固相萃取-液相色谱串联质谱仪法测定酱、腌制品中谷氨酸钠的含量及居民膳食暴露风险评估

Study of determination on content of sodium glutamate in sauce and marinated products by solid phase extraction liquid chromatography-tandem mass spectrometry and risk assessment of dietary exposure in residents

目的建立液-质联用法(HPLC-MS)检测酱、腌制品中谷氨酸钠含量及居民膳食暴露风险评估的方法。方法以纯水做为提取液,初始流动相作为复溶液,选用MAX小柱净化,对含量高的样品可直接稀释上机测定。选择用ACQUITY UPLC BEH-Hilic(100 mm×2.1 mm,1.7μm)柱子检测峰保留最好,选择优化后的色谱、质谱条件,以LC-MS/MS测定。结果该法溶液浓度范围在0.5~5.0 mg/L线性关系良好,检出限为15 mg/kg,定量限为50 mg/kg,稳定性试验相对标准偏差(RSD)为1.03%,符合试验要求;精密度试验相对标准偏差范围1.12%~6.86%,回收率范围85.6%~95.0%。对含量高的样品可直接稀释上机测定,与过净化柱检测结果差异有统计学意义(t=-2.153,P<0.05);酱、腌制品中普遍含有谷氨酸钠,总检出率为86.0%,平均含量为5.28×10^(3)mg/kg,五类酱、腌制品中谷氨酸钠的平均含量差异无统计学意义(t=1.176,P>0.05),居民摄入谷氨酸钠的平均值均低于上限(1.89×10^(3)mg)。结论该方法操作简单、分析速度快、精密度好、准确度高、重现性好,是理想的测定酱、腌制品中谷氨酸钠的方法;居民酱、腌制品中谷氨酸钠的日暴露量均处在可接受安全水平范围内。

Objective To set up the method by means of high performance liquid chromatography-mass spectrometry(HPLC-MS)for detection on the content of sodium glutamate in sauce and marinated products and that for risk assessment of dietary exposure in residents.Methods Pure water was used as the extracting solution,the initial mobile phase was used as the complex solution,MAX column was selected for purification,and the samples with high content was supported to be directly diluted to the machine for determination.ACQUITY UPLC BEH-Hilic(100 mm×2.1 mm,1.7μm)column was preferedly selected to retain the detection peak.Optimized chromatographic conditions and mass spectrometry conditions were selected for determination by LC-MS/MS.Results The concentration range of the method within 0.5-5.0 mg/L were found to have satisfactory linear relationship,the detection limit of the instrument was 15 mg/kg,the quantitative limit was 50 mg/kg,and the relative standard deviation(RSD)of stability test was 1.03%,meeting the test requirements;RSD of precision tests ranged from 1.12%to 6.86%,and the recovery rate ranged from 85.6%to 95.0%.High-content samples were supported to be directly diluted to the machine for determination,and there was significant difference from the detection results of the over-purification column(t=-2.153,P<0.05);the sodium glutamate with total detection rate of 86.0%and average content of 5.28×10^(3)mg/kg was generally detected in sauce and marinated products,there was no significant difference in the average content of sodium glutamate among five kinds of sauce and marinated products(t=1.176,P>0.05),and the mean intake of sodium glutamate in residents was lower than the upper limit(1.89×10^(3)mg).Conclusion The method is simple,fast,precise,accurate,and has good reproducibility,being an ideal method for the determination on glutamate sodium in sauce and marinated products.The daily exposure of glutamic acid from soy sauce and marinated products in residents is considered to be within acceptable safety level.