响应面-Box-Behnken设计优化地参中总黄酮含量检测方法以及不确定度评定

Response surface-Box-Behnken design to optimize detection method and uncertainty evaluation of total flavonoids in Lycopus lucidus

为优化地参总黄酮含量测定方法,该研究比较了NaNO_(2)-Al(NO_(3))_(3)-NaOH、AlCl_(3)-KAc和三乙胺3种显色体系中6种对照品及供试品的吸收光谱曲线,对NaNO_(2)-Al(NO_(3))_(3)-NaOH体系显色剂加入量对总黄酮测量结果的影响进行了响应面-Box-Behnken设计优化,并对供试品溶液的制备,对照品溶液的制备,显色体系和标准曲线拟合进行了不确定度评估,计算合成不确定度并给出测量结果的扩展不确定度和置信水平。通过适应性分析,试验最终选择了NaNO_(2)-Al(NO_(3))_(3)-NaOH显色体系,最佳显色条件为50 g/L硝酸钠0.9 mL,100 g/L硝酸铝0.6 mL,1 moL/L氢氧化钠4.8 mL,显色温度42℃,以芦丁为标准品,在该条件下测得地参总黄酮含量为(91.052±2.75) mg。确定了地参总黄酮含量测定的最佳体系为NaNO_(2)-Al(NO_(3))_(3)-NaOH显色体系,及该体系下最佳测定条件,为地参总黄酮的测定提供了新的参考方法。

To optimize the determination method for the total flavonoids in Lycopus lucidus,this study compared the absorption spectra of 6 reference substances and the samples in the three color reaction systems of NaNO_(2)-Al(NO_(3))_(3)-NaOH,AlCl 3-Kac,and triethylamine.The response surface-Box-Behnken design optimization was carried out to optimize the influence of the color reagent dosage on the measurement results of total flavonoids in color reaction system of NaNO_(2)-Al(NO_(3))_(3)-NaOH.The uncertainty evaluation of the preparation of the test solution,the preparation of the reference solution,the color reaction system,and the standard curve fitting was carried out.The combined uncertainty also was calculated,and the expanded uncertainty and the confidence level of the measurement result were given.Through adaptability analysis,NaNO_(2)-Al(NO_(3))_(3)-NaOH color reaction system was finally selected in the experiment,and the optimal color reaction conditions were as follows:0.9 mL of 50 g/L sodium nitrite,0.6 mL of 100 g/L aluminum nitrate,4.8 mL of 1 moL/L hydrogen sodium oxide,and color reaction temperature was 42℃.The content of total flavonoids was measured at(91.052±2.75)mg under optimal conditions,which provided a new reference method for the determination of total flavonoids.