Advances in 5-aminoketovaleric acid(5-ALA) nanoparticle delivery system based on cancer photodynamic therapy

Photodynamic therapy (PDT) is a novel therapy that achieves therapeutic effects by exciting photosensitizers accumulated in tumour tissues with specific wavelengths of light. Among the various photosensitizers, 5-aminoketovaleric acid (5-ALA) has been used in the treatment of basal cell carcinoma, glioma, bladder cancer, and other tumours owing to its safety and economy. However, the efficacy of PDT is limited by the poor permeability and targeting of 5-ALA, and favourable nano-delivery systems would provide ideal platforms to solve this problem. Researchers have developed a variety of 5-ALA nano-delivery systems, such as nanoparticles, liposomes, and gels, and have achieved good efficacy in the treatment of various tumours. In this review, we present the progress of 5-ALA nano-delivery systems in different oncology fields and discuss the current challenges and future research prospects.