Biodegradable silk fibroin/chitosan blend microparticles prepared by emulsification-diffusion method

Abstract

Abstract:In this study, biodegradable microparticles of silk fibroin (SF)/chitosan (CS) blends with SF/CS blend ratios of 1:0, 2:1, 1:1, 1:2 and 0:1 (w/w) were prepared using the water-in-oil emulsification-diffusion method without any surfactants. An aqueous SF/CS blend solution and ethyl acetate were used as the water and oil phases, respectively. The plain SF had an irregular shape, while the CS microparticles were spherical. The blend microparticles were spherical in shape with a rough surface. Average microparticle sizes were in the range of 73-80 μm. The microparticle matrices had a sponge-like morphology. Conformational changes in the SF component, from random coil to the β-sheet form, were observed in the FTIR data. The dissolution of the blend microparticles was lower than those of the plain SF and CS microparticles. Microparticle density steadily increased and porosity slightly decreased as the amount of CS in the blend increased.

Preparation and Characterization of Keratin/Alginate Blend Microparticles

“…In the latter case, it may be caused because of the low amount of the Ker protein used, which was not enough to enclose particles. It would be expected that the hollow or porous microparticles occurred due to high amount of water diffused out from emulsion droplets to the external phase of ethyl acetate [16,17]. e Ker microparticles had higher uniformity in shapes when the concentration was increased to 0.8% w/v (Figure 1(b)).…”

Silk‐based microcarriers: current developments and future perspectives

“…Nevertheless, chitosan microparticles have limitations such as a high initial burst release rate and a short period of sustained‐release [88]. Several works focus on the synthesis of fibroin/chitosan to increase the release period, using a spray‐drying technique [62, 89] or an emulsification approach [90–92]. The microspheres obtained usually present a smooth [88, 90] or wrinkled surface [90–92] with a diameter that can range from ∼7 to 150 μm [90].…”

“…The dissolution of the microparticles can be controlled by adjusting the fibroin/chitosan blend ratio. According to the study of Cheerarot and Baimark [91], increasing the chitosan content in the blend led to a further decrease in the dissolution percentage. Adding different components is also a route to obtain different release periods.…”

Preparation of silk fibroin carriers for controlled release

“…Silk fibroin microparticles can be prepared using several methods, such as emulsion method (Cheerarot et al, 2015), self-assembly (Shi et al, 2011), and phase separation (Lammel et al, 2010). The microparticles can be coated with biological molecules to make them interact with a biological entity and provide a controlled release.…”

“…Microspheres are defined as the bioactive molecules dissolved or dispersed in the polymer matrix to form spherical particles, which possess the sustained release effect and are capable of targeting to specific tissues or organs. Silk fibroin microspheres can be fabricated using numerous methods such as emulsification diffusion (Cheerarot et al, ), silk/PVA blend films (Wang et al, ), spray‐drying (Tomoaki et al, ), and microfluidics (Breslauer et al, ). Currently, silk fibroin microspheres can be devised as some new controlled drug/gene delivery systems.…”