Hispidin hybridized strontium oxide: a nanobiohybrid system for opto-electrochemical functionality

Abstract

Strontium oxide (SrO) and polyphenol-based research on bone health, tissue engineering, anti-oxidant and anti-inflammatory are available in literature, yet the opto-electrochemical characteristics of SrO incorporated with polyphenol-derived from fungus (mushroom metabolite, Hispidin) remains unexplored. Here, we report the solvothermal-mediated synthesis of SrO nanoparticles and its surface modification with Hispidin (His) via PEGylation using ultrasonochemical process. As synthesized SrO-PEG/His exhibit absorption bands at 290 and 369 nm ascribed to π-π* and n-π* transitions, respectively. Photoluminescence study of SrO-hybridized Hispidin shows a visible light emission band centered at 427 nm, enabling a blue shift from the pristine Hispidin. FT-IR spectral analysis confirmed the occurrence of interaction between CO functional group of Hispidin and PEGylated SrO. Electron and atomic force micrograph suggest the formation of nanoscale particles with an average particle size distribution of 50 nm and roughness factor of 0.89 nm, respectively. Electron paramagnetic resonance spectral analysis affirmed that SrO-PEG/His exerts a dosage dependent (0.1 to 1 mg/mL) radical scavenging activity against standard free radical. Preliminary electrochemical studies, from cyclic voltammetry, on SrO-PEG/His modified glassy carbon electrode suggest the quasi-reversible redox behavior, following 2e⁻/2H⁺ transfer at the electrode-electrolyte interface. Observed results ensured that the opto-electrochemical characteristics of the synthesized nanobiohybrid system are useful for antioxidant and sensor probe construction, paving the way for futuristic applications in theranostics.