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F Guyon - One of the best experts on this subject based on the ideXlab platform.

  • Stability of stored Methacholine solutions: study of hydrolysis kinetic by IP-LC.
    Journal of Pharmaceutical and Biomedical Analysis, 2001
    Co-Authors: V. Acar, J.-j. Houri, M.d Le Hoang, D. Pradeau, F Guyon
    Abstract:

    Abstract Methacholine chloride is a powerful cholinergic bronchoconstrictor agent used during bronchial airway hyper-responsiveness diagnosis. Methacholine is susceptible to hydrolysis in aqueous solutions in acetic acid and β-methylcholine. In the present work, kinetics of hydrolysis with different solvents (water and phosphate-buffered saline (PBS) pH 7.4) at different temperatures have been studied using a newly developed high-performance liquid chromatography. At 4°C, kinetic determination of hydrolysis in Methacholine chloride solutions (50 mg/ml) shows no hydrolysis in either aqueous or phosphate-buffered solutions over a 40-day period. At 30°C, concentration of unbuffered Methacholine chloride solutions remained unchanged, but buffered Methacholine chloride solutions have degradation up to 5.5% over a 40-day period. At 40°C, concentration of unbuffered Methacholine chloride has degradation up to 5% and buffered Methacholine chloride solutions have degradation up to 10% over a 40-day period. Methacholine chloride solutions are susceptibly to be used in hospital pharmacy at different concentrations. We have studied pH and osmolality for Methacholine solutions prepared with different diluents potentially used in hospital pharmacies, i.e. deionized water, 0.9% NaCl and PBS pH 7.4. We have demonstrated that Methacholine solutions prepared with deionized water at 50 mg/ml and diluted with PBS pH 7.4 from 5 to 40 mg/ml are isoosmotic and potentially available for inhalation tests to measure non-specific bronchial hyper-responsiveness.

  • Stability of stored Methacholine solutions: study of hydrolysis kinetic by IP-LC.
    Journal of pharmaceutical and biomedical analysis, 2001
    Co-Authors: V. Acar, J.-j. Houri, M.d Le Hoang, D. Pradeau, F Guyon
    Abstract:

    Methacholine chloride is a powerful cholinergic bronchoconstrictor agent used during bronchial airway hyper-responsiveness diagnosis. Methacholine is susceptible to hydrolysis in aqueous solutions in acetic acid and beta-methylcholine. In the present work, kinetics of hydrolysis with different solvents (water and phosphate-buffered saline (PBS) pH 7.4) at different temperatures have been studied using a newly developed high-performance liquid chromatography. At 4 degrees C, kinetic determination of hydrolysis in Methacholine chloride solutions (50 mg/ml) shows no hydrolysis in either aqueous or phosphate-buffered solutions over a 40-day period. At 30 degrees C, concentration of unbuffered Methacholine chloride solutions remained unchanged, but buffered Methacholine chloride solutions have degradation up to 5.5% over a 40-day period. At 40 degrees C, concentration of unbuffered Methacholine chloride has degradation up to 5% and buffered Methacholine chloride solutions have degradation up to 10% over a 40-day period. Methacholine chloride solutions are susceptibly to be used in hospital pharmacy at different concentrations. We have studied pH and osmolality for Methacholine solutions prepared with different diluents potentially used in hospital pharmacies, i.e. deionized water, 0.9% NaCl and PBS pH 7.4. We have demonstrated that Methacholine solutions prepared with deionized water at 50 mg/ml and diluted with PBS pH 7.4 from 5 to 40 mg/ml are isoosmotic and potentially available for inhalation tests to measure non-specific bronchial hyper-responsiveness.

V. Acar - One of the best experts on this subject based on the ideXlab platform.

  • Stability of stored Methacholine solutions: study of hydrolysis kinetic by IP-LC.
    Journal of Pharmaceutical and Biomedical Analysis, 2001
    Co-Authors: V. Acar, J.-j. Houri, M.d Le Hoang, D. Pradeau, F Guyon
    Abstract:

    Abstract Methacholine chloride is a powerful cholinergic bronchoconstrictor agent used during bronchial airway hyper-responsiveness diagnosis. Methacholine is susceptible to hydrolysis in aqueous solutions in acetic acid and β-methylcholine. In the present work, kinetics of hydrolysis with different solvents (water and phosphate-buffered saline (PBS) pH 7.4) at different temperatures have been studied using a newly developed high-performance liquid chromatography. At 4°C, kinetic determination of hydrolysis in Methacholine chloride solutions (50 mg/ml) shows no hydrolysis in either aqueous or phosphate-buffered solutions over a 40-day period. At 30°C, concentration of unbuffered Methacholine chloride solutions remained unchanged, but buffered Methacholine chloride solutions have degradation up to 5.5% over a 40-day period. At 40°C, concentration of unbuffered Methacholine chloride has degradation up to 5% and buffered Methacholine chloride solutions have degradation up to 10% over a 40-day period. Methacholine chloride solutions are susceptibly to be used in hospital pharmacy at different concentrations. We have studied pH and osmolality for Methacholine solutions prepared with different diluents potentially used in hospital pharmacies, i.e. deionized water, 0.9% NaCl and PBS pH 7.4. We have demonstrated that Methacholine solutions prepared with deionized water at 50 mg/ml and diluted with PBS pH 7.4 from 5 to 40 mg/ml are isoosmotic and potentially available for inhalation tests to measure non-specific bronchial hyper-responsiveness.

  • Stability of stored Methacholine solutions: study of hydrolysis kinetic by IP-LC.
    Journal of pharmaceutical and biomedical analysis, 2001
    Co-Authors: V. Acar, J.-j. Houri, M.d Le Hoang, D. Pradeau, F Guyon
    Abstract:

    Methacholine chloride is a powerful cholinergic bronchoconstrictor agent used during bronchial airway hyper-responsiveness diagnosis. Methacholine is susceptible to hydrolysis in aqueous solutions in acetic acid and beta-methylcholine. In the present work, kinetics of hydrolysis with different solvents (water and phosphate-buffered saline (PBS) pH 7.4) at different temperatures have been studied using a newly developed high-performance liquid chromatography. At 4 degrees C, kinetic determination of hydrolysis in Methacholine chloride solutions (50 mg/ml) shows no hydrolysis in either aqueous or phosphate-buffered solutions over a 40-day period. At 30 degrees C, concentration of unbuffered Methacholine chloride solutions remained unchanged, but buffered Methacholine chloride solutions have degradation up to 5.5% over a 40-day period. At 40 degrees C, concentration of unbuffered Methacholine chloride has degradation up to 5% and buffered Methacholine chloride solutions have degradation up to 10% over a 40-day period. Methacholine chloride solutions are susceptibly to be used in hospital pharmacy at different concentrations. We have studied pH and osmolality for Methacholine solutions prepared with different diluents potentially used in hospital pharmacies, i.e. deionized water, 0.9% NaCl and PBS pH 7.4. We have demonstrated that Methacholine solutions prepared with deionized water at 50 mg/ml and diluted with PBS pH 7.4 from 5 to 40 mg/ml are isoosmotic and potentially available for inhalation tests to measure non-specific bronchial hyper-responsiveness.

R.j. Harbeck - One of the best experts on this subject based on the ideXlab platform.

  • Effect of pH on the stability of Methacholine chloride in solution
    Respiratory medicine, 1998
    Co-Authors: B.l. Watson, R.a. Cormier, R.j. Harbeck
    Abstract:

    Abstract Methacholine chloride bronchoprovocation challenges are performed for the diagnosis and investigation of hyperreactive airways. Over the last 20 yrs various formulations and pH values for the preparation of solutions of Methacholine have been described. To determine the stability of Methacholine chloride solutions prepared in a variety of buffers with differing pH values and under varying storage temperatures, we measured Methacholine concentrations at intervals from 1 to 5 weeks. It was found that Methacholine chloride solutions rapidly decompose if the pH is greater than 6 and that decomposition is more rapid as the pH is raised; solutions at pH 9, i.e. bicarbonate buffer, and stored at 27°C have degradation up to 36% after only one week. Solutions of the same pH but prepared in different buffers can have both varied rates of deterioration and different absolute amounts of Methacholine hydrolysed, e.g. solutions prepared in pH 9 borate buffer and stored at 27°C have up to 60% degradation after 1 week. Solutions prepared in saline are stable probably because Methacholine solutions are weakly acidic. The results emphasise the importance of preparing Methacholine chloride in the proper buffers for use in the accurate assessment of airway responsiveness.

D. Pradeau - One of the best experts on this subject based on the ideXlab platform.

  • Stability of stored Methacholine solutions: study of hydrolysis kinetic by IP-LC.
    Journal of Pharmaceutical and Biomedical Analysis, 2001
    Co-Authors: V. Acar, J.-j. Houri, M.d Le Hoang, D. Pradeau, F Guyon
    Abstract:

    Abstract Methacholine chloride is a powerful cholinergic bronchoconstrictor agent used during bronchial airway hyper-responsiveness diagnosis. Methacholine is susceptible to hydrolysis in aqueous solutions in acetic acid and β-methylcholine. In the present work, kinetics of hydrolysis with different solvents (water and phosphate-buffered saline (PBS) pH 7.4) at different temperatures have been studied using a newly developed high-performance liquid chromatography. At 4°C, kinetic determination of hydrolysis in Methacholine chloride solutions (50 mg/ml) shows no hydrolysis in either aqueous or phosphate-buffered solutions over a 40-day period. At 30°C, concentration of unbuffered Methacholine chloride solutions remained unchanged, but buffered Methacholine chloride solutions have degradation up to 5.5% over a 40-day period. At 40°C, concentration of unbuffered Methacholine chloride has degradation up to 5% and buffered Methacholine chloride solutions have degradation up to 10% over a 40-day period. Methacholine chloride solutions are susceptibly to be used in hospital pharmacy at different concentrations. We have studied pH and osmolality for Methacholine solutions prepared with different diluents potentially used in hospital pharmacies, i.e. deionized water, 0.9% NaCl and PBS pH 7.4. We have demonstrated that Methacholine solutions prepared with deionized water at 50 mg/ml and diluted with PBS pH 7.4 from 5 to 40 mg/ml are isoosmotic and potentially available for inhalation tests to measure non-specific bronchial hyper-responsiveness.

  • Stability of stored Methacholine solutions: study of hydrolysis kinetic by IP-LC.
    Journal of pharmaceutical and biomedical analysis, 2001
    Co-Authors: V. Acar, J.-j. Houri, M.d Le Hoang, D. Pradeau, F Guyon
    Abstract:

    Methacholine chloride is a powerful cholinergic bronchoconstrictor agent used during bronchial airway hyper-responsiveness diagnosis. Methacholine is susceptible to hydrolysis in aqueous solutions in acetic acid and beta-methylcholine. In the present work, kinetics of hydrolysis with different solvents (water and phosphate-buffered saline (PBS) pH 7.4) at different temperatures have been studied using a newly developed high-performance liquid chromatography. At 4 degrees C, kinetic determination of hydrolysis in Methacholine chloride solutions (50 mg/ml) shows no hydrolysis in either aqueous or phosphate-buffered solutions over a 40-day period. At 30 degrees C, concentration of unbuffered Methacholine chloride solutions remained unchanged, but buffered Methacholine chloride solutions have degradation up to 5.5% over a 40-day period. At 40 degrees C, concentration of unbuffered Methacholine chloride has degradation up to 5% and buffered Methacholine chloride solutions have degradation up to 10% over a 40-day period. Methacholine chloride solutions are susceptibly to be used in hospital pharmacy at different concentrations. We have studied pH and osmolality for Methacholine solutions prepared with different diluents potentially used in hospital pharmacies, i.e. deionized water, 0.9% NaCl and PBS pH 7.4. We have demonstrated that Methacholine solutions prepared with deionized water at 50 mg/ml and diluted with PBS pH 7.4 from 5 to 40 mg/ml are isoosmotic and potentially available for inhalation tests to measure non-specific bronchial hyper-responsiveness.

M.d Le Hoang - One of the best experts on this subject based on the ideXlab platform.

  • Stability of stored Methacholine solutions: study of hydrolysis kinetic by IP-LC.
    Journal of Pharmaceutical and Biomedical Analysis, 2001
    Co-Authors: V. Acar, J.-j. Houri, M.d Le Hoang, D. Pradeau, F Guyon
    Abstract:

    Abstract Methacholine chloride is a powerful cholinergic bronchoconstrictor agent used during bronchial airway hyper-responsiveness diagnosis. Methacholine is susceptible to hydrolysis in aqueous solutions in acetic acid and β-methylcholine. In the present work, kinetics of hydrolysis with different solvents (water and phosphate-buffered saline (PBS) pH 7.4) at different temperatures have been studied using a newly developed high-performance liquid chromatography. At 4°C, kinetic determination of hydrolysis in Methacholine chloride solutions (50 mg/ml) shows no hydrolysis in either aqueous or phosphate-buffered solutions over a 40-day period. At 30°C, concentration of unbuffered Methacholine chloride solutions remained unchanged, but buffered Methacholine chloride solutions have degradation up to 5.5% over a 40-day period. At 40°C, concentration of unbuffered Methacholine chloride has degradation up to 5% and buffered Methacholine chloride solutions have degradation up to 10% over a 40-day period. Methacholine chloride solutions are susceptibly to be used in hospital pharmacy at different concentrations. We have studied pH and osmolality for Methacholine solutions prepared with different diluents potentially used in hospital pharmacies, i.e. deionized water, 0.9% NaCl and PBS pH 7.4. We have demonstrated that Methacholine solutions prepared with deionized water at 50 mg/ml and diluted with PBS pH 7.4 from 5 to 40 mg/ml are isoosmotic and potentially available for inhalation tests to measure non-specific bronchial hyper-responsiveness.

  • Stability of stored Methacholine solutions: study of hydrolysis kinetic by IP-LC.
    Journal of pharmaceutical and biomedical analysis, 2001
    Co-Authors: V. Acar, J.-j. Houri, M.d Le Hoang, D. Pradeau, F Guyon
    Abstract:

    Methacholine chloride is a powerful cholinergic bronchoconstrictor agent used during bronchial airway hyper-responsiveness diagnosis. Methacholine is susceptible to hydrolysis in aqueous solutions in acetic acid and beta-methylcholine. In the present work, kinetics of hydrolysis with different solvents (water and phosphate-buffered saline (PBS) pH 7.4) at different temperatures have been studied using a newly developed high-performance liquid chromatography. At 4 degrees C, kinetic determination of hydrolysis in Methacholine chloride solutions (50 mg/ml) shows no hydrolysis in either aqueous or phosphate-buffered solutions over a 40-day period. At 30 degrees C, concentration of unbuffered Methacholine chloride solutions remained unchanged, but buffered Methacholine chloride solutions have degradation up to 5.5% over a 40-day period. At 40 degrees C, concentration of unbuffered Methacholine chloride has degradation up to 5% and buffered Methacholine chloride solutions have degradation up to 10% over a 40-day period. Methacholine chloride solutions are susceptibly to be used in hospital pharmacy at different concentrations. We have studied pH and osmolality for Methacholine solutions prepared with different diluents potentially used in hospital pharmacies, i.e. deionized water, 0.9% NaCl and PBS pH 7.4. We have demonstrated that Methacholine solutions prepared with deionized water at 50 mg/ml and diluted with PBS pH 7.4 from 5 to 40 mg/ml are isoosmotic and potentially available for inhalation tests to measure non-specific bronchial hyper-responsiveness.