Cellulose-Silk Fibroin Composite Particles for Hydrophilic Drug-Controlled Release System: Preparation and Characterization

Abstract

The objective of this study was to investigate the dissolution of cellulose (C) powder as a potential material for particle formation when combined with a silk fibroin (SF) solution. Each polymer solution as well as a mixture of cellulose and silk fibroin in different ratios were prepared into particles using the solvent emulsion-diffusion method. The particle morphology was characterized by scanning electron microscopy (SEM) and by attenuated reflection Fourier-transformed infrared spectroscopy (ATR-FTIR) and thermogravimetric analyzer (TGA) for the C-SF molecular interaction and thermal properties, respectively. The results showed that the cellulose particles appeared as separate fibers and loosely bound together, while silk fibroin particles were spherical in shape with dense texture and smooth surface. The C/SF mixed particles with different ratios could be formed into spherical particles and a ratio of 1:3 has the most spherical and solid. The ATR-FTIR results indicated the absorption spectra of the main functional groups both cellulose and silk fibroin. Blue dextran helped to enhance the temperature of the maximum decomposition rate (Td,max) of the particles via hydrogen bond interaction between the blue dextran and polymers. A burst release of blue dextran was observed in the first 12 h due to the swelling of particle surfaces and the slowest release found in the silk fibroin particles. The C/SF composite showed different blue dextran- eleased profiles and the particle with a high content of silk fibroin-released blue dextran in slowly rate. The results of this work can be used as a basis for applying C/SF composite particles in a hydrophilic drug release-controlled system.