在pH8.93的三羟甲基氨基甲烷-盐酸介质中,一定量的阿莫西林与1.0×10-5mol·L-1亚甲基蓝溶液1.5 mL在总体积10 mL中反应生成离子缔合物,产生共振瑞利散射光谱,在其最大共振光散射峰369 nm波长处测定共振瑞利散射的强度IRRS。阿莫西林浓度在2.0×10-7~1.0×10-6mol·L-1范围内,与样品及空白溶液IRRS值之差ΔIRRS呈线性关系,方法的检出限(3s/k)为7.8×10-8mol·L-1。方法用于药物中阿莫西林的测定,测得结果与药典法测得结果相符。

In a Tris-HCl buffer medium of pH 8.93, an appropriate amount of amoxicillin sample solution was reacted with 1.5 mL of 1.0×10-5mol·L-1 methylene blue solution in a total volume of 10 mL, to form an ion association complex, of which the intensity of resonance Rayleigh scattering (IRRS) was measured at the wavelength of 369 nm. Values of ΔIRRS (difference between values of IRRS of sample and blank) were found to keep linear relationship with values of concentration of amoxicillin in the range of 2.0×10-7-1.0×10-6mol·L-1, with detection limit (3s/k) of 7.8×10-8mol·L-1. The proposed method was applied to the determination of amoxicillin in samples of capsules and injections, results obtained by this method were found to check quite well with the results found by the method of pharmacopeia.