Mid-infrared absorption spectroscopy with enhanced detection performance for biomedical applications

Mid-infrared absorption spectroscopy is a powerful tool to measure and analyze composition, concentration and structure of substance molecules. Due to the advantages of noninvasive, label-free and real time, it is widely used to assist analysis and diagnosis in the biomedical field. In order to meet the analysis demand of low concentration clinical samples, the limit of detection (LOD) needs to be continuously enhanced. In this study, typical enhancement technologies for mid-infrared absorption spectroscopy are reviewed, including tunable diode Laser absorption spectroscopy (TDLAS), dual-comb absorption spectroscopy (DAS), cavity enhanced spectroscopy, hollow waveguide absorption spectroscopy (HWGAS), surface enhancement infrared absorption (SEIRA), and photoacoustic spectroscopy (PAS). Particular attention is paid to the application of these enhancement technologies in the biomedical field of breath analysis, body fluid detection, structure and conformational transition of proteins, food and drug quality monitoring. This review provides a comprehensive technology reference of mid-infrared absorption spectroscopy, as well as discussions on its application aspects in biomedical field.