiaceae species such as marjoram (Origanum majorana L.), lavender (Lavandula officinalis) and pennyroyal (Mentha pulegium L.) using a novel and validated ultra performance liquid chromatography method coupled with DAD diode array detector and tandem mass spectrometry (MS/MS) in negative mode of electrospray ionization. Identification and quantification of phenolics in these plant extracts has been realized within 12 min. This method showed good precision (percentage relative standard deviation; RSD% 0.54-2.72 for intra-day, 1.71-4.64 for inter-day), reproducibility (percentage recovery, REC% 92.0-109.0) and linearity (r = 0.9988-0.9999). Limits of detection ranged from 0.02 to 18.2 ng/mL. The extraction of plants was performed using microwave-assisted extraction technique and 60% (v/v) aqueous methanol solvent medium was selected as suitable solvent because of maximum extraction efficiency. Total antioxidant capacity, total phenolic content and free radical scavenging activity of these plant extracts were tested and the results correlated well among each other. According to the Folin assay, phenolic contents of Origanum majorana L., Mentha pulegium L. and Lavandula officinalis were calculated as 119 ± 3.4, 85.1 ± 2.8 and 57.8 ± 2.1 mg GAE/g dry matter, respectively. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  14. MASPECTRAS: a platform for management and analysis of proteomics LC-MS/MS data

    Directory of Open Access Journals (Sweden)

    Rader Robert

    2007-06-01

    Full Text Available Abstract Background The advancements of proteomics technologies have led to a rapid increase in the number, size and rate at which datasets are generated. Managing and extracting valuable information from such datasets requires the use of data management platforms and computational approaches. Results We have developed the MAss SPECTRometry Analysis System (MASPECTRAS, a platform for management and analysis of proteomics LC-MS/MS data. MASPECTRAS is based on the Proteome Experimental Data Repository (PEDRo relational database schema and follows the guidelines of the Proteomics Standards Initiative (PSI. Analysis modules include: 1 import and parsing of the results from the search engines SEQUEST, Mascot, Spectrum Mill, X! Tandem, and OMSSA; 2 peptide validation, 3 clustering of proteins based on Markov Clustering and multiple alignments; and 4 quantification using the Automated Statistical Analysis of Protein Abundance Ratios algorithm (ASAPRatio. The system provides customizable data retrieval and visualization tools, as well as export to PRoteomics IDEntifications public repository (PRIDE. MASPECTRAS is freely available at http://genome.tugraz.at/maspectras Conclusion Given the unique features and the flexibility due to the use of standard software technology, our platform represents significant advance and could be of great interest to the proteomics community.

  15. Enantioselective analysis of etodolac in human plasma by LC-MS/MS: Application to clinical pharmacokinetics.

    Science.gov (United States)

    de Miranda Silva, Carolina; Rocha, Adriana; Tozatto, Eduardo; da Silva, Lucienir Maria; Donadi, Eduardo Antônio; Lanchote, Vera Lucia

    2016-02-20

    Etodolac is a non-steroidal anti-inflammatory drug with preferential inhibition of cyclooxigenase-2 and is widely used in the management of pain in patients with inflammatory arthritis. Etodolac is available as a racemic mixture of (-)-(R)-Etodolac and (+)-(S)-Etodolac; cyclooxigenases inhibition is attributed to (+)-(S)-Etodolac. According to our knowledge, this is the first method for determination of etodolac enantiomers in plasma using LC-MS/MS. Plasma extraction were performed with 25μL of plasma and 1mL of n-hexane:ethyl acetate (95:5); racemic ibuprofen was used as internal standard. Resolution of enantiomers were performed in a Chiralcel(®)OD-H column; deprotonated [M-H](-) and their respective ion products were monitored at transitions of 286>242 for etodolac enantiomers and 205>161 for ibuprofen. The quantitation limit was 3.2ng/mL for both enantiomers in plasma. The method was applied to study the pharmacokinetics of etodolac enantiomers after the administration of a 300 and 400mg dose of racemic drug to a healthy volunteer. Analysis of plasma samples showed higher plasma concentration of (-)-(R)-Etodolacfor both doses (300mg dose: AUC(0-∞)49.80 versus 4.55ugh/mL;400mg dose: AUC(0-∞) 63.90 versus 6.00ugh/mL) with an (R)-(+)/(S)-(-) ratio of approximately 11.

  16. Staphylococcus aureus methicillin resistance detected by HPLC-MS/MS targeted metabolic profiling.

    Science.gov (United States)

    Schelli, Katie; Rutowski, Joshua; Roubidoux, Julia; Zhu, Jiangjiang

    2017-03-15

    Recently, novel bioanalytical methods, such as NMR and mass spectrometry based metabolomics approaches, have started to show promise in providing rapid, sensitive and reproducible detection of Staphylococcus aureus antibiotic resistance. Here we performed a proof-of-concept study focused on the application of HPLC-MS/MS based targeted metabolic profiling for detecting and monitoring the bacterial metabolic profile changes in response to sub-lethal levels of methicillin exposure. One hundred seventy-seven targeted metabolites from over 20 metabolic pathways were specifically screened and one hundred and thirty metabolites from in vitro bacterial tests were confidently detected from both methicillin susceptible and methicillin resistant Staphylococcus aureus (MSSA and MRSA, respectively). The metabolic profiles can be used to distinguish the isogenic pairs of MSSA strains from MRSA strains, without or with sub-lethal levels of methicillin exposure. In addition, better separation between MSSA and MRSA strains can be achieved in the latter case using principal component analysis (PCA). Metabolite data from isogenic pairs of MSSA and MRSA strains were further compared without and with sub-lethal levels of methicillin exposure, with metabolic pathway analyses additionally performed. Both analyses suggested that the metabolic activities of MSSA strains were more susceptible to the perturbation of the sub-lethal levels of methicillin exposure compared to the MRSA strains.

  17. A quick LC-MS-MS method for the determination of flunixin in bovine muscle.

    Science.gov (United States)

    Lugoboni, B; Barbarossa, A; Gazzotti, T; Zironi, E; Farabegoli, F; Pagliuca, G

    2014-03-01

    A simple, fast and cost-effective liquid chromatographic/tandem mass spectrometry (LC-MS-MS) method for the quantitative determination of flunixin (FLU) in bovine muscle was developed and validated. The sample preparation procedure involved an extraction with acetonitrile, followed by evaporation and reconstitution. Chromatographic separation was achieved on a reverse-phase column under programmed conditions. FLU detection was performed with positive electrospray ionization in selected reaction monitoringmode, monitoring one precursor and two products ions. For quantification purposes, FLU-d3 was used as an internal standard. The matrix effect on the analysis of FLU in bovine muscle was evaluated by comparison between calibration curves prepared with standard solution and in blank matrix extracts. The equivalent responses obtained confirmed the absence of signal suppression or/and enhancement. The method was extensively validated according to the parameters requested by European Commission Decision 2002/657/EC in terms of specificity, limit of detection, linearity, trueness, precision, decision limit (CCα) and detection capability (CCβ). FLU stability was also investigated in matrix and in sample extracts at different times and storage conditions.

  18. Stability-Indicating Method and LC-MS-MS Characterization of Forced Degradation Products of Sofosbuvir.

    Science.gov (United States)

    Nebsen, M; Elzanfaly, Eman S

    2016-07-19

    Sofosbuvir is a novel direct acting antiviral agent against hepatitis C virus. In the present work, a rapid, specific and reproducible isocratic reversed phase high performance liquid chromatography (RP-HPLC) method has been developed and validated for the determination of sofosbuvir in the presence of its stressed degradation products. Sobosbuvir was subjected to hydrolysis (acidic, alkaline and neutral), oxidation, photolysis and thermal stress, as per international conference on harmonization (ICH) conditions. The drug showed degradation under oxidative, photolysis, acid and base hydrolysis stress conditions. However, it was stable under thermal and neutral hydrolysis stress conditions. Chromatographic separation of the drug from its degradation products was performed on Inertsil ODS-3 C18 (250 mm × 4.6 mm i.d., 5 µm) column using a green mobile phase of methanol:water 70:30 (v/v). The degradation products were characterized by LC-MS-MS and the fragmentation pathways were proposed. The developed method was validated as per ICH guidelines. No previous method was reported regarding the degradation behavior of sofosbuvir.

  19. Rapid and Reliable Identification of Phospholipids for Untargeted Metabolomics with LC-ESI-QTOF-MS/MS.

    Science.gov (United States)

    Godzien, Joanna; Ciborowski, Michal; Martínez-Alcázar, María Paz; Samczuk, Paulina; Kretowski, Adam; Barbas, Coral

    2015-08-07

    Lipids are important components of biological systems, and their role can be currently investigated by the application of untargeted, holistic approaches such as metabolomics and lipidomics. Acquired data are analyzed to find significant signals responsible for the differentiation between the investigated conditions. Subsequently, identification has to be performed to bring biological meaning to the obtained results. Lipid identification seems to be relatively easy due to the known characteristic fragments; however, the large number of structural isomers and the formation of different adducts makes it challenging and at risk of misidentification. The inspection of data, acquired for plasma samples by a standard metabolic fingerprinting method, revealed multisignal formations for phosphatidylcholines, phosphatidylethanolamines, and sphingomyelins by the formation of ions such as [M + H](+), [M + Na](+), and [M + K](+) in positive ionization mode and [M - H](-), [M + HCOO](-), and [M + Cl](-) in negative mode. Moreover, sodium formate cluster formation was found for [M + H·HCOONa](+) and [H-H·HCOONa](-). The MS/MS spectrum obtained for each of the multi-ions revealed significant differences in the fragmentation, which were confirmed by the analysis of the samples in two independent research centers. After the inspection of an acquired spectra, a list of characteristic and diagnostic fragments was proposed that allowed for easy, quick, and robust lipid identification that provides information about the headgroup, formed adduct, and fatty acyl composition. This ensures successful identification, which is of great importance for the contextualization of data and results validation.

  20. Characterization of the Human Pancreatic Islet Proteome by Two-Dimensional LC/MS/MS

    Energy Technology Data Exchange (ETDEWEB)

    Metz, Thomas O.; Jacobs, Jon M.; Gritsenko, Marina A.; Fontes, Ghislaine; Qian, Weijun; Camp, David G.; Poitout, Vincent J.; Smith, Richard D.

    2006-12-01

    Research to elucidate the pathogenesis of type 1 diabetes mellitus has traditionally focused on the genetic and immunological factors associated with the disease, and, until recently, has not considered the target cell. While there have been reports detailing proteomic analyses of established islet cell lines or isolated rodent islets, the information gained is not always easily extrapolated to humans. Therefore, extensive characterization of the human islet proteome could result in better understanding of islet biology and lead to more effective treatment strategies. We have applied a two-dimensional LC-MS/MS-based analysis to the characterization of the human islet proteome, resulting in the detection of 29,021 unique peptides corresponding to 4,925 proteins. As expected, major islet hormones (insulin, glucagon, somatostatin), beta-cell enriched secretory products (IAPP), ion channels (K-ATP channel), and transcription factors (PDX-1, Nkx 6.1, HNF-1 beta) were detected. In addition, significant proteome coverage of metabolic enzymes and cellular pathways was obtained, including the insulin signaling cascade and the MAP kinase, NF-κβ, and JAK/STAT pathways. This work represents the most extensive characterization of the human islet proteome to date and provides a peptide reference library that may be utilized in future studies of islet biology and type 1 diabetes.

  1. A rapid and sensitive technique for assessing exposure to VX via GC-MS-MS analysis.

    Science.gov (United States)

    McGuire, Jeffrey M; Byers, Christopher E; Hulet, Stanley W; Jakubowski, Edward M; Thomson, Sandra A

    2008-01-01

    A rapid and sensitive method for the determination of the chemical warfare agent VX in plasma taken from Göttingen minipigs has been developed using isotope-dilution gas chromatography-tandem mass spectrometry (GC-MS-MS). Chromatographic separation was achieved on a 5% diphenyl/95% dimethyl polysiloxane capillary column with a total run time of about 11 min. The analyte was detected using ammonia chemical ionization in the multiple reaction monitoring mode, following a simple extraction with 10% 2-propanol in hexane. A good linear relationship was obtained in the quantitative concentration range of 10 ng/mL to 1000 ng/mL (r(2) = 0.9998) with an average slope of 1.275 +/- 0.037 (n = 7), and an absolute detection limit of 0.4 pg on column. The average recovery for VX was 95% in saline in the concentration range of 50-100 ng/mL. The method was successfully applied to the analysis of VX in minipig plasma in a preliminary toxicokinetic study.

  2. Determination of piroxicam from rat articular tissue and plasma based on LC-MS/MS.

    Science.gov (United States)

    Kim, Han Sol; Cho, Ha Ra; Ho, Myoung Jin; Kang, Myung Joo; Choi, Yong Seok

    2016-12-01

    Osteoarthritis (OA) is the most common type of arthritis. To manage OA, in general, oral administration of non-steroidal anti-inflammatory drugs (NSAIDs) is used. Recently, the analgesic and anti-inflammatory efficacy of piroxicam (PX), a long-acting NSAID, by intra-articular (IA) administration in OA was reported, and the possibility that PX is distributed in articular tissues at a certain concentration was raised. Thus, herein, novel LC-MS/MS methods to detect PX in rat articular tissue and plasma are presented. For articular tissue, solvent extraction with acetonitrile for 12 h was employed and a protein precipitation method was used for the preparation of a plasma sample. The developed methods were validated by following the FDA guidelines, and the validated methods were successfully applied to a PK study of IA PX. The present study presents, to our knowledge, the first method of determining a drug in articular tissue. Additionally, the level of PX in articular tissue after IA PX administration was experimentally confirmed for the first time using the present methods. Therefore, the present methods provide a new direction for in vivo evaluation for IA PX formulations and contribute to the development of alternative IA PX formulations with better effects for the treatment of OA.

  3. Exposure assessment approach through mycotoxin/creatinine ratio evaluation in urine by GC-MS/MS.

    Science.gov (United States)

    Rodríguez-Carrasco, Yelko; Moltó, Juan Carlos; Mañes, Jordi; Berrada, Houda

    2014-10-01

    In this pilot survey human urine samples were analyzed for presence of 15 mycotoxins and some of their metabolites using a novel urinary multi-mycotoxin GC-MS/MS method following salting-out liquid-liquid extraction. Fifty-four urine samples from children and adults residents in Valencia were analyzed for presence of urinary mycotoxin and expressed in gram of creatinine. Three out of 15 mycotoxins were detected namely, HT-2 toxin, nivalenol and deoxynivalenol (DON). 37 samples showed quantifiable values of mycotoxins. Co-occurrence of these contaminants was also observed in 20.4% of assayed samples. DON was the most frequently detected mycotoxin (68.5%) with mean levels of 23.3 μg/g creatinine (range: 2.8-69.1 μg/g creatinine). The levels of urinary DON were used to carry out an exposure assessment approach. 8.1% of total subjects were estimated to exceed the DON provisional maximum tolerable daily intake (PMTDI) (1 μg/kg b.w.). Two out of 9 exposed children exceeded the DON PMTDI thus, making them the most exposed based on the urinary results.

  4. HPLC-MS/MS method for quantification of paclitaxel from keratin containing samples.

    Science.gov (United States)

    Turner, Emily A; Stenson, Alexandra C; Yazdani, Saami K

    2017-05-30

    Local drug delivery of paclitaxel is becoming ever more prevalent. As complex drug/excipient combinations are being developed and tested, new high performance liquid chromatography-mass spectrometry (HPLC-MS) techniques capable of quantifying paclitaxel from such formulations are needed. Here a method for quantifying paclitaxel from aqueous, protein and oil containing samples was developed and validated. Keratin, derived from human hair, is the protein component/paclitaxel excipient in the development and validation of said method. The novelty of this method is described by its ability to overcome water solubility issues and address clean-up of residual solvents in clinical grade paclitaxel injection composition. The method evaluates tert-butyl methyl ether and ethanol as extraction solvents with an extraction efficiency of 31.9±2.3% and 86.4±4.5% respectively. Upon evaporation and rehydration, samples were evaluated by HPLC-MS and a method was developed for paclitaxel quantification. The method developed had an inter-day precision of 9.1% relative standard deviation and an intra-day precision of 4.3% relative standard deviation normalized to a docetaxel internal standard. The described method is applicable to any aqueous paclitaxel sample containing protein and/or oils. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Characterization of the human pancreatic islet proteome by two-dimensional LC/MS/MS.

    Science.gov (United States)

    Metz, Thomas O; Jacobs, Jon M; Gritsenko, Marina A; Fontès, Ghislaine; Qian, Wei-Jun; Camp, David G; Poitout, Vincent; Smith, Richard D

    2006-12-01

    The pancreatic beta-cell plays a central role in the maintenance of glucose homeostasis and in the pathogenesis of both type 1 and type 2 diabetes mellitus. Elucidation of the insulin secretory defects observed in diabetes first requires a better understanding of the complex mechanisms regulating insulin secretion, which are only partly understood. While there have been reports detailing proteomic analyses of islet cell lines or isolated rodent islets, the information gained is not always applicable to humans. Therefore, definition of the human islet proteome could contribute to a better understanding of islet biology and lead to more effective treatment strategies. We have applied a two-dimensional LC-MS/MS-based analysis to the characterization of the human islet proteome, resulting in the confident identification of 29,021 different tryptic peptides covering 3365 proteins (> or =2 unique peptide identifications per protein). As expected, the three major islet hormones (insulin, glucagon, and somatostatin) were detected, as well as various beta-cell enriched secretory products, ion channels, and transcription factors. In addition, significant proteome coverage of metabolic enzymes and cellular pathways was observed, including the integrin signaling cascade and the MAP kinase, NF-kappa beta, and JAK/STAT pathways. The resulting peptide reference library provides a resource for future higher throughput and quantitative studies of islet biology.

  6. Development and validation of an HPLC–MS/MS method to determine clopidogrel in human plasma

    Science.gov (United States)

    Liu, Gangyi; Dong, Chunxia; Shen, Weiwei; Lu, Xiaopei; Zhang, Mengqi; Gui, Yuzhou; Zhou, Qinyi; Yu, Chen

    2015-01-01

    A quantitative method for clopidogrel using online-SPE tandem LC–MS/MS was developed and fully validated according to the well-established FDA guidelines. The method achieves adequate sensitivity for pharmacokinetic studies, with lower limit of quantifications (LLOQs) as low as 10 pg/mL. Chromatographic separations were performed on reversed phase columns Kromasil Eternity-2.5-C18-UHPLC for both methods. Positive electrospray ionization in multiple reaction monitoring (MRM) mode was employed for signal detection and a deuterated analogue (clopidogrel-d4) was used as internal standard (IS). Adjustments in sample preparation, including introduction of an online-SPE system proved to be the most effective method to solve the analyte back-conversion in clinical samples. Pooled clinical samples (two levels) were prepared and successfully used as real-sample quality control (QC) in the validation of back-conversion testing under different conditions. The result showed that the real samples were stable in room temperature for 24 h. Linearity, precision, extraction recovery, matrix effect on spiked QC samples and stability tests on both spiked QCs and real sample QCs stored in different conditions met the acceptance criteria. This online-SPE method was successfully applied to a bioequivalence study of 75 mg single dose clopidogrel tablets in 48 healthy male subjects. PMID:26904399

  7. Novel LC- ESI-MS/MS method for desvenlafaxine estimation human plasma: application to pharmacokinetic study.

    Science.gov (United States)

    Kancharla, Pushpa Kumari; Kondru, Venu Gopal Raju; Dannana, Gowri Sankar

    2016-02-01

    A simple, sensitive and specific liquid chromatography tandem mass spectrometry (LC-ESI-MS/MS) method was developed for the quantification of desvenlafaxine in human plasma using desvenlafaxine d6 as an internal standard (IS). Chromatographic separation was performed using a Thermo-BDS hypersil C8 column (50 × 4.6 mm, 3 µm) with an isocratic mobile phase composed of 5 mM ammonium acetate buffer: methanol (20:80, v/v), at a flow rate of 0.80 mL/min. Desvenlafaxine and desvenlafaxine d6 were detected with proton adducts at m/z 264.2/58.1 and 270.2/ 64.1 in multiple reaction monitoring positive mode, respectively. Liquid-liquid extraction was used to extract the drug and the IS. The method was linear over the concentration range 1.001-400.352 ng/mL with a correlation coefficient of ≥0.9994. This method demonstrated intra and inter-day precision within 0.7-5.5 and 1.9-6.8%, and accuracy within 95.3-107.4 and 93.4-99.5%. Desvenlafaxine was found to be stable throughout the freeze-thaw cycles, bench-top and long-term matrix stability studies. The developed and validated method can be successfully applied for the bioequivalence/pharmacokinetic studies of desvenlafaxine in pharmaceutical dosage forms. Copyright © 2015 John Wiley & Sons, Ltd.

  8. Determination of eight pesticides in Lycium barbarum by LC-MS/MS and dietary risk assessment.

    Science.gov (United States)

    Fu, Yan; Yang, Ting; Zhao, Jian; Zhang, Liang; Chen, Ruoxia; Wu, Yinliang

    2017-03-01

    A LC-MS/MS method for determination of eight pesticides (triadimefon, sulfoxaflor, flusilazole, tebuconazole, difenoconazole, amitraz, azoxystrobin, and thiophanate-methyl) in Lycium barbarum was established. The samples were extracted with acetonitrile, and then cleaned up by primary secondary amine. The extracts were diluted with 0.1% formic acid in water. The results showed that at the fortified levels of 0.01-10mg/kg, the average recoveries of these pesticides ranged from 82.1% to 96.2% with the relative standard deviations lower than 7%. The half-lives of eight pesticides were 1.3-5.0days in Lycium barbarum fruits. The pre-harvest interval of all pesticides mentioned above were investigated. Tebuconazole (14days), sulfoxaflor (14days) and flusilazole (28days) have longer pre-harvest interval than the others which have 7days. The dietary risks, assessed as hazard quotients, were far below 100%. The results showed that the eight pesticides applied to Lycium barbarum were comparably safe for the consumer. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Carotenoid composition of jackfruit (Artocarpus heterophyllus), determined by HPLC-PDA-MS/MS.

    Science.gov (United States)

    de Faria, A F; de Rosso, V V; Mercadante, A Z

    2009-06-01

    Carotenoids are pigments responsible for the yellow-reddish color of many foods and are related to important functions and physiological actions, preventing several chronic-degenerative diseases. The objective of this study was to confirm the carotenoid composition of jackfruit by high-performance liquid chromatography connected to photodiode array and mass spectrometry detectors (HPLC-PDA-MS/MS). The main carotenoids were all-trans-lutein (24-44%), all-trans-beta-carotene (24-30%), all-trans-neoxanthin (4-19%), 9-cis-neoxanthin (4-9%) and 9-cis-violaxanthin (4-10%). Either qualitative or quantitative differences, mainly related to the lutein proportion, were found among three batches of jackfruit. Since the fruits from batch A showed significantly lower contents for almost all carotenoids, it also had the lowest total carotenoid content (34.1 microg/100 g) and provitamin A value, whereas the total carotenoid ranged from 129.0 to 150.3 microg/100 g in the other batches. The provitamin A values from batches B and C were 3.3 and 4.3 microg RAE/100 g, respectively. The carotenoid composition of jackfruit was successfully determined, where 14 of the 18 identified carotenoids were reported for first time. Differences among batches may be due to genetic and/or agricultural factors.

  10. Screening and confirmatory method for benzodiazepines and hypnotics in oral fluid by LC-MS/MS.

    Science.gov (United States)

    Kintz, Pascal; Villain, Marion; Concheiro, Marta; Cirimele, Vincent

    2005-06-10

    A procedure is presented for the screening of 17 benzodiazepines and hypnotics in oral fluid after collection with the Intercept(R) device by LC-MS/MS (alprazolam, 7-aminoclonazepam, 7-aminoflunitrazepam, bromazepam, clobazam, diazepam, lorazepam, lormetazepam, midazolam, nordiazepam, oxazepam, temazepam, tetrazepam, triazolam, zaleplon, zopiclone and zolpidem). The method involves extraction of 0.5 mL of oral fluid (previously stored in the Intercept blue buffer) treated with 0.5 mL of phosphate buffer (pH 8.4) in the presence of 5 ng diazepam-d(5) used as internal standard, with 3 mL of diethyl ether/methylene chloride (50/50) and separation using liquid chromatography-tandem mass spectrometry. The limits of quantification for all benzodiazepines and hypnotics range from 0.1 to 0.2 ng/mL. Linearity is observed from the limit of quantification of each compound to 20 ng/mL (r(2)>0.99). Coefficients of variation at 2 ng/mL, measured on 6 points range from 4 to 8% for all drugs, except zopiclone (34%). Extraction recovery, measured at the same concentration was higher than 90%. Ion suppression was evaluated for each compound and was lower than 10% for all drugs except zopiclone (93%). These results were found suitable to screen for 17 benzodiazepines in oral fluid and detect them at very low concentrations, making this method suitable for monitoring subjects under the influence.

  11. Simultaneous determination of sweeteners in beverages by LC-MS/MS.

    Science.gov (United States)

    Sakai, Hiroaki; Yamashita, Azusa; Tamura, Masayoshi; Uyama, Atsuo; Mochizuki, Naoki

    2015-01-01

    A new method was established for the simultaneous determination of 10 sweeteners and a degradation product in beverages by using LC-MS/MS. An ACQUITY UPLC BEH C18 (2.1 × 100 mm, 1.7 μm) was used as the LC column and 0.1% each of aqueous formic acid and formic acid in acetonitrile were used as the mobile phase. A simple and rapid determination of sweeteners was possible by diluting with a solvent, and in the case of some samples containing a large amount of foreign matter, after pre-treatment by diluting with solvent and clean-up of the sample using an Oasis HLB cartridge. All the validation results were satisfactory. As the regulations and standards for sweeteners vary from country to country, a field survey of 58 beverages marketed in Japan was performed using the present method. No issues concerning the labelling or food sanitation law were found in the tested samples.

  12. IPeak: An open source tool to combine results from multiple MS/MS search engines.

    Science.gov (United States)

    Wen, Bo; Du, Chaoqin; Li, Guilin; Ghali, Fawaz; Jones, Andrew R; Käll, Lukas; Xu, Shaohang; Zhou, Ruo; Ren, Zhe; Feng, Qiang; Xu, Xun; Wang, Jun

    2015-09-01

    Liquid chromatography coupled tandem mass spectrometry (LC-MS/MS) is an important technique for detecting peptides in proteomics studies. Here, we present an open source software tool, termed IPeak, a peptide identification pipeline that is designed to combine the Percolator post-processing algorithm and multi-search strategy to enhance the sensitivity of peptide identifications without compromising accuracy. IPeak provides a graphical user interface (GUI) as well as a command-line interface, which is implemented in JAVA and can work on all three major operating system platforms: Windows, Linux/Unix and OS X. IPeak has been designed to work with the mzIdentML standard from the Proteomics Standards Initiative (PSI) as an input and output, and also been fully integrated into the associated mzidLibrary project, providing access to the overall pipeline, as well as modules for calling Percolator on individual search engine result files. The integration thus enables IPeak (and Percolator) to be used in conjunction with any software packages implementing the mzIdentML data standard. IPeak is freely available and can be downloaded under an Apache 2.0 license at https://code.google.com/p/mzidentml-lib/.

  13. HPLC-MS/MS investigation of biochemical markers for the disclosure of erythropoietin abuse in sports

    Science.gov (United States)

    Appolonova, S. A.; Dikunets, M. A.; Rodchenkov, G. M.

    2009-04-01

    The polypeptide hormone erythropoietin (EPO), which is a forbidden doping drug, was determined by high-performance liquid chromatography combined with tandem mass spectrometry (HPLC-MS/MS). The hypothesis about the influence of EPO on the asymmetric dimethylarginine (ADMA)-dimethylargininedime-thylaminohydrolase (DDAH)-NO-synthase system was verified. Changes in this system can serve as indirect biochemical markers of the presence of the forbidden EPO drug in the organism. In the test group, the concentrations of biochemical markers varied from 10 to 40 μg/ml for ADMA and symmetrical DMA (SDMA) and from 0.5 to 10 μg/ml for arginine and citrulline. A single intravenous administration of r-HuEPO (Epocrin, 2000 ME/day) for two volunteers reliably increased ADMA, SDMA, arginine, and citrulline concentrations to 40-270 μg/ml, 40-240μg/ml, 10-60 μg/ml, and 12-140 μg/ml, respectively, with respect to the reference values. The simultaneous increase in arginine, methylarginines, and citrulline contents could be an indirect marker of EPO abuse. The method is recommended for fast screening analysis.

  14. Determination of marbofloxacin in plasma and synovial fluid by ultrafiltration followed by HPLC-MS/MS.

    Science.gov (United States)

    Montesano, Camilla; Curini, Roberta; Sergi, Manuel; Compagnone, Dario; Celani, Gianluca; Varasano, Vincenzo; Petrizzi, Lucio; Amorena, Michele

    2016-05-10

    A rapid LC-MS/MS method for the determination of marbofloxacin in plasma and synovial fluid is presented in this study. The method uses a rapid sample preparation which only requires an ultrafiltration step with centrifugal filter devices. The optimized procedure allows a minimal need of sample (175 μL), particularly useful for synovial fluid samples which amount is rather limited; it is simple, rapid and easily applicable providing anyhow a satisfactory clean up, demonstrated by post-infusion experiments. On the other hand to maximize the speed of the analysis an ultrafast chromatographic separation has been obtained by selecting a column of 20 mm; the reduced run-time is suitable for processing numerous samples on a daily basis. Linearity was assessed in the range 5-2500 ng mL(-1); ofloxacin was used as internal standard. LOD and LOQ were respectively 1 and 5 ng/mL. The method was successfully applied to a set of samples generated during an experimental veterinary study.

  15. UHPLC/ESI-MS/MS Determination of 187 Pesticides in Wine.

    Science.gov (United States)

    Wang, Jian; Cheung, Wendy

    2016-01-01

    This paper presents an ultra HPLC/electrospray ionization-tandem MS method to determine pesticides in wine. We adopted the quick, easy, cheap, effective, rugged, and safe (QuEChERs) method for extraction and used core-shell column to achieve ultra-HPLC to develop and validate a simple and fast method to analyze 187 pesticide residues in red and white wine samples. Pesticide residues were extracted from wine samples using QuEChERS. Ultra HPLC/electrospray ionization-tandem MS quantification was achieved using matrix-matched standard calibration curves with isotopically labeled standards or a chemical analogue as internal standards with an analytical range from 5.0 to 500.0 μg/L. The method performance characteristics that included overall recovery, intermediate precision, and measurement uncertainty were evaluated according to a nested experimental design. Generally, 98.4% (in red wine) and 96.8% (in white wine) of the pesticides had recoveries between 71 and 120%; 98.9% (in red wine) and 99.5% (in white wine) of the pesticides had the intermediate precision ≤20%; and 99.5% (in red wine) and 98.4% (in white wine) of the pesticides had measurement uncertainty ≤50%.

  16. Multi-mycotoxin stable isotope dilution LC-MS/MS method for Fusarium toxins in beer.

    Science.gov (United States)

    Habler, Katharina; Gotthardt, Marina; Schüler, Jan; Rychlik, Michael

    2017-03-01

    A stable isotope dilution LC-MS/MS multi-mycotoxin method was developed for 12 different Fusarium toxins including modified mycotoxins in beer (deoxynivalenol-3-glucoside, deoxynivalenol, 3-acetyldeoxynivalenol, 15-acetyl-deoxynivalenol, HT2-toxin, T2-toxin, enniatin B, B1, A1, A, beauvericin and zearalenone). As sample preparation and purification of beer a combined solid phase extraction for trichothecenes, enniatins, beauvericin and zearalenone was firstly developed. The validation of the new method gave satisfying results: intra-day and inter-day precision and recoveries were 1-5%, 2-8% and 72-117%, respectively. In total, 61 different organic and conventional beer samples from Germany and all over the world were analyzed by using the newly developed multi-mycotoxin method. In summary, deoxynivalenol, deoxynivalenol-3-glucoside, 3-acetyldeoxynivaleneol and enniatin B were quantified in rather low contents in the investigated beer samples. None of the other monitored Fusarium toxins like 15-acetyldeoxynivalenol, HT2- and T2-toxin, zearalenone, enniatin B1, A1, A or beauvericin were detectable.

  17. Development and validation of an HPLC–MS/MS method to determine clopidogrel in human plasma

    Directory of Open Access Journals (Sweden)

    Gangyi Liu

    2016-01-01

    Full Text Available A quantitative method for clopidogrel using online-SPE tandem LC–MS/MS was developed and fully validated according to the well-established FDA guidelines. The method achieves adequate sensitivity for pharmacokinetic studies, with lower limit of quantifications (LLOQs as low as 10 pg/mL. Chromatographic separations were performed on reversed phase columns Kromasil Eternity-2.5-C18-UHPLC for both methods. Positive electrospray ionization in multiple reaction monitoring (MRM mode was employed for signal detection and a deuterated analogue (clopidogrel-d4 was used as internal standard (IS. Adjustments in sample preparation, including introduction of an online-SPE system proved to be the most effective method to solve the analyte back-conversion in clinical samples. Pooled clinical samples (two levels were prepared and successfully used as real-sample quality control (QC in the validation of back-conversion testing under different conditions. The result showed that the real samples were stable in room temperature for 24 h. Linearity, precision, extraction recovery, matrix effect on spiked QC samples and stability tests on both spiked QCs and real sample QCs stored in different conditions met the acceptance criteria. This online-SPE method was successfully applied to a bioequivalence study of 75 mg single dose clopidogrel tablets in 48 healthy male subjects.

  18. Antioxidant capacity and phenolic compounds of Lonicerae macranthoides by HPLC-DAD-QTOF-MS/MS.

    Science.gov (United States)

    Hu, Xin; Chen, Lin; Shi, Shuyun; Cai, Ping; Liang, Xuejuan; Zhang, Shuihan

    2016-05-30

    Lonicerae macranthoides with strong antioxidant activity is commonly used in traditional Chinese medicine and folk tea/beverage. However, detailed information about its antioxidant activity and bioactive compounds is limited. Then at first, we comparatively evaluated total phenolic content (TPC), total flavonoid content (TFC) and antioxidant activities of water extract, petroleum ether, ethyl acetate and n-butanol fractions of L. macranthoides. Ethyl acetate fraction exhibited the highest level of TPC (207.38 mg GAE/g DW), TFC (53.06 mg RE/g DW) and the best DPPH scavenge activity and reducing power. n-Butanol fraction showed the best ABTS(+) and O2(-) scavenging activities. Interestingly, water extract, ethyl acetate and n-butanol fractions showed stronger antioxidant activities than positive control, butylated hydroxytoluene (BHT). After that, thirty-one antioxidant phenolic compounds, including twenty-two phenolic acids and nine flavonoids, were screened by DPPH-HPLC experiment and then identified using HPLC-DAD-QTOF-MS/MS. It is noted that twenty-one compounds (1, 3-4, 6-17, 19, 23, 26, 28-29, and 31), as far as was known, were discovered from L. macranthoide for the first time, and eleven of them (3-4, 10-17, and 23) were reported in Lonicera species for the first time. Results indicated that L. macranthoides could serve as promising source of rich antioxidants in foods, beverages and medicines for health promotion.

  19. Quantitative Determination of Ivermectin in Raw Milk Using Positive ESI LC-MS/MS

    Directory of Open Access Journals (Sweden)

    Meenakshi Dahiya

    2010-01-01

    Full Text Available Ivermectin, a veterinary drug, is commonly used endectocide for animal husbandry. The drug is available in the form of subcutaneous or topical formulations. Its application may cause accumulation of its residues into the animal tissues, which ultimately find their way into the food products, such as milk and meat products. In order to determine the residues of ivermectin in milk, a comparatively simple, sensitive and rapid method was developed and validated using LC-MS/MS. The MRM transitions corresponding to m/z 892.71>569.6, 892.71>551.5 and 892.71>307.3 were used for the purpose of quantification and evaluation of other parameters of the method. The limit of detection of the method was found to be 0.1 μg/kg and the limit of quantitation was calculated as 0.2 μg/kg. The method was found to be linear in the range of 1.0 ng/mL to 100.0 ng/mL with correlation coefficient of 0.9992 for pure calibration curve and 0.9990 for the matrix- matched calibration curve. The recoveries of ivermectin from the spiked samples of raw milk were found between 85 to 105%.

  20. Multifamily determination of pesticide residues in soya-based nutraceutical products by GC/MS-MS.

    Science.gov (United States)

    Páleníková, Agneša; Martínez-Domínguez, Gerardo; Arrebola, Francisco Javier; Romero-González, Roberto; Hrouzková, Svetlana; Frenich, Antonia Garrido

    2015-04-15

    An analytical method based on a modified QuEChERS extraction coupled with gas chromatography-tandem mass spectrometry (GC-MS/MS) was evaluated for the determination of 177 pesticides in soya-based nutraceutical products. The QuEChERS method was optimised and different extraction solvents and clean-up approaches were tested, obtaining the most efficient conditions with a mixture of sorbents (PSA, C18, GBC and Zr-Sep(+)). Recoveries were evaluated at 10, 50 and 100 μg/kg and ranged between 70% and 120%. Precision was expressed as relative standard deviation (RSD), and it was evaluated for more than 160 pesticides as intra and inter-day precision, with values always below 20% and 25%, respectively. Limits of detection (LODs) ranged from 0.1 to 10 μg/kg, whereas limits of quantification (LOQs) from 0.5 to 20 μg/kg. The applicability of the method was proved by analysing soya-based nutraceuticals. Two pesticides were found in these samples, malathion and pyriproxyfen, at 11.1 and 1.5 μg/kg respectively. Copyright © 2014 Elsevier Ltd. All rights reserved.

  1. LC-MS/MS技术在丙溴磷残留检测中的应用%Application of LC-MS/MS in Detection of Profenofos Residues

    Institute of Scientific and Technical Information of China (English)

    贺江

    2012-01-01

    The profenofos residues in samples of rice plant, paddy soil, paddy-filed water, rice hull and brown rice were detected by LC-MS/MS. The results showed that m/z 344.8 and m/z 302.8 can be utilized as qualitative and quantitative ions for profenofos detection; combined pre-treatment method for each sample, the recoveries of profenofos all reached over 80%, the relative standard deviation ranged from 1.05 to 9.56%, and the detection sensitivity reached level of H-g/kg. Therefore, the LC-MS/MS technology can meet the requirements of Guideline on Pesticide Residue Trails in China, which can be applied to detect profenofos residues during rice production.%采用液相色谱-串联质谱(LC-MS/MS)技术对水稻植株、稻田土壤、田水、稻壳以及糙米等样品中的丙溴磷残留进行测定.试验结果表明:丙溴磷的子离子m/z 344.8和m/z 302.8可作为丙溴磷质谱分析的定性、定量确证离子 ;结合各样品前处理方法,丙溴磷的添加回收率均在80%以上,相对标准偏差在1.05%~9.65%之间,检测灵敏度达μg/kg水平.这表明LC-MS/MS技术能达到我国农药残留试验准则的相关规定,可用于水稻生产中丙溴磷的残留的检测.

  2. ESI-MS(2) and Anti-inflammatory Studies of Cyclopropanic Triterpenes. UPLC-ESI-MS and MS(2) Search of Related Metabolites from Donella ubanguiensis.

    Science.gov (United States)

    Sandjo, Louis P; Nascimento, Marcus V P Dos Santos; da Silva, Layzon A L; Munhoz, Antonio C M; Pollo, Luiz A E; Biavatti, Maique W; Ngadjui, Bonaventure T; Opatz, Till; Fröde, Tania S

    2017-01-01

    Triterpenes are one of the largest secondary metabolites groups spread in the plant kingdom with various skeletons. These metabolites have showed various bioactivities including anti-inflammatory activity. The study aims to explore the mass spectrometry fragmentation of donellanic acids A-C (DA A-C), three compounds identified from Donella ubanguiensis; in addition, the fragmentation behaviour of these metabolites will serve as a fingerprint to search and characterise triterpenes congeners in fruits, bark and wood crude extracts of D. ubanguiensis. This work was prompted by the anti-inflammatory activity on leukocyte migration, exudate concentrations and myeloperoxidase activity obtained for DA A-B. The bioactivity was performed on mouse model of pleurisy induced by carrageenan and the parameters were analysed by veterinarian automated cell counter and colorimetric assays. While the tandem mass analyses of DA A-C were carried out by a direct infusion ESI-QTOF-MS/MS, the extracts were studied by UPLC-ESI-QTOF-MS and UPLC-ESI-QTOF-MS/MS. DA A displayed interesting anti-inflammatory activity by inhibiting leukocyte migration, exudate concentrations and myeloperoxidase activity (p  0.05). Moreover, the diagnostic of the MS(2) behaviour of DA A-C in conjunction with the chromatograms and the obtained MS(2) data of the crude extract led to the characterisation of three cyclopropane triterpenes (T1-T3) and six saponins (T4-T9) from the fruits, the bark, and the wood extracts. Donella species deserve more investigation since metabolites related to the anti-inflammatory compound (DA A) could be identified. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  3. Carcinogenic liver fluke Opisthorchis viverrini oxysterols detected by LC-MS/MS survey of soluble fraction parasite extract.

    Science.gov (United States)

    Vale, Nuno; Gouveia, Maria João; Botelho, Mónica; Sripa, Banchob; Suttiprapa, Sutas; Rinaldi, Gabriel; Gomes, Paula; Brindley, Paul J; Correia da Costa, José Manuel

    2013-12-01

    Liquid chromatography in tandem mass spectrometry (LC-MS/MS) has emerged as an informative tool to investigate oxysterols (oxidized derivatives of cholesterol) in helminth parasite associated cancers. Here, we used LC-MS/MS to investigate in soluble extracts of the adult developmental stage of Opisthorchis viverrini from experimentally infected hamsters. Using comparisons with known bile acids and the metabolites of estrogens, the LC-MS data indicated the existence of novel oxysterol derivatives in O. viverrini. Most of these derivatives were ramified at C-17, in similar fashion to bile acids and their conjugated salts. Several were compatible with the presence of an estrogen core, and/or hydroxylation of the steroid aromatic ring A, hydroxylation of both C-2 and C-3 of the steroid ring and further oxidation into an estradiol-2,3-quinone.

  4. LA-ICP-MS of magnetite: Methods and reference materials

    Science.gov (United States)

    Nadoll, P.; Koenig, A.E.

    2011-01-01

    Magnetite (Fe3O4) is a common accessory mineral in many geologic settings. Its variable geochemistry makes it a powerful petrogenetic indicator. Electron microprobe (EMPA) analyses are commonly used to examine major and minor element contents in magnetite. Laser ablation ICP-MS (LA-ICP-MS) is applicable to trace element analyses of magnetite but has not been widely employed to examine compositional variations. We tested the applicability of the NIST SRM 610, the USGS GSE-1G, and the NIST SRM 2782 reference materials (RMs) as external standards and developed a reliable method for LA-ICP-MS analysis of magnetite. LA-ICP-MS analyses were carried out on well characterized magnetite samples with a 193 nm, Excimer, ArF LA system. Although matrix-matched RMs are sometimes important for calibration and normalization of LA-ICP-MS data, we demonstrate that glass RMs can produce accurate results for LA-ICP-MS analyses of magnetite. Cross-comparison between the NIST SRM 610 and USGS GSE-1G indicates good agreement for magnetite minor and trace element data calibrated with either of these RMs. Many elements show a sufficiently good match between the LA-ICP-MS and the EMPA data; for example, Ti and V show a close to linear relationship with correlation coefficients, R2 of 0.79 and 0.85 respectively. ?? 2011 The Royal Society of Chemistry.

  5. Laser desorption postionization for imaging MS of biological material.

    Science.gov (United States)

    Akhmetov, Artem; Moore, Jerry F; Gasper, Gerald L; Koin, Peter J; Hanley, Luke

    2010-02-01

    Vacuum ultraviolet single photon ionization (VUV SPI) is a soft ionization technique that has the potential to address many of the limitations of matrix-assisted laser desorption/ionization (MALDI) for imaging MS. Laser desorption postionization (LDPI) uses VUV SPI for postionization and is experimentally analogous to a MALDI instrument with the addition of a pulsed VUV light source. This review discusses progress in LDPI-MS over the last decade, with an emphasis on imaging MS of bacterial biofilms, analytes whose high salt environment make them particularly resistant to imaging by MALDI-MS. This review first considers fundamental aspects of VUV SPI including ionization mechanisms, cross sections, quantum yields of ionization, dissociation and potential mass limits. The most common sources of pulsed VUV radiation are then described along with a newly constructed LDPI-MS instrument with imaging capabilities. Next, the detection and imaging of small molecules within intact biofilms is demonstrated by LDPI-MS using 7.87 eV (157.6 nm) VUV photons from a molecular fluorine excimer laser, followed by the use of aromatic tags for detection of selected species within the biofilm. The final section considers the future prospects for imaging intact biological samples by LDPI-MS. Copyright 2010 John Wiley & Sons, Ltd.

  6. Screening antioxidants using LC-MS: case study with cocoa.

    Science.gov (United States)

    Calderón, Angela I; Wright, Brian J; Hurst, W Jeffrey; van Breemen, Richard B

    2009-07-08

    Oxidative stress enhances pathological processes contributing to cancer, cardiovascular disease, and neurodegenerative diseases, and dietary antioxidants may counteract these deleterious processes. Because rapid methods to evaluate and compare food products for antioxidant benefits are needed, a new assay based on liquid chromatography-mass spectrometry (LC-MS) was developed for the identification and quantitative analysis of antioxidants in complex natural product samples such as food extracts. This assay is based on the comparison of electrospray LC-MS profiles of sample extracts before and after treatment with reactive oxygen species such as hydrogen peroxide or 2,2-diphenyl-1-picrylhydrazyl radical (DPPH). Using this assay, methanolic extracts of cocoa powder were analyzed, and procyanidins were found to be the most potent antioxidant species. These species were identified using LC-MS, LC-MS/MS, accurate mass measurement, and comparison with reference standards. Furthermore, LC-MS was used to determine the levels of these species in cocoa samples. Catechin and epicatechin were the most abundant antioxidants followed by their dimers and trimers. The most potent antioxidants in cocoa were trimers and dimers of catechin and epicatechin, such as procyanidin B2, followed by catechin and epicatechin. This new LC-MS assay facilitates the rapid identification and then the determination of the relative antioxidant activities of individual antioxidant species in complex natural product samples and food products such as cocoa.

  7. Fach(sprach)lichkeit und Verständlichkeit in Verträgen

    DEFF Research Database (Denmark)

    Larsen, Aase Voldgaard

    2010-01-01

    categories (“lexis” and “syntax”) and in a content related category (“references and intertextuality”). The results provide knowledge about LSP and linguistic features of legal language, more precisely of different types of contracts, i.e. language in use. They can be used for didactic purposes in teaching...... that contracts must be accessible to non-professionals who have less knowledge of genre and linguistic conventions, and this may entail that legal language is changed accordingly. I wish to show what kinds of differences might exist between contracts between professionals and contracts between professionals...... legal language and also by language and law professionals for acquiring knowledge on contracts in relation to non-professionals. The paper will be presented in German. Gunnarsson, Britt-Louise: Lagtexters begriplighet. Lund: LiberFörlag (1982) Fluck, Hans-Rüdiger: Fachsprachen. Einführung und...

  8. Planung von Ausgleichungskursen im Fach Englisch (Planning Assimilation Courses in English)

    Science.gov (United States)

    Kracht, Werner

    1977-01-01

    Students transferring from "terminal" junior high schools or from Realschulen to the Gymnasium (humanities-oriented high school) should take "assimilation courses." These have four phases: (1) evaluation of phonetic knowledge, (2) increasing language skills, (3) introduction to text interpretation, (4) completing an 11th-grade basic course. (Text…

  9. Fachspezifische und fachübergreifende Argumentation am Beispiel von Schöpfung und Evolution

    OpenAIRE

    Weiß, T.

    2016-01-01

    Die Studie ist im deutschsprachigen Raum die erste und bisher einzige, welche am Beispiel Schöpfung und Evolution das Argumentationspotential gymnasialer Oberstufenschülerinnen und Oberstufenschüler (n=48) empirisch erhoben, ausgewertet und fachdidaktische Konsequenzen für die Forschung zur Jugendtheologie abgeleitet hat. Vor den beiden fachwissenschaftlichen Hintergründen - Schöpfung ist eine Erzählung über einen guten Anfang; Evolution ist die Beschreibung zur Entstehung und Entwicklung der...

  10. 2013 BioFach China参展企业超过上届近四成

    Institute of Scientific and Technical Information of China (English)

    尹薇

    2013-01-01

    经历了新版《有机产品认证实施规则》实施后三分之一企业退出有机食品行业的阵痛,在宏观政策指导和市场强劲需求的双重利好下,中国有机食品行业重新迈开坚实有力的脚步大步向前。

  11. BioFach China2010引领有机行业新风潮

    Institute of Scientific and Technical Information of China (English)

    左琼莹

    2010-01-01

    近年来,国内有机消费市场正悄然升温。根据统计,到2015年,年收入超过15万人民币的富裕家庭预计将由2005年的290万户增长到850万户。随着生活质量的提高,消费者将更青睐能够解决食品安全、并带来健康生活的有机产品。“有机”。正成为当下最流行的热门话题之一。

  12. Fach(sprach)lichkeit und Verständlichkeit in Verträgen

    DEFF Research Database (Denmark)

    Larsen, Aase Voldgaard

    2010-01-01

    categories (“lexis” and “syntax”) and in a content related category (“references and intertextuality”). The results provide knowledge about LSP and linguistic features of legal language, more precisely of different types of contracts, i.e. language in use. They can be used for didactic purposes in teaching...

  13. Ein Kompetenzstrukturmodell für den Handlungsaspekt „Ordnen, Strukturieren, Modellieren“ im Fach Chemie

    Directory of Open Access Journals (Sweden)

    Matthias von Arx

    2015-10-01

    Full Text Available In den letzten Jahren sind in vielen Ländern Kompetenzmodelle entwickelt worden, welche als Referenzsysteme für die Festlegung und Überprüfung von Bildungsstandards dienen. In vielen Fällen bleibt es jedoch eine offene Frage, wie spezifische Kompetenzen valide und reliabel erfasst werden können. So existieren beispielsweise keine spezifischen Tests oder theoretischen Modelle, welche die Kompetenz im zentralen naturwissenschaftlichen Kompetenzbereich - Ordnen, Strukturieren, Modellieren (in der Folge nur noch kurz: OSM - des Schweizerischen Kompetenzmodells für die Naturwissenschaften zuverlässig erheben oder beschreiben können. Als Beitrag zur Klärung entwickeln wir hier basierend auf theoretischen Überlegungen ein Modell hierarchischer Komplexität für den Kompetenzbereich OSM (MHC-OSM im Inhaltsbereich Chemie. Das Modell umfasst fünf Kompetenzstufen, deren theoretische Fundierung im Detail beschrieben wird. Eine erste Einordnung des Modells durch einen Vergleich mit der aktuellen Version des Lehrplans 21 sowie mit den seit 2011 festgeschriebenen Grundkompetenzen für die Naturwissenschaften beziehungsweise der Bildungsstandards für den mittleren Schulabschluss in Deutschland zeigt eine gute Passung. Zum Schluss wird aufgezeigt, wie das Modell empirisch validiert werden könnte.

  14. Combinatorial approach of LC-MS/MS and LC-TOF-MS for uncovering in vivo kinetics and biotransformation of ochratoxin A in rat.

    Science.gov (United States)

    Han, Zheng; Zhao, Zhiyong; Shi, Jianxin; Liao, Yucai; Zhao, Zhihui; Zhang, Dabing; Wu, Yongning; De Saeger, Sarah; Wu, Aibo

    2013-04-15

    A combinatorial platform of liquid chromatography-tandem mass spectrometry (LC-MS/MS) and liquid chromatography coupled with time of flight mass spectrometry (LC-TOF-MS) has been developed to investigate the in vivo kinetics and biotransformation of ochratoxin A (OTA) in rats. The stable isotope dilution LC-MS/MS method was first validated by determining the linearity (R(2)≥0.9990), sensitivity (lower limit of quantitation of 0.05 ng mL(-1)), accuracy (83.3-108.3), precision (RSD≤15.6%) and stability (≥75.0%), and was approved for the determination OTA in plasma, heart, liver, spleen, lung, kidney and brain with a run time of 7.0 min. Simultaneously, an LC-TOF-MS method could unambiguously identify the metabolites of OTA in a total run time of 14 min. The subsequent studies on kinetics and distribution after oral administration of 0.2 mg/kg b.w. OTA in rat indicated that OTA could reach a maximum value of 1932.4±124.9 ng mL(-1) within 5h due to its fast absorption, and then was slowly eliminated in plasma with a half-life time (t1/2) of 75.6±29.0 h. Results of tissue accumulation after a daily oral administration of 0.1 mg/kg b.w. OTA during 20 days showed that the highest concentration of OTA was observed in lung (95.9±13.7 ng g(-1)), followed by liver (76.0±9.7 ng g(-1)), heart (62.0±4.2 ng g(-1)) and kidney (55.7±4.7 ng g(-1)). Furthermore, three less toxic metabolites of OTA were clearly identified: Ochratoxin β (OTβ) and ochratoxin B (OTB) methyl ester were found in kidney and spleen, respectively, while phenylalanine was detected in heart and kidney. Thus, a possible metabolic pathway of OTA was proposed. The above achieved results justified that the application of combinatorial LC-MS/MS and LC-TOF-MS methods are valuable tools to uncover the kinetics and metabolism of OTA for the interpretation of toxicological findings in animals and extrapolation of the resulting data as reference to humans.

  15. Sunshine, Sea, and Season of Birth: MS Incidence in Wales.

    Directory of Open Access Journals (Sweden)

    Lloyd D Balbuena

    Full Text Available Maternal sun exposure in gestation and throughout the lifetime is necessary for vitamin D synthesis, and living near the sea is a population level index of seafood consumption. The aim of this study was to estimate the incidence rate of multiple sclerosis (MS in Wales and examine its association with sun exposure, coastal living, and latitude. The study used a database of MS hospital visits and admissions in Wales between 2002 and 2013. For the 1,909 lower layer super output areas (LSOAs in Wales, coastal status, population, longitude/latitude, and average sunshine hours per day were obtained. Age-specific and age-standardised MS incidence were calculated and modelled using Poisson regression. The distribution of births by month was compared between MS cases and the combined England and Wales population. There were 3,557 new MS cases between 2002 and 2013, with an average annual incidence of 8.14 (95% CI: 7.69-8.59 among males and 12.97 (95% CI: 12.44-13.50 among females per 100,000 population. The female-to-male ratio was 1.86:1. For both sexes combined, the average annual incidence rate was 9.10 (95% CI: 8.80-9.40. All figures are age-standardized to the 1976 European standard population. Compared to the combined England and Wales population, more people with MS were born in April, observed-to-expected ratio: 1.21 (95% CI: 1.08-1.36. MS incidence varied directly with latitude and inversely with sunshine hours. Proximity to the coast was associated with lower MS incidence only in easterly areas. This study shows that MS incidence rate in Wales is comparable to the rate in Scotland and is associated with environmental factors that probably represent levels of vitamin D.

  16. Quantitation using GC-TOF-MS: example of bromazepam.

    Science.gov (United States)

    Aebi, B; Sturny-Jungo, R; Bernhard, W; Blanke, R; Hirsch, R

    2002-08-14

    Time-of-flight mass spectrometry (TOF-MS) offers new perspectives for forensic toxicology. Qualitative and quantitative analyses of a mixture of three selected benzodiazepines (diazepam, nordazepam and bromazepam) were used to compare gas chromatography (GC-TOF-MS, quadrupole GC-MS, GC-ECD) and liquid chromatography (HPLC-DAD) data. Method validation parameters like LOD, LOQ, S/N-ratios reflect the capabilities of GC-TOF-MS. Five-point calibrations for bromazepam in human peripheral blood (50, 100, 160, 200, 300 ng/ml) using medazepam as internal standard (1000 ng/ml) were performed. The calibrations using GC-TOF-MS (using the fragments of m/z 236 and 288), GC-ECD (dual system) and HPLC-DAD (at 235 nm) all showed correlation coefficients close or superior to 0.99. Quadrupole GC-MS data was not used in the comparison of extracted samples due to the low sensitivity in the full scan mode. Two analyses of real cases concerning bromazepam are presented. In the first case, the presence or absence of bromazepam could not be established with both HPLC-DAD and GC-ECD due to background signals. The extracted ion chromatograms and spectrum traces after the analysis with the GC-TOF-MS could clearly excluded the presence of bromazepam. The second case illustrates the quantitation of bromazepam, where both HPLC-DAD and GC-ECD were unable to give satisfactory results, again due to interfering background signals. The analyses performed on the GC-TOF-MS-system demonstrated high sensitivity and also high selectivity due to the high quality of mass spectra obtained. The advantages of GC-TOF-MS make it a promising analytical technique for forensic toxicology.

  17. Importance of MS selectivity and chromatographic separation in LC-MS/MS-based methods when investigating pharmaceutical metabolites in water. Dipyrone as a case of study.

    Science.gov (United States)

    Ibáñez, M; Gracia-Lor, E; Sancho, J V; Hernández, F

    2012-08-01

    Pharmaceuticals are emerging contaminants of increasing concern because of their presence in the aquatic environment and potential to reach drinking-water sources. After human and/or veterinary consumption, pharmaceuticals can be excreted in unchanged form, as the parent compound, and/or as free or conjugated metabolites. Determination of most pharmaceuticals and metabolites in the environment is commonly made by liquid chromatography (LC) coupled to mass spectrometry (MS). LC coupled to tandem MS is the technique of choice nowadays in this field. The acquisition of two selected reaction monitoring (SRM) transitions together with the retention time is the most widely accepted criterion for a safe quantification and confirmation assay. However, scarce attention is normally paid to the selectivity of the selected transitions as well as to the chromatographic separation. In this work, the importance of full spectrum acquisition high-resolution MS data using a hybrid quadrupole time-of-flight analyser and/or a suitable chromatographic separation (to reduce the possibility of co-eluting interferences) is highlighted when investigating pharmaceutical metabolites that share common fragment ions. For this purpose, the analytical challenge associated to the determination of metabolites of the widely used analgesic dipyrone (also known as metamizol) in urban wastewater is discussed. Examples are given on the possibilities of reporting false positives of dypirone metabolites by LC-MS/MS under SRM mode due to a wrong assignment of identity of the compounds detected. Copyright © 2012 John Wiley & Sons, Ltd.

  18. Multicenter experiment for quality control of peptide-centric LC-MS/MS analysis - A longitudinal performance assessment with nLC coupled to orbitrap MS analyzers.

    Science.gov (United States)

    Campos, Alex; Díaz, Ramón; Martínez-Bartolomé, Salvador; Sierra, Jose; Gallardo, Oscar; Sabidó, Eduard; López-Lucendo, Maria; Ignacio Casal, J; Pasquarello, Carla; Scherl, Alexander; Chiva, Cristina; Borras, Eva; Odena, Antonia; Elortza, Félix; Azkargorta, Mikel; Ibarrola, Nieves; Canals, Francesc; Albar, Juan P; Oliveira, Eliandre

    2015-09-08

    Proteomic technologies based on mass spectrometry (MS) have greatly evolved in the past years, and nowadays it is possible to routinely identify thousands of peptides from complex biological samples in a single LC-MS/MS experiment. Despite the advancements in proteomic technologies, the scientific community still faces important challenges in terms of depth and reproducibility of proteomics analyses. Here, we present a multicenter study designed to evaluate long-term performance of LC-MS/MS platforms within the Spanish Proteomics Facilities Network (ProteoRed-ISCIII). The study was performed under well-established standard operating procedures, and demonstrated that it is possible to attain qualitative and quantitative reproducibility over time. Our study highlights the importance of deploying quality assessment metrics routinely in individual laboratories and in multi-laboratory studies. The mass spectrometry data have been deposited to the ProteomeXchange Consortium with the data set identifier PXD000205.This article is part of a Special Issue entitled: HUPO 2014.

  19. Determination of Thiamethoxam in Rice by LC-MS/MS%LC-MS/MS测定大米中噻虫嗪农药残留

    Institute of Scientific and Technical Information of China (English)

    聂鲲

    2016-01-01

    The method for determing thiamethoxam in rice has been build utilizing LC-MS/MS technique. The pesticide residues in rice samples were extracted with acetonitrile and by ultrasonic, thiamethoxam were cleaned-up by C18 and PSA as purification sorbent, determined by LC-MS/MS. The lim its of detection were 0.1μg/kg. the average recoveries for The pesticides ranged from 93.5%to 101.2%, with the relative standard deviation(RSD)between 3.12%and 5.84%.%利用LC-MS/MS建立大米中噻虫嗪农药测定的方法。试样中噻虫嗪农药残留在超声波振荡条件下用乙腈提取,经C18和PSA进行分散固相萃取净化,经液相色谱质谱联用仪检测。方法的检出限为0.1μg/kg,回收率为93.5%~101.2%,相对标准偏差为3.12%~5.84%。

  20. GC-MS and GC-MS/MS in PCI mode determination of mescaline in peyote tea and in biological matrices.

    Science.gov (United States)

    Gambelunghe, Cristiana; Marsili, Remo; Aroni, Kyriaki; Bacci, Mauro; Rossi, Riccardo

    2013-01-01

    Peyote, a cactus containing the hallucinogen mescaline, is used to induce altered states of consciousness in religious ceremonies or for recreational purpose. This study reports a case of an underage boy suspected of mescaline abuse. For this purpose, we analyzed a dark green liquid sample found in the bedroom of the boy whose urine and hair samples were collected shortly after the drink was found. A method by gas chromatography-mass spectrometry tandem mass spectrometry (GC-MS/MS) in positive chemical ionization mode was developed and validated in terms of linearity, specificity, accuracy, and sensitivity for mescaline determination at the low concentrations present in hair. GC-MS analysis of the liquid identified mescaline, while urine was negative; GC-MS/MS segmental hair analysis identified mescaline in the proximal segment (root to 2 cm), while the distal segments were negative. Although peyote was uncommonly encountered, its use was confirmed by segmental hair analysis that can provide long-term information about drugs use.

  1. Differentiation of manuka honey from kanuka honey and from jelly bush honey using HS-SPME-GC/MS and UHPLC-PDA-MS/MS.

    Science.gov (United States)

    Beitlich, Nicole; Koelling-Speer, Isabelle; Oelschlaegel, Stefanie; Speer, Karl

    2014-07-01

    In the present study, pollen-identical pure manuka and kanuka honeys and an Australian jelly bush honey were analyzed for the nonvolatiles by UHPLC-PDA-MS/MS and for the volatiles by HS-SPME-GC/MS. A chromatographic profile matchup by means of characteristic marker compounds achieved a clear discrimination between manuka, kanuka, and jelly bush honey. UHPLC-PDA profiles of manuka honey show leptosin, acetyl-2-hydroxy-4-(2-methoxyphenyl)-4-oxobutanate, 3-hydroxy-1-(2-methoxyphenyl)-penta-1,4-dione, kojic acid, 5-methyl-3-furancarboxylic acid, and two unknown compounds as prominent, kanuka honey was characterized by 4-methoxyphenyllactic acid, methyl syringate, p-anisic acid, and lumichrome. 2-Methylbenzofuran, 2'-hydroxyacetophenone, and 2'-methoxyacetophenone were markant volatiles for manuka honey, whereas kanuka honey was characterized by 2,6,6-trimethyl-2-cyclohexene-1,4-dione, phenethyl alcohol, p-anisaldehyde, and an unknown compound in HS-SPME-GC/MS. The jelly bush honey differed from the manuka honey by higher contents of 2-methoxybenzoic acid and an individual unknown substance in the PDA profile and by lower intensities of 2'-methoxyacetophenone, higher concentrations of cis-linalool oxide, and 3,4,5-trimethylphenol in the HS-SPME-GC/MS profile.

  2. A Crease in Gathering 17 of Bodleian MS. Junius 11

    Directory of Open Access Journals (Sweden)

    Alessandra Molinari

    2015-02-01

    Full Text Available This article deals with a crease in gathering 17 of the Old English MS. Junius 11 (Oxford, Bodleian Library, especially with its possible role as evidence that a part of this gathering may have originated as a self-contained booklet before being bound into the MS. After a critical assessment of scholarship on this issue, the article shows that the crease cannot be considered as a piece of evidence for the booklet thesis and that MS. Junius 11 cannot therefore be defined as a composite manuscript.

  3. A concise review of HPLC, LC-MS and LC-MS/MS methods for determination of azithromycin in various biological matrices.

    Science.gov (United States)

    Sharma, Kuldeep; Mullangi, Ramesh

    2013-10-01

    Azithromycin is one of the best selling antibiotics in the world. It belongs to the new macrolide family of azalides. It is derived from erythromycin and it differs from erythromycin in having a 15-membered ring and a methyl substituted nitrogen inserted at the 9a position in the aglycone ring. This structural modification confers favourable microbiological and pharmacokinetic characteristics on azithromycin and greater acid stability compared with erythromycin. It is mainly used to treat respiratory infections, sexually transmitted diseases, cutaneous and soft-tissue infections, etc. This review provides a comprehensive overview of various HPLC, LC-MS and LC-MS/MS methods for quantitation of azithromycin in different biological matrices. In addition, it provides general information on extraction steps, internal standard selection, conditions for chromatographic separation, brief validation data and applicable conclusions for reported methods in a defined pattern.

  4. Stability-indicating HPLC method development and structural elucidation of novel degradation products in posaconazole injection by LC-TOF/MS, LC-MS/MS and NMR.

    Science.gov (United States)

    Yang, Yidi; Zhu, Xi; Zhang, Fei; Li, Wei; Wu, Ying; Ding, Li

    2016-06-05

    Stress testing was carried out under acidic, alkaline, oxidative, thermal and photolytic conditions to evaluate the intrinsic stability of posaconazole injection. A total of four degradation products were detected and the drug was found to be susceptible to oxidative and thermal degradations. Three unknown degradants formed under oxidative stress condition were isolated by preparative HPLC and unambiguously elucidated by LC-TOF/MS, LC-MS/MS, (1)H NMR, (13)C NMR and 2D NMR techniques. Based on the spectrometric and spectroscopic information, these novel degradation products were unequivocally assigned as the N-oxides of posaconazole. Probable mechanisms for the formation of the degradants were proposed. A new and selective HPLC method was developed and validated to separate, detect and quantify all the degradants in posaconazole injection.

  5. Improving metallomics information related to transgenic and non-transgenic soybean seeds using 2D-HPLC-ICP-MS and ESI-MS/MS.

    Science.gov (United States)

    Mataveli, Lidiane Raquel Verola; Fioramonte, Mariana; Gozzo, Fabio César; Arruda, Marco Aurélio Zezzi

    2012-04-01

    This work reports the use of 2D-HPLC-ICP-MS to enlarge metallomics information when considering soybean seeds. Separations using size exclusion chromatography (SEC) allowed the identification of three metal fractions: the first corresponding to molecular weights from 38.1 to 181.1 kDa, the second from 8.2 to 17.2 kDa and the third from 0.4 to 3.8 kDa. In a second dimension, using anion exchange chromatography (AEX), three sub-fractions containing Fe, Mg and Mn, one containing Cu, and three containing Co, Cu, Mg, Mn and Zn were obtained. After these separations, 33 proteins were identified using the ESI-MS/MS technique, and divided into four functional categories: plant growth/cell division, protein destination and storage, metabolism and unclassified proteins. Among the identified proteins, proteins previously related to metals were found.

  6. Nonanthocyanin secondary metabolites of black raspberry (Rubus occidentalis L.) fruits: identification by HPLC-DAD, NMR, HPLC-ESI-MS, and ESI-MS/MS analyses.

    Science.gov (United States)

    Paudel, Liladhar; Wyzgoski, Faith J; Scheerens, Joseph C; Chanon, Ann M; Reese, R Neil; Smiljanic, Danijela; Wesdemiotis, Chrys; Blakeslee, Joshua J; Riedl, Kenneth M; Rinaldi, Peter L

    2013-12-11

    Nonanthocyanin secondary metabolites potentially contributing to the antiproliferative bioactivity of black raspberry ( Rubus occidentalis L.) fruits were extracted in ethyl acetate and isolated by semipreparative and analytical HPLC and analyzed by NMR, HPLC-ESI-MS, and ESI-MS/MS techniques. Here we present complete and partial structures of a variety of the chemical entities such as quercetin 3-glucoside, quercetin 3-rutinoside, myricetin glucoside, dihydrokaempferol glucoside, benzoic acid β-d-glucopyranosyl ester, 3,4-dihydroxybenzoic acid, epicatechin, caffeic acid, p-coumaric acid, p-coumaryl glucoside, p-coumaryl sugar ester, ellagic acid, methyl ellagic acid acetylpentose, methyl ellagic acid valerylpentose, trans-piceid, phloretin glucoside (phloridzin), dihydrosinapic acid, salicylic acid β-d-glucopyranosyl ester, a salicylic acid derivative without attached sugar, p-alkylphenyl glucoside, and a citric acid derivative. To our knowledge, 15 of these compounds were not previously reported in black raspberry fruits.

  7. Analysis of drugs of abuse in hair: evaluation of the immunochemical method VMA-T vs. LC-MS/MS or GC-MS.

    Science.gov (United States)

    Baumgartner, Markus R; Guglielmello, Rosetta; Fanger, Monique; Kraemer, Thomas

    2012-02-10

    Hair analysis is an elaborate and time-consuming multi-step process. The immunometric test VMA-T from Comedical has been evaluated as screening assay for hair analysis. From routine work, authentic samples were selected that were positive for opiates, cocaine, MDMA-type drugs, amphetamines, methadone or THC. These hair samples were investigated by LC-MS or GC-MS and the VMA-T procedure, respectively. Using the cut-off values recommended by the Society of Hair Testing, the VMA-T method discriminates with good sensitivity between negative and positive hair samples and is an expedient screening method for drugs in keratinized matrices such as hair. In order to save time and resources, the residue of the VMA-T extraction solution can be reused for confirmation analysis by LC-MS except for cocaine.

  8. Comparison of Gluten Extraction Protocols Assessed by LC-MS/MS Analysis.

    Science.gov (United States)

    Fallahbaghery, Azadeh; Zou, Wei; Byrne, Keren; Howitt, Crispin A; Colgrave, Michelle L

    2017-04-05

    The efficiency of gluten extraction is of critical importance to the results derived from any analytical method for gluten detection and quantitation, whether it employs reagent-based technology (antibodies) or analytical instrumentation (mass spectrometry). If the target proteins are not efficiently extracted, the end result will be an under-estimation in the gluten content posing a health risk to people affected by conditions such as celiac disease (CD) and nonceliac gluten sensitivity (NCGS). Five different extraction protocols were investigated using LC-MRM-MS for their ability to efficiently and reproducibly extract gluten. The rapid and simple "IPA/DTT" protocol and related "two-step" protocol were enriched for gluten proteins, 55/86% (trypsin/chymotrypsin) and 41/68% of all protein identifications, respectively, with both methods showing high reproducibility (CV gluten class behaving the same.

  9. LC-MS quantification of protein drugs: validating protein LC-MS methods with predigestion immunocapture.

    Science.gov (United States)

    Duggan, Jeffrey; Ren, Bailuo; Mao, Yan; Chen, Lin-Zhi; Philip, Elsy

    2016-09-01

    A refinement of protein LC-MS bioanalysis is to use predigestion immunoaffinity capture to extract the drug from matrix prior to digestion. Because of their increased sensitivity, such hybrid assays have been successfully validated and applied to a number of clinical studies; however, they can also be subject to potential interferences from antidrug antibodies, circulating ligands or other matrix components specific to patient populations and/or dosed subjects. The purpose of this paper is to describe validation experiments that measure immunocapture efficiency, digestion efficiency, matrix effect and selectivity/specificity that can be used during method optimization and validation to test the resistance of the method to these potential interferences. The designs and benefits of these experiments are discussed in this report using an actual assay case study.

  10. LC-MS-MS Method for Determination of Metolazone in Human Plasma

    Directory of Open Access Journals (Sweden)

    Shikha M. N. Roy

    2008-01-01

    Full Text Available A rapid, sensitive and specific method for quantification of metolazone in human plasma using metaxalone as internal standard is described. Sample preparation involved a simple liquid-liquid extraction procedure. The extract was analyzed by high performance liquid chromatography coupled to electrospray tandem mass spectrometry (LC–MS–MS. Chromatography was performed isocratically on a 5 μm C18 analytical column (50 mm × 4.6 mm i.d. with buffer–acetonitrile 20:80 (v/v as mobile phase. The response to metolazone was a linear function of concentration over the range 1.00 to 2000.00 ng mL-1. The lower limit of quantification in plasma was 1.0 ng mL-1. The method was successfully applied in a bioequivalence study of a metolazone formulation after administration as a single oral dose.

  11. Identification of amygdalin and its major metabolites in rat urine by LC-MS/MS.

    Science.gov (United States)

    Ge, B Y; Chen, H X; Han, F M; Chen, Y

    2007-10-01

    Amygdalin and its metabolites in rat urine were identified using liquid chromatography-electrospray ionization (ESI) tandem ion-trap mass spectrometry. The purified rat urine sample was separated using a reversed-phase C18 column with 10 mM sodium phosphate buffer (pH 3.1) containing 30% methanol as the mobile phase, amygdalin and its metabolites were detected by on-line mass detector in selected ion monitoring (SIM) mode. The identification of the metabolites and elucidation of their structure were performed by comparing the changes in molecular masses (DeltaM), retention times and MS(2) spectral patterns of metabolites with those of parent drug. At least seven metabolites and the parent drug were found in rat urine after i.v. injection of 100 mg/kg doses of amygdalin. Among them, six metabolites were reported for the first time.

  12. Metabolites of lorazepam: Relevance of past findings to present day use of LC-MS/MS in analytical toxicology.

    Science.gov (United States)

    Turfus, Sophie C; Braithwaite, Robin A; Cowan, David A; Parkin, Mark C; Smith, Norman W; Kicman, Andrew T

    2011-10-01

    The advent of liquid chromatography-tandem mass spectrometry (LC-MS/MS), with the sensitivity it confers, permits the analysis of both phase I and II drug metabolites that in the past would have been difficult to target using other techniques. These metabolites may have relevance to current analytical toxicology employing LC-MS/MS, and lorazepam was chosen as a model drug for investigation, as only the parent compound has been targeted for screening purposes. Following lorazepam administration (2 mg, p.o.) to 6 volunteers, metabolites were identified in urine by electrospray ionization LC-MS/MS, aided by the use of deuterated analogues generated by microsomal incubation for use as internal chromatographic and mass spectrometric markers. Metabolites present were lorazepam glucuronide, a quinazolinone, a quinazoline carboxylic acid, and two hydroxylorazepam isomers, one of which is novel, having the hydroxyl group located on the fused chlorobenzene ring. The quinazolinone, and particularly the quinazoline carboxylic acid metabolite, provided longer detection windows than lorazepam in urine extracts not subjected to enzymatic hydrolysis, a finding that is highly relevant to toxicology laboratories that omit hydrolysis in order to rapidly reduce the time spent on gas chromatography-mass spectrometry (GC-MS) analysis. With hydrolysis, the longest windows of detection were achieved by monitoring lorazepam, supporting the targeting of the aglycone with free drug for those incorporating hydrolysis in their analytical toxicology procedures.

  13. Comparison of sp-ICP-MS and MDG-ICP-MS for the determination of particle number concentration.

    Science.gov (United States)

    Gschwind, Sabrina; Aja Montes, Maria de Lourdes; Günther, Detlef

    2015-05-01

    In 2011, the European Commission introduced new regulations on how nanomaterials are defined. Since then, researchers have emphasized that more complete characterization of nanoparticles (NPs) includes not just mass and size determinations, but also the determination of the particle number concentrations. In this study, two different sample introduction approaches for the analysis of NP suspensions with inductively coupled plasma mass spectrometry (ICP-MS) were investigated: pneumatic nebulization (sp-ICP-MS) and microdroplet generation (MDG-ICP-MS). These approaches were compared for the determination of particle number concentrations (PNCs) of gold and silver NP suspensions diluted in either ultra-pure water or citrate solution. For accurate sp-ICP-MS analysis, it is crucial to know the transport efficiency of nebulized sample into the plasma. Here, transport efficiencies, measured by the waste collection method, were 11-14 % for Ag suspensions and 9-11 % for Au. In contrast, the droplet transport efficiency of MDG-ICP-MS was 100 %. Analysis by sp-ICP-MS yielded a lower particle number concentration than expected (only 20-40 % of the expected value), whereas MDG-ICP-MS had NP recoveries up to 80 %. This study indicates that NP reference materials are of major importance for particle number determination and detailed results on particle number concentrations for different suspensions with respect to storage time are discussed.

  14. Multi-class determination of anthelmintics in soil and water by LC-MS/MS.

    Science.gov (United States)

    Islam, Marivil D; Haberhauer, Georg; Kist, Alla; Rathor, M Nasir; Gerzabek, Martin; Cannavan, Andrew

    2013-01-01

    The translocation of antiparasitic drugs from animal excrement through soil and water to crops and forages and their recycling to food-producing animals is a potential concern with respect to the contamination of the food chain. To facilitate the investigation of this problem, an LC-MS/MS method for selected anthelmintics in soil and water was developed. The soil sample preparation involved a simple solvent extraction and dispersive clean-up technique. The method was validated at 10, 20 and 40 µg kg(-1) for levamisole, fenbendazole, fenbendazole sulphoxide and fenbendazole sulphone and at 20, 40 and 80 µg kg(-1) for eprinomectin. LOQs were 10 µg kg(-1) for the first four compounds and 20 µg kg(-1) for eprinomectin. The overall mean recoveries ranged from 76.1% to 89% for loamy soils and from 79.9% to 96.9% for sandy soils. Analysis of water samples was performed by extraction/concentration on an Oasis-HLB (Aschaffenburg, Germany) cartridge. Validation was performed at 0.25, 0.5 and 1.0 µg l(-1). The LOQ for all compounds was 0.25 µg l(-1). Method recovery (and RSD) varied between 35.4% (28) for eprinomectin and 125.1% (16) for fenbendazole sulphone. The validated methods were applied to soil and water samples in a study on the behaviour of anthelmintic drugs in a soil-plant-water system (manuscript on "transport investigation of antiparasitic drugs based on a lysimeter experiment" in preparation).

  15. Mass spectrometry (LC-MS/MS) identified proteomic biosignatures of breast cancer in proximal fluid

    Science.gov (United States)

    Whelan, Stephen A.; He, Jianbo; Lu, Ming; Souda, Puneet; Saxton, Romaine E.; Faull, Kym F.; Whitelegge, Julian P.; Chang, Helena R.

    2012-01-01

    Summary We have begun an early phase of biomarker discovery in three clinically important types of breast cancer using a panel of human cell lines: HER2 positive, HER2 negative and hormone receptor positive and triple negative (HER2−, ER−, PR−). We identified and characterized the most abundant secreted, sloughed, or leaked proteins released into serum free media from these breast cancer cell lines using a combination of protein fractionation methods before LC-MS/MS mass spectrometry analysis. A total of 249 proteins were detected in the proximal fluid of 7 breast cancer cell lines. The expression of a selected group of high abundance and/or breast cancer specific potential biomarkers including thromobospondin 1, galectin-3 binding protein, cathepsin D, vimentin, zinc-α2-glycoprotein, CD44, and EGFR from the breast cancer cell lines and in their culture media were further validated by Western blot analysis. Interestingly, mass spectrometry identified a cathepsin D protein single-nucleotide polymorphism (SNP) by alanine to valine replacement from the MCF-7 breast cancer cell line. Comparison of each cell line media proteome displayed unique and consistent biosignatures regardless of the individual group classifications demonstrating the potential for stratification of breast cancer. Based on the cell line media proteome, predictive Tree software was able to categorize each cell line as HER2 positive, HER2 negative and hormone receptor positive and triple negative based on only two proteins, muscle fructose 1,6-bisphosphate aldolase and keratin 19. In addition, the predictive Tree software clearly identified MCF-7 cell line overexpresing the HER2 receptor with the SNP cathepsin D biomarker. PMID:22934887

  16. An improved UPLC-MS/MS platform for quantitative analysis of glycerophosphoinositol in mammalian cells.

    Directory of Open Access Journals (Sweden)

    Laura Grauso

    Full Text Available The glycerophosphoinositols constitute a class of biologically active lipid-derived mediators whose intracellular levels are modulated during physiological and pathological cell processes. Comprehensive assessment of the role of these compounds expands beyond the cellular biology of lipids and includes rapid and unambiguous measurement in cells and tissues. Here we describe a sensitive and simple liquid chromatography-tandem mass spectrometry (LC-MS/MS method for quantitative analysis of the most abundant among these phosphoinositide derivatives in mammalian cells, the glycerophosphoinositol (GroPIns. The method has been developed in mouse Raw 264.7 macrophages with limits of quantitation at 3 ng/ml. Validation on the same cell line showed excellent response in terms of linear dynamic range (from 3 to 3,000 ng/ml, intra-day and inter-day precision (coefficient of variation ≤ 7.10% and accuracy (between 98.1 and 109.0% in the range 10-320 ng/ml. As proof of concept, a simplified analytical platform based on this method and external calibration was also tested on four stimulated and unstimulated cell lines, including Raw 264.7 macrophages, Jurkat T-cells, A375MM melanoma cells and rat basophilic leukemia RBL-2H3 cells. The results indicate a wide variation in GroPIns levels among different cell lines and stimulation conditions, although the measurements were always in line with the literature. No significant matrix effects were observed thus indicating that the here proposed method can be of general use for similar determinations in cells of different origin.

  17. Determination of neomycin and bacitracin in human or rabbit serum by HPLC-MS/MS.

    Science.gov (United States)

    Mascher, Daniel G; Unger, Christian P; Mascher, Hermann J

    2007-01-17

    The method for the simultaneous determination of neomycin and bacitracin in human or rabbit serum was developed by using ion pairing reversed phase chromatography and tandem mass spectrometry (MS/MS) detection with electrospray (ESI) in positive mode. Both substances elute under these conditions at the same time and also kanamycin as internal standard elutes almost at the same time. The sample preparation was simple-only using 0.1 mL serum by protein precipitation with acetonitrile. Neomycin and bacitracin were detected as two-fold charged ions as well as the internal standard. The calibration range of these quite difficult detectable substances was 0.2-50 microg/mL of serum. The method was validated for both human or rabbit serum. The inter batch precision of quality control samples in human serum for neomycin ranged from 4.46% to 8.99% and for bacitracin from 6.85% to 11.17%. The inter batch accuracy for neomycin ranged from 98.7% to 100.7% and for bacitracin from 99.2% to 103.0%. At lower limit of quantitation (LLOQ) level of 0.2 microg/mL inter batch precision in human serum for neomycin was 12.05% and for bacitracin 11.91%, whereas accuracies were 99.9% for neomycin and 102.7% for bacitracin. Bench top stability in human or rabbit serum was given over three freeze thaw cycles and 4h at room temperature. The method can be considered to be specific and recoveries for sample preparation were high.

  18. Quantification of Synthetic Cathinones in Rat Brain Using HILIC-ESI-MS/MS.

    Science.gov (United States)

    Peters, Jacob R; Keasling, Robert; Brown, Stacy D; Pond, Brooks B

    2016-11-01

    The abuse of synthetic cathinones, formerly marketed as "bath salts", has emerged over the last decade. Three common drugs in this class include 3,4-methylenedioxypyrovalerone (MDPV), 4-methylmethcathinone (mephedrone), and 3,4-methylenedioxymethcathinone (methylone). An LC-MS/MS method has been developed and validated for the simultaneous quantification of MDPV, mephedrone, and methylone in brain tissue. Briefly, MDPV, mephedrone, methylone, and their deuterium-labeled analogs were subjected to solid phase extraction (SPE) and separated using an HILIC Silica Column. The HPLC was coupled to a Shimadzu IT-TOF (ion trap-time of flight) system with the electrospray source running in positive mode (+ESI). The method was validated for precision, accuracy, and extraction efficiency. All inter-day and intra-day % RSD (percent relative standard deviation) and % error values were less than 15% and extraction efficiency exceeded 80%. These conditions allowed for limits of detection of 1ng/mL for MDPV, and 5 ng/mL for both mephedrone and methylone. The limits of quantification were determined to be 5ng/mL for MDPV and 10 ng/mL for mephedrone and methylone. The method was utilized to evaluate the pharmacokinetics of these drugs in adult male rats following administration of a drug cocktail including MDPV, mephedrone, and methylone. All three compounds reached peak concentrations in the brain within 15 min. Although methylone and mephedrone were administered at the same dose, the peak concentration (Cmax) of mephedrone in the brain was significantly higher than that for methylone, as was the area under the curve (AUC). In summary, this quick and sensitive method for measuring synthetic cathinones may be used for future pharmacokinetic investigations of these drugs in target tissue. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  19. LC-MS/MS quantification of salvinorin A from biological fluids.

    Science.gov (United States)

    Caspers, Michael J; Williams, Todd D; Lovell, Kimberly M; Lozama, Anthony; Butelman, Eduardo R; Kreek, Mary Jeanne; Johnson, Matthew; Griffiths, Roland; Maclean, Katherine; Prisinzano, Thomas E

    2013-12-21

    A facile method for quantifying the concentration of the powerful and widely available hallucinogen salvinorin A (a selective kappa opioid agonist) from non-human primate cerebrospinal fluid (CSF) and human plasma has been developed using liquid chromatography-tandem mass spectrometry (LC-MS/MS) in positive electrospray ionization (ESI) mode. With CSF solid phase extraction can be avoided completely by simply diluting each sample to 10 % (v/v) acetonitrile, 1 % (v/v) formic acid and injecting under high aqueous conditions for analyte focusing. Extensive plasma sample preparation was investigated including protein precipitation, SPE column selection, and plasma particulate removal. Human plasma samples were centrifuged at 21,000 × gravity for 4 minutes to obtain clear particulate-free plasma, from which 300 μl was spiked with internal standard and loaded onto a C18 SPE column with a 100 mg mL(-1) loading capacity. Guard columns (C18, hand packed 1 mm × 20 mm) were exchanged after backpressure increased above 4600psi, about 250 injections. A shallow acetonitrile/water gradient was used, 29 to 33% CH3CN over 8 minutes to elute salvinorin A. Reduction of chemical noise was achieved using tandem mass spectrometry with multiple reaction monitoring while sensitivity increases were observed using a 50 μL injection volume onto a small bore analytical column (C18, 1 mm ID × 50 mm) thus increasing peak concentration. Limits of quantification were found to be 0.0125 ng mL(-1) (CSF) and 0.05 ng mL(-1) (plasma) with interday precision and accuracy below 1.7 % and 9.42 % (CSF) and 3.47 % and 12.37 % (plasma) respectively. This method was used to determine the concentration of salvinorin A from an in vivo Rhesus monkey study and a trial of healthy human research participants, using behaviorally active doses.

  20. Highly sensitive and specific derivatization strategy to profile and quantitate eicosanoids by UPLC-MS/MS.

    Science.gov (United States)

    Hu, Ting; Tie, Cai; Wang, Zhe; Zhang, Jin-Lan

    2017-01-15

    Eicosanoids are signaling molecules mainly oxidized from arachidonic acid (ARA) and eicosapentaenoic acid (EPA) or docosahexaenoic acid (DHA). They have attracted increasing attention from the scientists attributing to their essential physiological functions. However, their quantification have long been challenged by the low abundance, high structure similarity, poor stability and limited ionization efficiency. In this paper, an ultra-high performance liquid chromatograph coupled with tandem mass spectrometry (UPLC-MS/MS) strategy was developed for the comprehensive profiling of more than 60 eicosanoids based on an efficient derivatization reagent 2,4-bis(diethylamino)-6-hydrazino-1,3,5-triazine (T3) and general multiple reaction monitoring (MRM) parameters. Carboxylic acid of eicosanoid was converted to amide in 30 min at 4 °C with derivatization yield larger than 99%. Limits of quantitation (LOQs) for derivatized eicosanoids varied from 0.05 to 50 pg depending on their structures. The sensitivities of derivatized eicosanoids were enhanced by 10- to 5000-folds compared to free eicosanoids. Stabilities of T3 modified eicosanoids were also highly improved compared to free eicosanoids. This new method can also be used to quantify eicosanoids in bio-samples using isotopic internal standards with high efficiency and reliability within 19 min. 46 and 50 eicosanoids in rat plasma and heart tissue from control and acute myocardial ischemia (AMI) model rats were respectively profiled and quantitated using this new method. And 24 of 46 and 25 of 50 eicosanoids were found to be significantly changed between control and model groups. The changed eicosanoids related to AMI modeling were further statistically analyzed and interpreted based on eicosanoid metabolism pathway.