高效液相色谱-电喷雾离子阱质谱联用测定尿中的8-羟基脱氧鸟嘌呤

Determination of 8-Hydroxy-2′-deoxyguanosine in Urine by High Performance Liquid Chromatography-Electrospray Ionization Trap Mass Spectrometry

建立了尿样中8-羟基脱氧鸟嘌呤的HPLC—MS测定方法。尿样中的8-羟基脱氧鸟嘌呤采用WCX固相萃取小柱预富集后，以0．5％甲酸-甲醇洗脱，吹干后用0．5mL流动相溶解剩余物上机测定。采用分子的二级碎片，方法在5．0～500．0μg／L范围内呈良好线性关系，相关系数r=0．9994，检出限（S／N：3）为0．50μg/L。尿样在40．0、100．0μg/L加标水平的回收率分别为82％和76％，尿样中内源性杂质对分子二级碎片离子峰无干扰。方法具有较高的选择性和灵敏度，适合尿样等复杂基体中8-羟基脱氧鸟嘌呤的定性定量检测。

A high-performance liquid chromatography - electrospray ionization trap mass spectrometric method was established for the determination of 8-hydroxy-2＇-deoxyguanosine（8-OHdG） in urine. The sample was concentrated with WCX cartridge column and eluted out with 0. 5% finnic acid - methanol. The elute solution was evaporated to dryness in N2 flow and redissolved with 0.5 mL mobile phase. The analysis of 8-OHdG was carried out using fragment ion of m/z 116 and 167.4 as qualitative ions, and m/z 167.4 as quantitative ion. The method showed good linearity over the range of 5.0 - 500.0 μg/L for 8-OHdG with a correlation coefficient of 0. 999 4. The detection limit （S/N = 3 ） was 0. 50 μg/L. The spiked recoveries of 8-OHdG at two concentration levels of 40.0 μg/L and 100.0 μg/L were 82% and 76% , respectively. The proposed method was suitable for the determination of 8-OHdG in urine sample with high selectivity and sensitivity.