Emerging optical spectroscopy techniques for biomedical applications-A brief review of recent progress

Optical measurement methods are widely employed in both industrial and medical fields for two reasons: (1) they are non-invasive and (2) they have a high resolution. Among the various optical methods currently available, those based on spectroscopy are actively employed to monitor multiple factors using spectral information. In this review article, three categories of optical spectroscopic methods for biomedical diagnosis are discussed: (1) in vitro preclinical diagnosis using optical spectroscopy, (2) non-invasive early-stage diagnosis based on optical spectroscopy at the surface of the skin and (3) minimally-invasive diagnosis using spectroscopy-integrated endoscopies. We also highlight the advances in nanomaterials, molecular probes, and photonic system constructions that have led to improvements in the sensitivity, diagnostic speed, and capability to analyze multiple medical parameters. Additionally, we briefly discuss the future prospects of these spectroscopic applications and the combination of optical techniques with information technology.