Development of a pluronic-zein-curcumin drug delivery system with effective improvement of hydrophilicity, stability and sustained-release

Abstract

Curcumin (Cur) has been widely studied for its chemo-preventive and chemotherapeutic effects against various types of human cancers, but the clinical application of curcumin is limited due to multiple delivery challenges, including poor water solubility, poor membrane permeability and easy degradation under alkaline conditions. Zein is an excellent carrier for pharmaceutical preparations because of its non-toxicity and biodegradability, but the plant protein source and hydrophobicity limit the application of zein in biomedical applications. The aim of this study is to overcome the limitations of Cur and zein in clinical therapy. To improve the hydrophilicity of zein and obtain a highly stable drug delivery system (DDS), zein was modified with carboxylated pluronic to prepare pluronic-zein (ZSP). The results indicated that the ZSP prepared not only has good hydrophilic and dispersibility properties, where the surface contact angle of the ZSP prepared is reduced by 33.1%–62.8%, but also its stability is not affected by pH and salinity compared with zein particles. After loading Cur into ZSP particles, Cur-ZSP DDS with good dispersibility and drug loading was prepared. Cur-ZSP DDS exhibited sustained release in the simulated in vitro environment. Cell experiments showed that ZSP presented as non-toxic. After loading with Cur, the cytotoxicity of Cur-ZSP DDS was significantly higher than that of raw Cur. The results provide new insight into the construction of zein-based oral drug delivery systems.