Phytochemically enriched male papaya flowers: a better green candidate for silver nanoparticle synthesis and exploring its antibacterial potency

Abstract

Innovating green pathways for fabricating metal nanoparticles (MNPs) turns into an essential subject to promote sustainability and protect our environment from toxicity. Carica papaya is one of the most common cultivations with enriched phytochemicals. Here in this work, we have used male Carica papaya extract (CPE) from its flowers to synthesize eco-friendly silver nanoparticles (AgNPs). The physicochemical properties of CPE-reduced AgNPs (CPE-AgNPs) were studied by different spectroscopic techniques. The characteristic property of AgNPs has been confirmed by analyzing the surface plasmon resonance (SPR) band of CPE- AgNPs: at around 440 nm. The capping of as-prepared AgNPs mediated by CPE was evaluated based on the vibrational bands of functional groups by Fourier Transform Infra-Red (FTIR) spectrometer. The elemental silver composition present in CPE-AgNPs was evidently seen from the corresponding Energy Dispersive X-ray spectroscopic (EDS) measurements. Studies obtained from Transmission Electron Microscopy (TEM) images of CPE-AgNPs reveals that the majority of the CPE-AgNPs are spheres of 11.10 ± 2.30 nm diameter. The Zeta potential value for CPE-AgNPs prepared using 2 ml of CPE was 65.0 ± 2.1 mV, which ensured better stability, and the sample was selected for further studies. CPE-AgNPs show better antibacterial efficacy against bacterial strains and suggest that they can be used for developing AgNPs based medical devices such as urinary catheters to treat urinary tract infections (UTIs).