顶空固相微萃取-气相色谱质谱法测定人体足部气味中短链脂肪酸

Determination of short-chain fatty acids in foot odor by head space solid phasemicroextraction coupling gas chromatography mass spectrometrometry

短链脂肪酸是人体足部气味物质的主要组成部分,建立合理的方法分析其含量分布有助于揭示人体代谢物与足部微生物之间的作用机制,可为足部除味提供有效的技术支撑.建立了顶空固相微萃取(HS-SPME)-气相色谱质谱法(GC-MS)测定人体足部丙酸、异丁酸、丁酸、异戊酸、己酸和庚酸6种短链脂肪酸的分析方法.通过优化SPME萃取条件,获得了最佳萃取参数,萃取时间20 min,萃取温度50℃,解析时间2 min.在最佳条件下对6种短链脂肪酸萃取分析,方法线性范围为0.25~50.00 ng(0.9412≤R^(2)≤0.9972);加标回收率为92.50%~120.90%;检出限为0.017~0.096 ng;方法定量限在0.06~0.32 ng之间;RSD(n=9)均小于20%.对10名志愿者足部进行了分析,获得了满意的结果.

Short-chain fatty acids are main components of human foot odor.Development of methodology for analyzing the content of short-chain fatty acids could help to reveal the mechanism between human metabolites and foot microbes.Furthermore,it can contribute to deodorization research of the feet.In this paper,a headspace solid-phase microextraction(HS-SPME)couping gas chromatography-mass spectrometry(GC-MS)method was developed for determination of propionic acid,isobutyric acid,butyric acid,isovaleric acid,hexanoic acid and heptanoic acid in human foot odor.The extraction conditions were investigated,with resulting that the optimum conditions for SPME were 20 min for extraction time,50℃for extraction temperature and 2 min for desorption time.The linear range of six short-chain fatty acids for developed method was 0.25~50.00 ng(0.9412≤R^(2)≤0.9972),recovery was from 92.5%to 120.9%.The limit of detection was 0.017~0.096 ng,and limit of quantitation ranged from 0.06 to 0.32 ng.RSD(n=9)was less than 20%for all studied short-chain fatty acids.This method was applied in foot odor analysis of 10 volunteers and satisfactory results were obtained.