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Sample records for chloramine-b

  1. Kinetic determination of iodide by the oxidation reaction of benzidine with chloramine B

    International Nuclear Information System (INIS)

    Iodide catalyzed oxidation of benzidine with Chloramine B is studied for its possible application to kinetic determination of iodides. Based on the results of kinetic studies performed, optimal conditions for the catalytic reaction are revealed and a kinetic method for iodide determination is developed. The determination limit of iodide is 2x10-4 μg/ml. It was demonstrated that the proposed method can be used for the determination of iodides in water, soil, and kelp

  2. Oxidation of Tetracaine Hydrochloride by Chloramine-B in Acid Medium: Kinetic Modeling

    Directory of Open Access Journals (Sweden)

    Jayachamarajapura Pranesh Shubha

    2014-01-01

    Full Text Available Tetracaine hydrochloride (TCH is one of the potent local anaesthetics. A kinetic study of oxidation of tetracaine hydrochloride by sodium N-chlorobenzenesulfonamide (chloramine-B or CAB has been carried in HClO4 medium at 303 K. The rate shows first-order dependence on [CAB]o, shows fractional–order dependence on [substrate]o, and is self-governing on acid concentration. Decrease of dielectric constant of the medium, by adding methanol, increased the rate. Variation of ionic strength and addition of benzenesulfonamide or NaCl have no significant effect on the rate. The reaction was studied at different temperatures and the activation parameters have been evaluated. The stoichiometry of the reaction was found to be 1 : 5 and the oxidation products were identified by spectral analysis. The conjugate free acid C6H5SO2NHCl of CAB is postulated as the reactive oxidizing species. The observed results have been explained by plausible mechanism and the related rate law has been deduced.

  3. Kinetics and Mechanistic Chemistry of Oxidation of Butacaine Sulfate by Chloramine-B in Acid Medium

    Energy Technology Data Exchange (ETDEWEB)

    Shubha, Jayachamarajapura Pranesh; Kotabagi, Vinutha [Bosco Institute of Technology, Bangalore (India); Puttaswamy [Bangalore Univ., Bangalore (India)

    2012-11-15

    Butacaine sulfate is an ester of p-aminobenzoic acid which has been widely used as a local anaesthetic and it is a long standing agent particularly for spinal anaesthesia. For this reason, a kinetic study of oxidation of butacaine sulfate by sodium N-chlorobenzenesulfonamide (chloramine-B or CAB) has been carried out in HClO{sub 4} medium at 303 K in order to explore this redox system mechanistic chemistry. The rate shows a first-order dependence on both [CAB]{sub o}, and [substrate]{sub o}, and a fractional-order dependence on acid concentration. Decrease of dielectric constant of the medium, by adding methanol, increases the rate of the reaction. Variation of ionic strength and addition of benzenesulfonamide or NaCl have no significant effect on the rate. The reaction was studied at different temperatures and the activation parameters have been evaluated. The stoichiometry of the reaction has been found to be 1:2 and the oxidation products have been identified by spectral analysis. The observed results have been explained by plausible mechanism and the related rate law has been deduced.

  4. KINETICS OF OXIDATION OF SALBUTAMOL BY CHLORAMINE-B IN NaOH MEDIUM: A MECHANISTIC APPROACH

    Directory of Open Access Journals (Sweden)

    Iyengar Pushpa

    2012-04-01

    Full Text Available The kinetics of oxidation of salbutamol (SBL by N-chlorobenzenesulphonamide (CAB in NaOH medium has been investigated at 303K. The reaction rate shows a first order dependence on [CAB]0 , fractional order with respect to [SBL]0 and a negative fractional order with respect to [OH-] . The addition of the reduction product, benzenesulphonamide , retards the reaction rate. The effect of dielectric constant of the medium by varying [MeOH] shows an inverse effect. The addition of chloride ions and variation of ionic strength of the medium have no significant effect on the rate of the reaction. The reaction fails to initiate polymerization of acrylamide. The oxidation products were identified. The Michaelis – Menten type of kinetics has been proposed. The reaction was studied at different temperatures and the values of thermodynamic parameters were computed. A mechanism consistent with the observed kinetics is proposed.

  5. Powerful colloidal silver nanoparticles for the prevention of gastrointestinal bacterial infections

    Science.gov (United States)

    Le, Anh-Tuan; Tam Le, Thi; Quy Nguyen, Van; Hoang Tran, Huy; Dang, Duc Anh; Tran, Quang Huy; Vu, Dinh Lam

    2012-12-01

    In this work we have demonstrated a powerful disinfectant ability of colloidal silver nanoparticles (NPs) for the prevention of gastrointestinal bacterial infections. The silver NPs colloid was synthesized by a UV-enhanced chemical precipitation. Two gastrointestinal bacterial strains of Escherichia coli (ATCC 43888-O157:k-:H7) and Vibrio cholerae (O1) were used to verify the antibacterial activity of the as-prepared silver NPs colloid by means of surface disinfection assay in agar plates and turbidity assay in liquid media. Transmission electron microscopy was also employed to analyze the ultrastructural changes of bacterial cells caused by silver NPs. Noticeably, our silver NPs colloid displayed a highly effective bactericidal effect against two tested gastrointestinal bacterial strains at a silver concentration as low as ∼3 mg l‑1. More importantly, the silver NPs colloid showed an enhancement of antibacterial activity and long-lasting disinfectant effect as compared to conventional chloramin B (5%) disinfection agent. These advantages of the as-prepared colloidal silver NPs make them very promising for environmental treatments contaminated with gastrointestinal bacteria and other infectious pathogens. Moreover, the powerful disinfectant activity of silver-containing materials can also help in controlling and preventing further outbreak of diseases.

  6. Powerful colloidal silver nanoparticles for the prevention of gastrointestinal bacterial infections

    International Nuclear Information System (INIS)

    In this work we have demonstrated a powerful disinfectant ability of colloidal silver nanoparticles (NPs) for the prevention of gastrointestinal bacterial infections. The silver NPs colloid was synthesized by a UV-enhanced chemical precipitation. Two gastrointestinal bacterial strains of Escherichia coli (ATCC 43888-O157:k-:H7) and Vibrio cholerae (O1) were used to verify the antibacterial activity of the as-prepared silver NPs colloid by means of surface disinfection assay in agar plates and turbidity assay in liquid media. Transmission electron microscopy was also employed to analyze the ultrastructural changes of bacterial cells caused by silver NPs. Noticeably, our silver NPs colloid displayed a highly effective bactericidal effect against two tested gastrointestinal bacterial strains at a silver concentration as low as ∼3 mg l−1. More importantly, the silver NPs colloid showed an enhancement of antibacterial activity and long-lasting disinfectant effect as compared to conventional chloramin B (5%) disinfection agent. These advantages of the as-prepared colloidal silver NPs make them very promising for environmental treatments contaminated with gastrointestinal bacteria and other infectious pathogens. Moreover, the powerful disinfectant activity of silver-containing materials can also help in controlling and preventing further outbreak of diseases. (paper)

  7. In vitro selection of beans (Phaseolus vulgaris) from Costa Rica for resistance to fungal pathogen Thanatephorus cucumeris (Rhizoctonia solani)

    International Nuclear Information System (INIS)

    The research has been realized in the Laboratory of Plant Pathology and Laboratory of Plant Tissue Cultures of the Department of Botany in the Palacky University, Olomouc during the period 3 September - 21 December 2007. In vitro cultivation of beans seeds.The culture medium AC agar (Sigma) was used for Thanatephorus cucumeris. The next three isolates from Costa Rica were tested: 007-3242, 007-3241, 007-3077. For each pathogen isolate three different doses were evaluated: 1%, 5% and 10%. The medium was added before it was autoclaved. Two bean varieties (Brunca /black color/ and Bribri /red color/) were used during this procedure. In order to cultivate the bean seeds the Murashige/Skoog (MS) (Duchefa) culture medium was used. The bean seeds were sterilized with Chloramine B (2.5%) for 30 min, washing them three times with distilled sterile water and then leaving the seeds into distilled sterile water for 24 hours. The seed coat was eliminated, and then the embryos were extirpated, and placed in Petri dishes for two days, after two days of incubation the roots were cut and transferred to Erlenmeyer flasks. They were cultivated in the growth chamber at a temperature of 24 + 2 deg. C and a photoperiod of 16 hours /8 day/night. The evaluations were made during the 30, 40 and 50 days of incubation. The spray method was used in order to inoculate Thanatephorus cucumeris from the in vitro bean seedlings. After three weeks of incubation the seedlings were inoculated (by using a glass sprayer) with T. cucumeris (treatments of 1%, 5%, 10%, 2 ml per/ Erlenmeyer flask) in aseptic conditions. The evaluation was made 12 days after the inoculation. The results obtained so far are preliminary, the collected data needs to be analyzed statistically, so it can be published this year. (author)