在pH 7.56的Tris-盐酸缓冲溶液中,一定量的甲砜霉素与1.0×10-3mol·L-1溴甲酚绿溶液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波长340 nm处测定共振瑞利散射的强度IRRS。甲砜霉素的质量浓度在0.02~0.36 mg·L-1范围内与扣除空白值的相应共振瑞利散射强度ΔIRRS呈线性关系,方法的检出限(3s/k)为0.065 mg·L-1。方法用于测定两种甲砜霉素药物中甲砜霉素的含量,并以此试样为基体,用标准加入法做回收率和精密度试验,测得其平均回收率在98.9%~102%之间,相对标准偏差(n=6)在1.4%~1.7%之间。

In a Tris-HCl buffer medium of pH 7.56, a definite amount of thiamphenicol was reacted with 1.5 mL of 1.0×10-3mol·L-1 bromocresol green 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 RRS peak wavelength of 340 nm. Values of ΔIRRS (difference between values of IRRS of testing solution and blank) was found to keep linear relationship with values of mass concentration of thiamphenicol in the range of 0.02-0.36 mg·L-1, with value of detection limit (3s/k) of 0.065 mg·L-1. The proposed method was applied to the determination of triamphenicol in 2 medicines, and tests for recovery and precision were made by standard addition method using these samples as matrixes. Values of average recovery and RSD＇s (n=6) found were in ranges of 98.9%-102% and 1.4%-1.7% respectively.