QuEChERS提取-超高效液相色谱-串联质谱法测定腐败人血中3种钩吻生物碱

为同时测定腐败血液中钩吻生物碱(钩吻素子、钩吻素甲和钩吻素己等3种),应用QuEChERS前处理方法提取上述3种分析物,并用超高效液相色谱-串联质谱法进行测定。取血样1.00mL,加入乙腈2mL和NaCl50mg,涡旋振荡提取20s,继续振荡10min后,以8000r·min^-1转速离心10min。取上清液,加入十八烷基硅烷(C18)20mg作为吸附剂,按上述相同方法振荡并离心,进行基质分散固相提取。取上清液按仪器工作条件进行分析。在色谱分离中,应用ZORBAXEclipsePlusC18色谱柱为固定相和不同比例的(A)乙腈和(B)含φ0.1%甲酸的5mmol·L^-1甲酸铵溶液的混合溶液为流动相进行梯度淋洗,达到上述3种钩吻生物碱的良好分离。质谱测定中选择电喷雾正离子源和多反应监测模式。3种钩吻生物碱的质量浓度在一定范围内与对应的峰面积呈线性关系,检出限(3S/N)在0.005~0.1μg·L^-1之间。在空白血样的基础上加入上述3种钩吻生物碱的混合标准溶液,并按上述方法测定求得其回收率在90.5%~110%之间,测定值的相对标准偏差(n=6)在2.1%~5.1%。

UPLC-MS/MS Determination of 3 Gelsemium Alkaloids in Putrefied Human Blood with Pretreatment by QuEChERS

Three of the gelsemium alkaloids in putrefied whole blood were pretreated by the QuEChERS approach and determined by UPLC-MS/MS. In the QuEChERS, 1.00 mL of the blood sample was extracted by swirly shaking for 20 s with 2 mL of acetonitrile and 50 mg of NaCl, and the shaking was continued for 10 min, and the mixture was centrifuged for 10 min at a rate of 8 000r·min^-1. The supernatant was taken and treated by the dispersed-matrix SPE using 20 mg of Ci8 as adsorbent and the mixture was shaken and centrifuged in the same way as described above. The supernatant was separated and used for UPLC and MS/MS analysis as described in the instrumental working conditions. The chromatographic column of ZORBAX Eclipse Plus Cig was selected as stationary phase, and mixtures of (A) acetonitrile and (B) 5 mmol·L^-1 ammonium formate (containing φ 0.1% of formic acid) in various ratios were used as mobile phase in gradient elution, to have the 3 gelsemium alkaloids wellseparated. In the MS/MS determinations, electrospray positive ion source and mode of multi-reaction monitoring were adopted in MS/MS. Linear relationships were obtained between values of peak areas and mass concentrations of the 3 gelsemium alkaloids in definite ranges, with detection limits (3S/N) in the range of 0.005 - 0.1 μg·L^-1. Recovery tests were made by addition mixed standard solutions of the 3 gelsemium alkaloids to a blank sample as matrix and then determined by the proposed method, giving values of recovery in the range of 90.5%-110%, and values of RSDs (n = 6) in the range of 2.1%-5.1%.