Silica from waste rice husk and its polymeric hydrogel-based composite filler: synthesis, characterisation, and antibacterial activity

ABSTRACT

Researchers are focusing on the development of bio-fillers through different approaches for dental purposes. The present work reports a relatively simple and faster chemical approach for synthesising composites using silica from waste rice husk along with PEGMA, PNIPAm, HEMA, APS, and MBA. The synthesis includes no harmful chemical reagents and focuses on the effective management of waste. The X-ray diffraction revealed the crystalline nature of composite and with an average crystallite size of 35 nm for the silica particles. The average particle size for silica was found in the range 200–230 nm from dynamic light scattering having a stable structure with −18.23 ± 0.5 mV as the zeta potential. The porosity was analysed using scanning electron microscopy and the stoichiometric composition by energy-dispersive spectroscopy with the pore size from 95–350 nm. Fourier transform infrared spectroscopy revealed the presence of different functional groups. The thermal stability of silica was analysed through Thermogravimetric analysis. The antibacterial activity of the composite against E.coli and S. aureus demonstrated its efficacy against bacterial growth inhibition. The porous composite can be effectively used as a filler material in potential biomedical applications including dental composite for sustained drug loading and release.

KEYWORDS:

• Agricultural waste
• characterization
• dental composite
• hydrogel
• silica

Acknowledgements

The authors thank the Indian Institute of Information Technology, Allahabad, and Babasaheb Bhimrao Ambedkar University, Lucknow, and Scientium Analyze Solutions, Jaipur for providing the material characterization facilities.

Disclosure statement

No potential conflict of interest was reported by the authors.