Poly(L-histidine)-tagged 5-aminolevulinic acid prodrugs: new photosensitizing precursors of protoporphyrin IX for photodynamic colon cancer therapy.

ABSTRACT:

Background

5-Aminolevulinic acid (ALA) and its derivatives have been widely used in photodynamic therapy. The main drawback associated with ALA-based photodynamic therapy (ALA-PDT) and ALA fluorescence diagnosis results from the hydrophilic nature of ALA and lack of selectivity for tumor versus nontumor cells. The application of certain triggers, such as pH, into conventional sensitizers for controllable (1)O(2) release is a promising strategy for tumor-targeted treatment.

Methods

A series of pH-sensitive ALA-poly(L-histidine) [p(L-His)(n)] prodrugs were synthesized via ring opening polymerization of 1-benzyl-N-carboxy-L-histidine anhydride initiated by the amine hydrochloride group of ALA itself. As an alternative to ALA for PDT, the synthesized prodrugs were used to treat

SUBMITTER: Johnson RP 

PROVIDER: S-EPMC3367496 | biostudies-literature | 2012

REPOSITORIES: biostudies-literature