金属有机框架复合材料分子印迹-高效液相富集和检测红花样品中的胭脂红

HPLC using capillary monolithic column molecularly imprinted with composite metal organic frame for enrichment and detection of Ponceau 4R in Carthami flos

目的制备分子印迹掺杂金属有机框架(UiO-66-NH2)的毛细管整体柱,并将其与高效液相联合应用于红花样品中胭脂红的富集、除杂和检测。方法通过原位聚合法制备掺杂UiO-66-NH2的分子印迹毛细管整体柱(UiO-66-NH2@MIPs整体柱)并利用高效液相、扫描电子显微镜和红外光谱等分析手段对分子印迹毛细管整体柱的吸附性能和形态特征进行表征,然后联用高效液相对红花实际样品中的胭脂红进行检测分析。结果通过UiO-66-NH2@MIPs整体柱-高效液相法,胭脂红在0.1~10.0μg/mL(R2=0.9999)范围内有良好的线性,检测限(S/N=3)为2.7×10-4μg/mL,红花样品中胭脂红的平均回收率为82.60%~105.56%,日间和日内相对标准偏差(RSD)均在2.4%~3.4%。其中UiO-66-NH2@MIPs整体柱的柱容量为0.178μg/mg,明显优于其它3类自制毛细管整体柱(分别为0.089、0.080、0.111μg/mg)。在优化条件后,红花样品中胭脂红经UiO-66-NH2@MIPs整体柱-高效液相检测的富集倍数为直接通过高效液相检测的73倍,同时还有明显除杂效果以减少其它杂质峰的影响。结论自制的UiO-66-NH2@MIPs整体柱-高效液相法其富集、除杂和检测效果明显优于直接通过高效液相检测,因此我们成功研制了一种灵敏度高、价格低廉、操作简单的新方法检测红花样品中的胭脂红。

Objective To assess the performance of high-performance liquid chromatography(HPLC)combined with capillary monolithic column molecularly imprinted with metal organic frame(UiO-66-NH2@MIPs capillary monolithic column)for enrichment,purification and detection of Ponceau 4R in Carthami flos.Methods UiO-66-NH2@MIPs monolithic columns were prepared via in situ polymerization,and the adsorption properties and morphology of the columns were characterized by HPLC,scanning electron microscopy(SEM)and infrared(IR)spectral analysis.HPLC with the prepared columns was performed for detecting the content of Ponceau 4R in Carthami flos samples.Results The UiO-66-NH2@MIPs system showed a good linearity for detecting Ponceau 4R over the concentration range of 0.1-10.0μg/mL with a correlation coefficient>0.9999 and a detection limit(S/N=3)of 2.7×10-4μg/mL.The mean recovery of Ponceau 4R in Carthami flos samples ranged from 82.60%to 105.56%,and the intra-day and inter-day relative standard deviation(RSD)values ranged from 2.4%to 3.4%.The recycling experiment showed that the system could be reused for sensitive detection of Ponceau 4R in Carthami flos.The capacity of UiO-66-NH2@MIPs column was 0.178μg/mg,which was superior to that of other monolithic columns(0.089,0.080,and 0.111μg/mg),demonstrating that the addition of UiO-66-NH2 increased the adsorption capacity of the system.Under the optimized conditions,the UiO-66-NH2@MIPs-HPLC system had an enrichment factor of over 73 folds with obviously reduced interference by the impurity peaks.Conclusion The UiO-66-NH2@MIPs column-HPLC system has much better performance for enrichment,purification and detection of Ponceau 4R in Carthami flos than direct HPLC.