SIMULTANEOUS QUANTITATIVE DETERMINATION OF CALCIUM GLUCONATE AND ITS IMPURITIES (CI^- SO₄^2-) BY ION CHROMATOGRAPHY

Ion chromatographic separation and determination of calcium gluconate and its impurities (Cl^-, SO₄^2-) were studied. Waters ILC-1 Ion/Liquid chromatograph, 50 × 4.6 mm ID stainless steel IC-PAK A column were used, pH 6.6 1 × 10^-3 mol/L phthalic acid as mobile phase at a flow rate of 1.2 ml/min, 430 conductivity detector with 5μS FS. The results obtained by external standard method, external standard single-point calibration method and Chinese Pharmacopoeia method were in good agreement. The average recoveries of the two proposed methods were 100.8% (C1^-) and 100.2% (SO₄^2-), the correlation coefficients were 0.9951 (C1^-) and 0.9961 (SO₄^2-) (n=8) respectively. This method is simple, relatively fast and can be used for simultaneous quantitative determination of this drug and its impurities.