HPLC法测定牙膏中银杏叶提取物总黄酮苷的含量

以槲皮素、山奈素和异鼠李素为指标，建立HPLC法测定牙膏中银杏叶提取物总黄酮苷的含量。采用Agilent ZORBAX Eclipse XDB-C18色谱柱（Analytical 4．6×250mm 5-Micron）；流动相为甲醇-0．4％磷酸（55／45，V/V）；流速为1．0mL／min；检测波长为360nm；柱温为40℃；进样量为20μL。结果表明，槲皮素、山奈素和异鼠李素浓度分别在2．1～21．0、1．8～18．0和0．42～4．2μg／mL范围内呈良好的线性关系，相关系数分别为：0．9999、0．9999和0．9998；槲皮素、山奈素和异鼠李素回收率分别为：97．7％、98．3％和97．6％。该方法简单、灵敏、准确，可用于牙膏中银杏叶提取物总黄酮苷含量的测定。

Determination of Total Flavonoids from the Extract of Ginkgo Leaf in Toothpaste by HPLC

To establish a method for determining total flavonoids from the extract of Ginkgo leaf in toothpaste by HPLC, with the indices of quereetin, kaempferol and isorhamnetin. Method： Agilent ZORBAX Eclipse XDB-C18 column （Analytical 4.6 × 250 mm5-Micron）, mobile phase： V（MeOH） ： V（0.4% H3PO4） = 55 ： 45; flow rate： 1.0 mL/min; λ= 360 nm; column temperature： 40℃ ; sample volume：20 μL. Results showed that the calibration curve of quercetin, kaempferol and isorhamnetin were linear in range of 2.1-21.0 μg/mL, 1.8-18.0 μg/mL and 0.42-4.2 μg/mL, respectively; correlation coefficients were 0. 9999, 0. 9999 and 0. 9998; the absolute recoveries of quereetin, kaempferol and isorhamnetin were 97. 7%, 98. 3% and 97.6%. This method is easy, flexible and exact for determination of total flavonoids from the extract of Ginkgo leaf in toothpaste.