【摘要】 在稀磷酸介质中,利用抗坏血酸对亚硝酸根催化溴酸钾氧化孔雀石绿的阻抑作用,通过测量620nm下吸光度的改变,建立测定抗坏血酸的阻抑动力学光度分析的新方法.方法的线性范围为0.2～1.40μg/mL,检出限为2.5×10-7g/mL.对10.0μg/25mL抗坏血酸进行10次平行测定的相对标准偏差为3.2%.用于维生素片中微量抗坏血酸的测定,结果满意.更多还原

【Abstract】 A new inhibition kinetic spectrophotometric method for the determination of micro ascorbic acid is studied. The method is based on the inhibition ofascorbic acid on the nitrite catalyzed oxidation of malachite green by potassium bromate in phosphoric acid medium. The absorbance is measured at 620 nm. The linear range of determination is 0.20～1.40 μg/mL. The detection limit is 2.5×10-7 g/mL. The relative standard deviation was 3.2%(n=10,10.0 μg/25mL, ascorbic acid). The method is applied to the determination of ascorbic acid in vitamin C tablet with satisfactory results.更多还原