Biophotonics

Biophotonics is the science and technology of using light-based methods to study, image, and manipulate biological systems. It combines biology, medicine, physics, chemistry, and engineering to interrogate living tissues at microscopic and molecular scales. Through wavelengths from the visible to the near-infrared, biophotonics relies on the interactions of light with biological matter, including absorption, scattering, fluorescence, and refractive index changes.

Core techniques include optical imaging modalities such as fluorescence and confocal/multiphoton microscopy, two-photon and super-resolution methods; optical coherence tomography; diffuse optical tomography; and light-sheet microscopy. Spectroscopic approaches—fluorescence lifetime, Raman, surface-enhanced Raman spectroscopy (SERS), and infrared spectroscopy—provide chemical and functional information. In vivo imaging uses bioluminescence and fluorescence reporters; optogenetics uses light to control cellular activity. Therapeutic applications include photodynamic therapy and photothermal therapy, as well as laser-assisted surgeries and minimally invasive interventions.

Applications span biomedicine, diagnostics, drug discovery, neuroscience, ophthalmology, dentistry, agriculture, and environmental sensing. Biophotonics plays a key role in image-guided surgery and point-of-care diagnostics; it is also used in basic research to study cellular processes, gene expression, and tissue engineering. The field emphasizes safety, data analysis, and image processing, with developments in fiber optics, nanoscale photonics, and portable devices. As a multidisciplinary area, biophotonics continues to evolve with advances in nanotechnology, machine learning–driven analysis, and new light–matter interaction regimes.