两种比色法测定何首乌中游离蒽醌含量的比较

[目的]选择测定何首乌中游离蒽醌含量的方法.[方法]精密称定何首乌药材适量,氯仿超声萃取,取部分溶液蒸干,残渣分别用混合碱比色法和醋酸镁比色法进行测定.[结果]醋酸镁比色法的测定值在16 h内稳定,RSD为0.87%,平均回收率为99.37%±1.35%,同一样品5次测定的RSD为1.02%;混合碱比色法16 h时的RSD为2.83%,平均回收率为96.72%±1.57%,同一样品5次测定的RSD为4.86%.[结论]醋酸镁比色法适用于何首乌中游离蒽醌含量的测定,且具有稳定、准确及重现性好等特点.

Comparison of content of anthraquinone in the Radix Polygoni Multiflori by two spectrophotometric methods

OBJECTIVE To select the spectrophotometric method for determining the content of anthraquinone in the Radix Polygoni Multiflori. METHODS The proper Radix Polygoni Multiflori powder was weighted accurately,and then the anthraquinone content was collected by ultrasonic with chloroform.Part of collected liquid was evaporated and the remainder was measured by mixed alkali and magnesium acetate methanol colorinetry spectrophotometric method. RESULTS The data of magnesium acetate-methanol colorinetry pectrophotometric method was stable in 16 h(the RSD was 0.87%),recovery was 99.37%±1.35%,RSD was 1.02% when the same sample was measured in 5 times,the data of mixed alkali colorinetry spectrophotometric method was 2.83%,96.72%±1.57%,4.86% in turn. CONCLUSION The magnesium acetate-methanol colorinetry spectrophotometric method is propitious to detect the content of anthraquinone in the Radix Polygoni Multiflori and has characteristics of stable,accurate and recurrence.