The cytotoxicity and anti-influenza virus (IFV) activity of calcium or zinc alginate fibers were investigated to explore the feasibility of them to be used as biomaterials. African Green Monkey kidney cell (Vero) and human cervical cancer cell (Hela) cultured with alginate fibres were used to screen cytotoxic effects. After 48 h, MTT (3-(4,5-dimethyl-2-thiazol)-2,5-diphenyl-2H tetrazolium bromide) assays were performed. Then cytotoxicity was evaluated with six grades according to cell relative growth rate (RGR). In anti-IFV activity assay, IFV were added to all fibers and the Vero cell survival were detected by MTT assays with calculating the percentage of protection. The cytotoxity of calcium alginate fibers on Vero were grade 0 or 1 in contrast to zinc alginate fibers which was grade 0. The cytotoxity of calcium or zinc alginate fibers on Hela were grade 0. Furthermore, partial calcium or zinc alginate fibers could promote Vero or Hela cell growth. In antiviral assay the highest percentage of protection of calcium alginate fibers was 34.42%, while that of zinc alginate fibers was 59.42%. The results showed that calcium or zinc alginate fibers had a good cellular biocompatibility and the large weight zinc alginate fibers had a better anti-IFV activity than calcium alginate fibers, which is potential for tissue engineering.

Abstract Sodium alginate was provided with good processibility according to physical and chemical characterization of itself. Alginate scaffold has been used for preparation of soft or hard tissue engineering, but the structure of the scaffold needs to be improved for better performance for skin tissue engineering. In this study, highly porous alginate membrane was formed with ionic crosslinking. High molecular weight (Mw=3.0×105) alginate showed the best film-forming property. Therefore, the appropriate molecular weight should be selected for improving its performance. With freeze-drying technology and pre-freezing at -10°C, we have built the honeycomb materials (porosity=92.06%). Changing the pre-freezing temperature can regulate pore structure to some extent. With the increased dosage of sodium alginate, the porosity and the pore size of the materials were reduced, whereas tensile strength and elongation at break increased. Water absorption performance of the materials was good. The above studies lay a foundation for construction of skin tissue engineering scaffold.

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As a natural polymer, alginic acid is widely used in medical fields for its biodegradability, low toxicity and immunogenicity. In this paper, four kinds of cavernous calcium alginate wound dressings were prepared, and physical properties were tested, providing fundamental basis for further study. The results indicate that glycerin is not suitable as a plasticizer for this cavernous wound dressing; a relatively uniform structure of the calcium alginate wound dressing would be obtained as the solution temperature increased; the mechanical properties decrease with the increase of the pre-freezing time.

To apply copper alginate fibers in medical as a new alginate fiber, copper alginate fibers were researched and evaluated against Escherichia coli (E.coli) and Staphylococcus aureus (S.aureus), using antibacterial zone and flash shaking method to analyze anti-bacterial mechanism by the scanning electron microscopy (SEM). The results showed that copper alginate fibers had antibacterial effects, the antibacterial rate against E.coli and S.aureus were 97.4% and 66.2%, respectively; SEM images indicated that bacteria obviously changed after contacting with fibers, the main reason was that copper ion had a damaging effect on pericellular and cell wall. Furthermore, bacterial osmotic pressure was changed and protein synthesis were impeded, and then the normal metabolism of bacteria was destroyed, and finally, bacteria died.