ZIF-8泡腾辅助分散固相萃取结合高效液相色谱-串联质谱法测定人尿液中苯二氮卓类药物

Determination of Benzodiazepines in Human Urine Sample by HPLC-MS/MS Combined with ZIF-8 Based Effervescent Tablet-assisted Dispersive Solid-phase Extraction

发展了基于沸石咪唑酯骨架材料-8(ZIF-8)的泡腾辅助分散固相萃取(ET-DSPE)技术,结合高效液相色谱-串联质谱法(HPLC-MS/MS)对人尿液中艾司唑仑、阿普唑仑、地西泮、三唑仑和劳拉西泮5种苯二氮卓类药物(BZDs)进行分析。采用傅里叶变换红外光谱、X射线衍射仪、扫描电子显微镜和全自动比表面积及孔隙分析仪对ZIF-8进行表征,并考察了ZIF-8和Na_(2)CO_(3)用量、吸附时间、溶液pH值及离子强度、尿液稀释比例、洗脱溶剂、洗脱体积和时间对BZDs萃取效率的影响。在最佳条件下,艾司唑仑在0.002~100 ng/mL,其余4种BZDs在0.001~100 ng/mL范围内线性关系良好(r≥0.999),检出限和定量下限分别为0.0003~0.0006 ng/mL和0.001~0.002 ng/mL,3个加标水平下的回收率为81.6%~108%,日内和日间相对标准偏差分别为1.4%~5.6%和1.4%~9.9%。该方法不仅能够直接处理原始尿液,无需稀释和去蛋白操作,而且通过泡腾辅助分散,对BZDs的富集倍数达40.8~54.0倍,实现了尿液中5种BZDs的准确、简便和灵敏分析。

In this study,zeolitic imidazolate framework-8(ZIF-8)based on effervescent tablet-assisted dispersive solid-phase extraction method(ET-DSPE)was developed and coupled with high performance liquid chromatography tandem mass spectrometry(HPLC-MS/MS)for the determination of five benzodiazepines(BZDs)in human urine samples,including estazolam,alprazolam,diazepam,triazolam and lorazepam.The prepared ZIF-8 sorbent was characterized by Fourier transform infrared spectroscopy,X-ray powder diffractometry,scanning electron microscopy,automatic specific surface area and pore analyzer,and the results showed that ZIF-8 nanoparticles with rhombohedral dodecahedral structure were successfully synthesized.The extraction parameters of the adsorption and elution processes were optimized in detail,involving amount of ZIF-8 sorbent and Na_(2)CO_(3),adsorption time,pH and ionic strength of solution,urine dilution ratio,elution solvent,elution volume and time.The optimal conditions were shown as follows:ZIF-8 amount,35 mg;Na_(2)CO_(3)amount,20 mg;adsorption time,4 min;pH and ionic strength of the solution,no adjustment;urine dilution ratio,no dilution;elution,1.0 mL of methanol;elution time,30 min.Under the optimized conditions,the proposed method provided the linear ranges of 0.002-100 ng/mL for estazolam and 0.001-100 ng/mL for the other four analytes(r≥0.999).The limits of detection(S/N=3)and the limits of quantification(S/N=10)of five BZDs were in the ranges of 0.0003-0.0006 ng/mL and 0.001-0.002 ng/mL,respectively.Besides,the recoveries for spiked urine samples with three concentration levels varied from 81.6%to 108%with the intra-day relative standard deviations(RSDs)and inter-day RSDs of 1.4%-5.6%and 1.4%-9.9%separately.Compared with the previous pretreatment methods for BZDs in urine samples,ZIF-8 based effervescent tablet-assisted dispersive solid-phase extraction method allowed direct loading of crude urine samples without any filtration or dilution step.Besides,the effervescent tablet-assistance facilitated a well dispersion and an adequate adsorption,offering the enhancement factor of 40.8-54.0.The developed method achieved a strategy for the accurate,convenient and sensitive determination of five BZDs in human urine samples.