Papers by Author: Chen Hui Zhu

Abstract: In this paper, the cross-linking injection hydrogel were synthesized by EDC crosslinker and Carboxymethyl chitosan (CMCS)/Human-like collagen (HLC). Cytotoxicity was assessed by Methylthiazolydiphenyl-tetrazolium bromide (MTT) assay which indicated that the hydrogels was non-toxic to the BHK21 cell .Chondrocyct-encapsulation of this hydrogel were studied in order to asses the cells compatibility of the injection gel. The result showed that the material has no cytotoxicity to the cells and promoted cell adhesion and proliferation. Injected those hydrogels into mice subcutaneous , the following parameters were evaluated: inflammatory response, vascularization, new hypoderm generation. After 2,4,12,and 24 weeks of healing, the rats were sacrilifced suggested that gels in animals did not induce inflammation obvious, vessel bestrid the material after 4 weeks injection, new hypoderm generated in 12 weeks and packaged the hydrogels after 24 weeks. Consequently the gels are promised for the application in the biomaterials area.

Abstract: In this paper, the cross-linking hydrogels were synthesized by EDC crosslinker and Carboxymethyl chitosan (CMCS)/Human-like collagen (HLC). The morphology of the hydrogels was observed by scanning electron microscope (SEM). The important performance of these hydrogels is biodegradation which was assessed in two ways: (1) Through enzyme solution experiment in vitro , investigating in vitro degradation property. (2) Injecting the hydrogels to mice subcutaneous , after 2,4,12,and 24 weeks of healing ,the rats were sacrificed and explanted specimens were prepared for histology analysis. Investigating degradation time in vitro and in vivo , and studying the histology .HLC hydrogels degradation time gets eight to ten months, in addition has good compatibility of the histological performances. The hydrogels are promised for the applications in the biomaterials area.

Abstract: Hydrogels were prepared from carboxymethyl chitosan (CMCS)/Human-like collagen(HLC) by S-acetylmercaptosuccinic anhydride(SAMSA) crosslinker. Fourier transform infrared (FTIR) spectroscopy indicated that there exactly existed interaction HLC, carboxymethyl chitosan and SAMSA. The morphology of the hydrogels was observed by scanning electron microscope (SEM). The equilibrium swelling ratio was also evaluated. Cell culture results showed that these hydrogels were good in promoting the cell attachment and proliferation. The hydrogels are promised for the applications in the biomaterials area.

Abstract: Protected mercaptan groups may be introduced into Human-like collagen (HLC) under very mild conditions with S-acetylmercaptosuccinic anhydride(S-AMSA) as reagent. Fluorometric assay, Fluorescence Spectra and SDS-PAGE were employed to investigate the interaction between HLC and S-AMSA. These results obtained from this study provide theoretical evidence for the further investigate.

Abstract: A new hydrophobic method of regenerated silk fibroin was introduced here, in which glycerol was used as the inducer. As a consequence, the soluble form of silk was transformed into hydrophobic form, which hence suggests glycerol has a significant effect of hydrophobic induction. Then the morphology and mechanical properties of the hydrophobic silk fibroin was respectively shown by scanning electron microscope (SEM) and strain test. The results showed induced silk fibroin had a compact surface and good mechanical property. Finally, the induction mechanism of glycerol was discussed that glycerol could soften the fibroin’s structure during dry process ,which was the main reason leading to β-sheets of fibroin partly being rebuilt and then the hydrophobic transformation being achieved.

Abstract: High pressure electrostatic (HPE) was applied to prepare microcapsules, and the operation parameters of HPE were investigated in this paper. When ecletrocity voltage is 20 kV and the distance between two electrodes is 5 cm, the diameter of micro-beads can be around 500 μm that is the optimal diameter for dispersing in water. The release rate of BSA was coming up to 45% after 120 min in AGF and even to 89% after 240 min in AIF at 37°C to basically meet the release in full. The amount of bacteria in 2% (w/v) Na-alginate microparticles declined to 4.08 log cfu per ml which is 4 times more than that of free bifidobacteria after 120 min in AGF with incubation time by 5 log cycles.