Work

Monitoring the accumulation and photobleaching of protoporphyrin IX and photo-protoporphyrin during photodynamic therapy under dual-wavelength fluorescence excitation

Year: 2025

Type: article

Abstract: Significance Studying kinetics of PpIX accumulation in tissue helps identify optimal time intervals for PDT based on PS and photoproduct concentrations, optimizing irradiation. Ppp photoproducts exhibit photodynamic activity, allowing Ppp consideration as an additional photosensitizer that enhances therapeutic effect. Approach Study involved optical phantoms simulating skin properties with accumulated PpIX, two patients with skin neoplasms. PDT used 20% aqueous 5-ALA solution prepared before administration. Spectral fluorescence diagnostics employed lasers (405 nm, 632.8 nm), spectrometer, and Y-shaped optical fiber. PDT used lasers (635 nm, 660 nm). Photoproducts formation was analyzed using 405 nm and 660 nm lasers. Results PDT with 635 nm irradiation led to photoporphyrin formation in studied areas. Fluorescence intensity of photoporphyrins declined slower than PpIX. Under 660 nm excitation, photoproduct fluorescence decreased significantly. Conclusions Monitoring photoproduct formation is crucial for improving 5-ALA PDT efficiency. Differences in PpIX accumulation dynamics between superficial and deeper tissue layers enhance diagnostics accuracy and PDT precision.

Source: Photodiagnosis and Photodynamic Therapy

DOI: 10.1016/j.pdpdt.2025.105074

Authors: Daniil Kustov, Kanamat Efendiev, Vera Zavedeeva, Lyudmila Loschenova, Victor Loschenov

Institutions: Prokhorov General Physics Institute, Sorbonne Université, National Research Nuclear University MEPhI

Language: English

Topic: Photodynamic Therapy Research Studies

Subfield: Pulmonary and Respiratory Medicine

Field: Medicine

Domain: Health Sciences

SDG: Good health and well-being

Open Access status: gold

Estimated APC paid: $2,610