Abstract:

Objective To establish a rapid method for the analysis of bucinnazine in blood by UPLC-MS/MS and to apply the method to the practical case. Methods After the internal standard was added to blood, the protein was precipitated with 900 μL mixed solution （V_acetonitrile∶V_water=8∶2）. After vortex and centrifugation, the protein was measured through 0.22 μm filter membrane. The separation was performed on C₁₈ chromatography column, with acetonitrile and 5 mmol/L ammonium acetate containing 0.1% formic acid aqueous as mobile phase gradient elution at the flow rate of 0.4 mL/min. Multiple reaction monitoring scan was performed in electrospray positive ion mode, quantitative measurement was performed by internal standard method, and methodological verification was carried out. Results The linear relationship of bucinnazine in blood was good in the range of 0.5-200 μg/L, the correlation coefficient （r） was 0.999 7, the limit of detection was 0.1 μg/L, the limit of quantitation was 0.5 μg/L, and the recovery was 78.3%-83.8% at 1, 10 and 100 μg/L mass concentration levels. The matrix effect was 69.4%-73.8%, the intra-day precision was 1.9%-2.8%, and the inter-day precision was 2.8%-3.2%, the accuracy was 3.1%-3.5%. The stability test results of 1 and 100 μg/L mass concentrations at -25 ℃ showed that the accuracy （bias） of 10 d was less than 4.5%. Conclusion This method has the advantages of simple pre-treatment process, fast sample processing speed, high sensitivity of instrument analysis, good stability of content determination and reliable identification results, and can meet the needs of case identification.

Key words: forensic medicine, toxicological analysis, bucinnazine, blood, ultra-high performance liquid chromatography-tandem mass spectrometry （UPLC-MS/MS）