Article

Biodegradability, antimicrobial activity and properties of PVA/PVP hydrogels prepared by γ-irradiation

Journal of Polymer Research (Impact Factor: 1.9). 01/2008; 16(1):1-10. DOI: 10.1007/s10965-008-9196-0

ABSTRACT Polyvinyl alcohol/polyvinyl pyrrolidone (PVA/PVP) hydrogel has been prepared by using γ-irradiation technique. In the present
study the conclusion on miscibility of PVA/PVP blends, confirmed qualitatively and quantitatively by using Fourier transform
infrared spectroscopy and differential scanning calorimetry, respectively. PVA and PVP are found to form a thermodynamically
miscible pair. The physical properties such as gel fraction and water absorption performance of the prepared hydrogels were
measured, it was found that the gel fraction increases with increasing irradiation dose while the swelling of PVA/PVP blended
hydrogels nearly tends to increase with increasing PVP content and reduced with enhanced irradiation doses. The hydrogel pore
structure of various PVA/PVP compositions were tested with SEM. Ability of PVA/PVP hydrogels to absorb and release antimicrobial
compounds was tested using amoxicillin as an antibacterial and ketoconazole as an antifungal. Antimicrobial activity of PVA/PVP
hydrogels was examined using four bacteria, and four fungi. No antibacterial or antifungal activities of non-loaded PVA/PVP
of various compositions were detected while the loading ones found to have antimicrobial activity. Results showed resistance
of Pseudomonas aeruginosa and Candida albicans to PVA/PVP, while Bacillus subtilis was very sensitive. Biodegradation of PVA/PVP hydrogels was investigated by burial method in two types of local soils (clay
and sandy soils). The highest degradation rate was found to be achieved using clay soil. Also, effect of irradiation dose
on its biodegradability was tested. The results showed that the radiation prepared PVA/PVP hydrogels can be use as biomaterials.

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