Bioresponsive Materials for Drug Delivery Based on Carboxymethyl Chitosan/Poly(γ-Glutamic Acid) Composite Microparticles.

Yanghe Mo,Peng Li,Huaiyu Feng,Xiaosai Qu,Zongrui Tong,Xiaoting Yan,Shaohua Jin,Yu Chen

doi:10.3390/md15050127

Abstract

Carboxymethyl chitosan (CMCS) microparticles are a potential candidate for hemostatic wound dressing. However, its low swelling property limits its hemostatic performance. Poly(γ-glutamic acid) (PGA) is a natural polymer with excellent hydrophilicity. In the current study, a novel CMCS/PGA composite microparticles with a dual-network structure was prepared by the emulsification/internal gelation method. The structure and thermal stability of the composite were determined by Fourier transform infrared spectroscopy (FTIR), X-ray powder diffraction (XRD), scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS), and thermogravimetric analysis (TGA). The effects of preparation conditions on the swelling behavior of the composite were investigated. The results indicate that the swelling property of CMCS/PGA composite microparticles is pH sensitive. Levofloxacin (LFX) was immobilized in the composite microparticles as a model drug to evaluate the drug delivery performance of the composite. The release kinetics of LFX from the composite microparticles with different structures was determined. The results suggest that the CMCS/PGA composite microparticles are an excellent candidate carrier for drug delivery.

Highlights

In the past decades, various drug delivery systems have been developed to improve the releasing behaviors and effectiveness of drugs, and lower their side-effects
Carboxymethyl chitosan (CMCS)/Poly(γ-glutamic acid) (PGA) composite microparticles were prepared by ionic crosslinking using Al3+ as the crosslinker
The microparticles exhibited the excellent properties of CMCS and high hydrophilicity of PGA

Summary

Introduction

Various drug delivery systems have been developed to improve the releasing behaviors and effectiveness of drugs, and lower their side-effects. An ideal drug delivery system should be able to increase drug solubility, provide a sustained release system to avoid rapid breakdown and excessive use, and improve biodistribution [1]. Controlled-release systems based on smart bioresponsive materials have been extensively studied to delivery drugs [4]. The oral drug undergoes exposure to stomach (pH 1.0–2.5), duodenum (pH 6), and terminal ileum (pH 7.4) environments. Drugs encapsulated in pH-sensitive carriers should survive the harsh microenvironment in the stomach prior to entering the small intestine [5,6]. An ideal drug carrier should be biocompatible and biodegradable [7,8]

Methods

Results

Conclusion