Fabrication and characterisation of a wound dressing composed of polyvinyl alcohol and quince seed mucilage.

OBJECTIVE: Providing a suitable environment to improve the healing process is the main target of wound dressing that also protects the wound from additional harms. In the present study, fabrication and characterisation of a new kind of electrospun wound dressing composed of polyvinyl alcohol (PVA) and quince seed mucilage (QSM) is reported. METHOD: QSM was extracted from quince seeds, purified, freeze-dried and used to produce aqueous solutions containing different amounts of PVA and QSM. The wound dressings were fabricated via the electrospinning method and their characteristics were investigated with scanning electron microscope (SEM) images, Fourier transform infrared (FTIR) spectra, tensile and swelling test, and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) cytotoxicity assay against fibroblast cells. RESULTS: SEM images confirmed that proper, uniform, non-oriented nanofibres with an average diameter in the range of 60-240nm, depending on the QSM content had been fabricated. The tensile test showed that with increasing QSM content, the tensile strength of fibre increased while elongation at break was decreased, which was consistent with SEM images where the diameter of samples decreased by increasing QSM content. MTT assay showed significant biocompatibility against fibroblast cells; however, it was increased by increased QSM proportion. In addition, SEM images supported the proper adhesion of fibroblast cells on the sample one day after culturing. CONCLUSION: Overall, the findings of the current study support the potential of PVA/QSM nanofibres as a proper candidate for biomedical applications, especially as a wound dressing.

Effective factors in the treatment of kerosene-water emulsion by using UF membranes.

The effects of different parameters including membrane type (regenerated cellulose and polysulphone), transmembrane pressure (TMP), the content of oil in the feed, the flow velocity of the feed and pH on the ultrafiltration of an emulsion of kerosene in water were studied. It was found that the important factors affecting ultrafiltration were, in order, membrane type, pressure and oil concentration. The greatest flux at the optimum conditions here of 3 bar, an oil content of 3% (v/v) and with membrane type C30F was predicted as 108 L/(m(2)h) that was within the range of the confidence limit of the measured value of 106 L/(m(2)h). The normalised FTIR results of the virgin cellulosic membranes C30F and C100F showed more abundant OH groups. The bigger number of OH groups implies a greater hydrophilicity. The larger observed flux in the C30F is related to a higher number of pores as well (surface porosity) compared with the C100F membrane. In the "polarised regime" from 3 bar upwards, flux was independent of pressure for all membranes and was assumed to be determined by the back diffusion transport. Despite the fact that both the PS100H and C100F membranes had the same cut-off (100 kg/mol), the hydrophilic C100F showed a superior permeate flux. The strongest drop of flux with time due to oil fouling was observed for the C100F although it was hydrophilic. In the case of the PS100H, both FTIR and SEM showed that cake layer formation was not the cause of fouling. Meanwhile the SEM and FTIR results of fouled C100F provided evidence of adsorptive and gel formation fouling.