Biophotonics is an interdisciplinary field that combines photonics (light-based technologies) with biology and medicine to study biological systems, diagnose diseases, and develop advanced therapies. It leverages the unique properties of light (e.g. precision, non-invasiveness, and high resolution) to explore and manipulate living tissues at the molecular, cellular, and systemic levels.

Core Principles of Biophotonics

Light-Matter Interactions in Biology

Biophotonics exploits how light interacts with biological tissues, including

Absorption (e.g. haemoglobin, melanin).

Scattering (due to cell structures).

Fluorescence (natural or labelled molecules).

Raman scattering (vibrational fingerprinting).

Key Technologies

Lasers (for precision surgery, imaging, stimulation).

Optical fibres (endoscopy, biosensors).

Nanophotonics (plasmonics, quantum dots for sensing).

Non-linear optics (multiphoton microscopy).

Major Applications of Biophotonics

Medical Imaging & Diagnostics

Confocal & Multiphoton Microscopy

High-resolution 3D imaging of live cells/tissues.

Optical Coherence Tomography (OCT)

Label-free molecular fingerprinting (e.g. cancer detection).

Fluorescence Imaging

Tracks biomarkers (e.g. GFP-tagged proteins).

Therapy & Surgery

Laser Surgery

Precision cutting/ablation (e.g. LASIK, tumour removal).

Photodynamic Therapy (PDT)

Light-activated drugs kill cancer/bacteria.

Low-Level Laser Therapy (LLLT)

Promotes wound healing and pain relief.

Neurophotonics & Optogenetics

Optogenetics: uses light-sensitive proteins (e.g. Channelrhodopsin) to control neurons.

Fibre optic brain probes: monitor neural activity in real time.

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