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arXiv · 1706.06327

Femtosecond laser induced surface modification for prevention of bacterial adhesion on 45S5 bioactive glass

Abstract

Bacterial attachment and biofilm formation on implant surface has been a major concern in hospital and industrial environment. Prevention of bacterial infections of implant surface through surface treatment could be a potential solution and hence this has become a key area of research. In the present study, the antibacterial and biocompatible properties of femtosecond laser surface treated 45S5 bioactive glass (BG) have been investigated. Adhesion and sustainability of both gram positive S. aureus and gram negative P.aeruginosa and E. coli nosocomial bacteria on untreated and laser treated BG samples has been explored. An imprint method has been used to visualize the growth of bacteria on the sample surface. We observed complete bacterial rejection potentially reducing risk of biofilm formation on laser treated surface. This was correlated with surface roughness, wettability and change in surface chemical composition of the samples before and after laser treatment. Biocompatibility of the laser treated BG was demonstrated by studying the anchoring and growth of human cervix cell line INT407. Our results demonstrate that, laser surface modification of BG enables enhanced bacterial rejection without affecting its biocompatibility towards growth of human cells on it. These results open a significantly potential approach towards use of laser in successfully imparting desirable characteristics to BG based bio-implants and devices.

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Shazia Shaikh, Deepti Singh, Mahesh Subramanian, Sunita Kedia, Anil Kumar Singh, Kulwant Singh, Nidhi Gupta, Sucharita Sinha. 2017-06-20. Femtosecond laser induced surface modification for prevention of bacterial adhesion on 45S5 bioactive glass. https://doi.org/10.1016/j.jnoncrysol.2017.12.019

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