Fabrication of Cellulose Nanocrystal/Chitosan Hydrogel for Controlled Drug Release.

Qinghua Xu,Yunzhong Ji,Liqiang Jin,Yingjuan Fu,Qiucun Sun,Yongjian Xu

doi:10.3390/nano9020253

Abstract

In this work, a novel nanocomposite hydrogel based on cellulose nanocrystal (CNC) and chitosan (CS) was fabricated and applied as a carrier for the controlled delivery of theophylline. CNC was firstly periodate-oxidized to obtain dialdehyde nanocellulose (DACNC). Then, chitosan was crosslinked using DACNC as both the matrix and crosslinker in different weight ratios, to fabricate CNC/CS composites. The prepared composites were characterized using Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction pattern (XRD), scanning electron microscopy (SEM), zeta potential measurement and swelling ratio tests. FT-IR results confirmed the successful reaction between the free amino groups on chitosan and the aldehyde groups on DACNC. With the increase of chitosan percentage in the hydrogel, the isoelectric point was shifted towards an alkaline pH, which was probably caused by the higher content of free amino groups. The swelling ratio of the composite also increased, which may have been due to the decrease of crosslinking density. Because the swelling ratio of the drug-loaded hydrogels differed under varied pH values, the cumulative drug release percentage of the composite hydrogel was achieved to approximately 85% and 23% in the gastric (pH 1.5) and intestinal (pH 7.4) fluids, respectively. Therefore, CNC/CS hydrogel has application potential as a theophylline carrier.

Highlights

Environmental intelligent hydrogels have attracted extensive interest in biomedical fields, such as tissue engineering, biosensors, and drug delivery [1,2]
The results showed that the incorporation of bacterial cellulose (BC) matrix to load tetracycline hydrochloride (TCH) was able to control the release
The isoelectric point and swelling ratio increased with the increase of the chitosan percentage in the composites

Summary

Introduction

Environmental intelligent hydrogels have attracted extensive interest in biomedical fields, such as tissue engineering, biosensors, and drug delivery [1,2]. Chitosan is the second most abundant biomaterial on the earth, which is obtained by N-deacetylation of chitin [3]. It is nontoxic, biocompatible, biodegradable, and antibacterial in nature. These properties have led to significant research towards biomedical and pharmaceutical applications [4,5,6,7], such as drug delivery, tissue engineering, wound care dressing etc. The poor mechanical strength and poor stability in acidic aqueous solution greatly limits the applications of chitosan [8]

Methods

Results

Conclusion