在pH 9.66的Tris-盐酸缓冲溶液中,氯霉素与酸性铬蓝K反应形成具有正吸收和负吸收的离子缔合物,最大正吸收波长为498 nm,最大负吸收波长为594 nm,线性范围分别在3.2 mg·L-1(正吸收)、3.9 mg·L-1(负吸收)以内,表观摩尔吸光率分别为5.93×104L·mol-1·cm-1(正吸收)、2.32×105L·mol-1·cm-1(负吸收),据此建立了测定氯霉素含量的分光光度法。方法用于氯霉素注射液及滴眼液中氯霉素的测定,回收率在98.9%~101.2%之间,相对标准偏差(n=6)在0.8%~1.2%之间。

In Tris-HCl buffer solution of pH 9.66, an ionic association complex was formed by the reaction of chloramphenicol with acid chrome blue K, having its positive absorption maxmum at the wavelength of 498 nm and negative absorption maximum at 594 nm. Ranges of linearity and values of apparent molar absorptivity found at both absorption maxima were within 3.2 mg·L-1 and 3.9 mg·L-1, with their values of apparent molar absorptivity of 5.93×104L· mol-1·cm-1 and 2.32×105L· mol-1·cm-1 respectively. Based on these facts, a method of spectrophotometric determination of chloramphenicol was proposed, and applied to the determination of chloramphenicol in chloramphenicol injections and eye drops, giving values of recovery and RSD′s (n=6) in the ranges of 98.9%-101.2% and 0.8%-1.2% respectively.