Sustainable hydroxypropyl methylcellulose/xyloglucan/gentamicin films with antimicrobial properties

July 28, 2017

Title

Sustainable hydroxypropyl methylcellulose/xyloglucan/gentamicin films with antimicrobial properties

Author

Stalin Kondaveeti, Tatiana C. Damato, Ana M. Carmona-Ribeiro, Maria R. Sierakowski, Denise Freitas Siqueira Petri

Year

2017

Journal

Carbohydrate Polymers

Abstract

Hydroxypropyl methylcellulose (HPMC) and xyloglucan (XG) crosslinked with citric acid over a range of HPMC/XG weight ratios formed sustainable blend films characterized by Fourier transform infrared spectroscopy, thermogravimetric analysis, scanning electron microscopy, tensile tests, circular dichroism and determination of inhibitory activity against Staphylococcus aureus and Escherichia coli. Both in solution and in the crosslinked films, HPMC chains lost the original ordered conformation upon interacting with XG, giving rise to an entropic gain. The highest values of tensile strength (25 MPa) and Young’s modulus (689 MPa) occurred for the 50:50 HPMC/XG blend films. In vitro loading of gentamicin sulfate (GS) in the films amounted to 0.18 ± 0.05 −0.37 ± 0.05 g of GS per g polymer. At pH 7.4 and 37 °C, the GS release kinetics from the films fitted with the Korsmeyer–Peppas model revealed a non-Fickian release mechanism with diffusional coefficient n ∼ 0.7. The cross-linked films of HPMC, XG and their blends loaded with GS showed outstanding antibacterial activity against Staphylococcus aureus and Escherichia coli, disclosing their potential for novel biomedical applications.

Instrument

J-720

Keywords

Circular dichroism, Secondary structure, Polymers