Risby T H, Sehnert S S
Department of Environmental Health Sciences, The Johns Hopkins University School of Hygiene and Public Health, Baltimore, MD 21205, USA.
Free Radic Biol Med. 1999 Dec;27(11-12):1182-92. doi: 10.1016/s0891-5849(99)00212-9.
Isolation and quantification of volatile breath biomarkers indicative of relevant alterations in clinical status has required development of new techniques and applications of existing analytical chemical methods. The most significant obstacles to successful application of this type of sample have been reduction in required sample volume permitting replicate analysis (an absolute requirement for all clinical studies), separation of the analyte(s) of interest from background molecules, water vapor and other molecules with similar physical properties, introduction of automation in analysis and the use of selective detection systems (electron impact mass spectrometry, flame photometric, thermionic detectors), and automated sample collection from the human subject. Advances in adsorption technology and trace gas analysis have permitted rapid progress in this area of clinical chemistry.
分离和定量指示临床状态相关变化的挥发性呼吸生物标志物需要开发新技术以及应用现有的分析化学方法。成功应用这类样本的最主要障碍包括：减少所需样本体积以进行重复分析（这是所有临床研究的绝对要求）；将目标分析物与背景分子、水蒸气及其他物理性质相似的分子分离；在分析中引入自动化并使用选择性检测系统（电子轰击质谱、火焰光度法、热离子检测器）；以及从人体受试者自动采集样本。吸附技术和痕量气体分析的进展使得临床化学这一领域取得了快速进展。
