A new cellular model for in vitro biocompatibility evaluation of microcapsule materials

Fibrosis caused by the host response to long-term transplanted microcapsules and the limitation of traditional L929 cell model for biocompatibility testing inspire the development of an assay of biocompatibility based on macrophage behavior. In this paper, the human monocytic cell line THP-1 was utilized for biocompatibility evaluation of microcapsule materials. The cell viability and secretion of nitric oxide (NO) and cytokines served as index of biocompatibility were assayed. It was found that the evaluated microcapsule materials had no effect on the stimulation of NO and cytokines secretion, which meant that these materials were biocompatible. Furthermore, it suggests the THP-1 cell a convenient in vitro experimental model that might be useful for long-term predictions of material biocompatibility.

Morphology transcription process from CMC micelles to inorganogel and its effect on the properties of alumina particle

In this study, a carboxymethyl cellulose (CMC)-mediated sol-gel process was developed to synthesize the alumina hydoxide whiskers. During the process, inexpensive inorganic salts were used as precursors and supercritical drying method was used to extract the water in hydrogel. The influences of CMC on the gel formation and the particle morphology were investigated. The results show that the formation of CMC-aluminium hydroxide organic-inorganic hybridgels led to a morphology transcription process from CMC micelles to aluminium hydroxide gel, as a result, the precursor with whiskerious morphology was obtained.

Insight into permeability of protein through microcapsule membranes

The objective of this paper is to analyze the characteristics of protein permeability in alainate-polylysine-alginate (APA) and alginate-chitosan-alginate (ACA) microcapsules by mathematical models based on the balance of chemical potential. The comparison between calculated results and experimental data shows that the models can describe the process of protein diffusion from microcapsule and protein release into microcapsule successfully. The influences of membrane composition on the permeability of ACA microcapsule have been investigated and analyzed. The effect of resistance on the mass transfer is further analyzed theoretically with the aid of mathematical modeling. (c) 2005 Elsevier B.V. All rights reserved.