Application of the WATR Technique for Water Suppression in 1H NMR Spectroscopy in Determination of The Kinetics of Hydrolysis of Neostigmine Bromide in Aqueous Solution

  title={Application of the WATR Technique for Water Suppression in 1H NMR Spectroscopy in Determination of The Kinetics of Hydrolysis of Neostigmine Bromide in Aqueous Solution},
  author={Abu J. Ferdous and Roger D. Waigh},
  journal={Journal of Pharmacy and Pharmacology},
Abstract— Both ammonium chloride and guanidinium chloride were used to secure water suppression in 1H NMR spectra using the ‘Water Attenuation by T2 Relaxation’ (WATR) technique. The effect of phosphate buffer in the suppression was investigated over a range of pH values at 80 MHz. The spin‐spin relaxation time of water protons at 80 MHz was found to reach a minimum at pH 7·3 in the presence of 0·1 m phosphate buffer and 1 m guanidinium chloride; these conditions were therefore chosen for… 
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Quantitative NMR spectroscopy--applications in drug analysis.

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The WATR method for water suppression in 1H NMR spectroscopy has been evaluated at 80 MHz, using both ammonium and guanidinium chloride, with and without the addition of buffer salts. The pH of