SPME-GC-NPD法测定肉制品中挥发性N-亚硝胺的条件优化

Optimization of Extraction Conditions for the Determination of Volatile N-Nitrosamines in Meat Products Using Solid-Phase Microextraction Combined with Gas Chromatography with Nitrogen-Phosphorus Detection

利用固相微萃取(solid-phase microextraction,SPME)结合气相色谱-氮磷检测器(gas chromatographynitrogen-phosphorus detector,GC-NPD)测定肉制品中9种挥发性N-亚硝胺。通过优化平衡时间、解析时间、萃取时间、萃取温度、Na Cl浓度和转速确定9种挥发性N-亚硝胺的最佳萃取条件。结果表明:以PDMS/DVB/CAR为萃取头,平衡时间10 min、萃取温度40℃、萃取时间30 min、搅拌速率400 r/min、Na Cl质量浓度0.36 g/mL、解吸时间3 min时能得到最佳萃取效果。采用SPME结合GC-NPD测定9种N-亚硝胺的线性相关系数为0.994 9~0.999 7,检出限为0.01~10.00 ng/mL,定量限为0.03~33.00 ng/mL,回收率为50.19%~93.20%,相对标准偏差(relative standard deviation,RSD)为2.29%~9.65%。该方法可以满足肉制品中N-二甲基亚硝胺(N-nitrosodimethylamine,NDMA)、N-二乙基亚硝胺(N-nitrosodiethylamine,NDEA)、N-二丙基亚硝胺(N-nitrosodipropylamine,NDPA)和N-二丁基亚硝胺(N-nitrosodibutylamine,NDBA)这4种物质含量的测定。

Nine volatile N-nitrosamines in meat products were extracted by solid-phase microextraction（SPME） and determined by gas chromatography with nitrogen-phosphorus detection（GC-NPD）.The optimum extraction conditions were established as follows：using PDMS/DVB/CAR fiber,equilibrium time 10 min,extraction time 30 min,extraction temperature 40 ℃,stirring speed 400 r/min,concentration of NaCl 0.36 g/mL,and desorption time 3 min.The linear correlation coefficients for the nine analytes were 0.994 9-0.999 7.The limits of detection were 0.01-10.00 ng/mL,and the limits of quantification were 0.03-33.00 ng/mL.The recoveries of the presented method were in the range of 50.19%-93.20%,with relative standard deviation（RSD） of 2.29%-9.65%.In conclusion,the method could be used for the determination of N-nitrosodimethylamine（NDMA）,N-nitrosodiethylamine（NDEA）,N-nitrosodipropylamine（NDPA）,and N-nitrosodibutylamine（NDBA） in meat products.