Dendrimers with the protocatechuic acid building block for anticancer drug delivery

Protocatechuic acid (3,4-dihydroxybenzoic acid; PCA) is a well-known antioxidant compound and a potential antitumor drug that is commonly found in fruits and vegetables. This article describes the development of novel biodegradable dendrimers that contain PCA as a building block. The structures of the dendrimers were characterized by nuclear magnetic resonance, gel permeation chromatography, and matrix-assisted laser-desorption ionization time-of-flight mass spectrometry. PCA dendrimers could serve as potential anticancer drugs and also as nanocarriers for anticancer drug delivery. PCA dendrimers can easily be loaded with hydrophobic drugs such as doxorubicin that benefit from the binding interaction between PCA and the drug. Doxorubicin-loaded PCA dendrimers exhibited pH and redox-dual responsive drug release in vitro. The antitumor effect of PCA dendrimers to which polyethylene glycol polymer chains have been attached and doxorubicin-loaded dendrimers was preliminarily evaluated both in vitro and in vivo.