Development of metal-substituted water-soluble chlorophyll protein constructs for cancer photodynamic therapy

This study aims to enhance water-soluble chlorophyll protein (WSCP) constructs for cancer photodynamic therapy (PDT) by utilizing metal-substituted chlorophylls. While WSCPs are known to improve the water-solubility and stability of chlorophylls, this work investigates the central metal-ion substitution to further enhance photosensitizing capability and photostability. Among the tested metals, the zinc-substituted WSCP demonstrated the most successful reconstitution. Comparative analysis revealed that this zinc-substituted construct possesses superior photostability and singlet oxygen generation compared to both the native chlorophyll WSCP and the standard photosensitizer chlorin e6 (Ce6). These findings establish zinc-substituted WSCP as a promising candidate for cancer PDT applications.