通过人体口呼或鼻呼均可采集呼气样本,但口腔和鼻腔环境会影响呼气组分,因此,探究口呼气和鼻呼气的成分,对理解口腔和鼻腔环境对呼气组分的影响以及选择合适的采样方式均具有重要意义.本研究采用二次电喷雾电离高分辨质谱技术(Secondary electrospray ionization-high resolution mass spectrometry,SESI-HRMS)实时在线分析呼气样品,建立了人体呼气中常见挥发性有机物(Volatile organic compounds,VOCs)2-丁酮、2-戊酮、甲苯、苯乙烯、均三甲苯、乙酸乙酯、甲基丙烯酸甲酯、异戊二烯和柠檬烯的定量分析方法.结果表明,9种VOCs的检出限(Limit of detection,LOD)在2.3～240.8 ng/m3 之间,日内和日间相对标准偏差(RSD)分别为0.6%～4.6%和4.3%～12.2%.进一步探究了口呼气与鼻呼气有机组分特征,检测到口呼气有167个特有组分,鼻呼气有76个特有组分,口呼气中特有组分数量是鼻呼气的2.2倍,推测是口腔环境更为复杂所致;另有163个组分同时存在于口呼气和鼻呼气中,其信号强度在两者中存在显著差异.上述差异分析结果表明,鼻呼气中极性化合物的比例高于口呼气,两者所含组分的种类和数量均存在显著差异,因此有必要根据研究需要采取适宜的采样方式.
Real-time Analysis of Organic Composition of Oral and Nasal Breath Air by High Resolution Mass Spectrometry
Human exhaled breath has great application prospects,e.g.,monitoring pharmacokinetics,disease diagnosis,due to its advantages such as non-invasive and high-frequency sampling.Breath samples can be collected from the oral and nasal cavity.However,the oral and nasal environment affect the chemical composition of breath sample.Therefore,the investigation on the chemical composition of mouth-exhaled breath and nose-exhaled breath is crucial for selection of appropriate sampling strategy for individual studies.In this work,secondary electrospray ionization-high resolution mass spectrometry(SESI-HRMS)was applied to analysis of respiratory metabolomics in real time.A quantitative analysis approach was established for 9 kinds of volatile organic compounds(VOCs)e.g.2-butanone,2-pentanone,ethyl acetate,methyl methacrylate,toluene,styrene,mesitylene,isoprene and limonene.The limit of detection was 2.3‒240.8 ng/m3.The intra-day(n=6)and inter-day(n=18)relative standard deviations were 0.6%‒4.6%and 4.3%‒12.2%,respectively.Nine healthy subjects were recruited to investigate the chemical composition of mouth-exhaled and nose-exhaled breath.The results showed the good performance in quantitative analysis of 9 VOCs in breath air.It was found that the number of unique component(m/z)detected in mouth-exhaled breath(167)was 2.2 times greater than that detected in nose-exhaled breath(76),which might result from the complex environment in oral cavity.The signal intensity of commun component(163)was significantly different between mouth-exhaled breath and nose-exhaled breath.Additionally,the elemental composition analysis showed that the proportion of polar compounds detected in nose-exhaled breath was higher than that in mouth-exhaled breath.This study demonstrated that there was significant differences in the chemical composition between mouth-exhaled and nose-exhaled breath,which provided a theoretical basis for selection of exhalation mode.
国家科技期刊平台
NSTL
万方数据
