Green Synthesis of Flower-Like Carrageenan-Silver Nanoparticles and Elucidation of Its Physicochemical and Antibacterial Properties

Abstract

Herein, we report the green synthesis of flower-like carrageenan-silver nanoparticles (c-AgNPs) through a facile hydrothermal reaction at 90 °C for 2 h. The reduction of silver nitrate (AgNO3) to c-AgNPs was evident by the colour change of the solution from colourless to dark brown and further confirmed by a UV-Vis surface plasmon resonance (SPR) peak at ~420 nm. The FTIR spectra showed that the abundance of functional groups present in the carrageenan were responsible for the reduction and stabilisation of the c-AgNPs. The XRD pattern confirmed the crystalline nature and face-centred cubic structure of the c-AgNPs, while the EDX analysis showed the presence of a high composition of elemental silver (85.87 wt%). Interestingly, the morphological characterisations by SEM and FE-SEM revealed the formation of flower-like c-AgNPs composed of intercrossed and random lamellar petals of approximately 50 nm in thickness. The growth mechanism of flower-like c-AgNPs were elucidated based on the TEM and AFM analyses. The c-AgNPs displayed promising antibacterial properties against E. coli and S. aureus, with zones of inhibition ranging from 8.0 ± 0.0 to 11.7 ± 0.6 mm and 7.3 ± 0.6 to 9.7 ± 0.6 mm, respectively, as the concentration of c-AgNPs increased from 0.1 to 4 mg/mL.

Electron Beam-Supported Fabrication of Biocompatible Silver/iota-Carrageenan for Wound Healing Application

“…Furthermore, water-soluble radicals contribute to additional Ag(I) reduction by producing free radicals in ι-carrageenan following the release of H • radical from the macromolecule’s structure (eq ). In addition to serving as a nucleating agent, the ι-carrageenan matrix may encapsulate the cations of Ag(I), resulting in the creation of metallic ι-carra@AgNPs. , Ag normalN O 3 → water Ag + + normalN O 3 − H 2 normalO → E‐beam e − aq + H • + OH • + H 2 O 2 • + OH − + H + Ag + + e − aq → Ag false( 0 false) Ag + + H • → Ag false( 0 false) + H + Ag false( 0 false) + Ag + → Ag 2 2 + • Ag 2 2 + • + …”

“…Due to the rise and spread of bacteria species resistant to a wide range of antibiotics, many scientists are focusing their efforts on discovering novel antimicrobial reagents that are effective. AgNPs may have a wider spectrum of action and lower likelihood of microbial resistance when compared to antibiotics …”

“…AgNPs may have a wider spectrum of action and lower likelihood of microbial resistance when compared to antibiotics. 8 The simplest and most popular technique for producing AgNPs involves the chemical reduction of ions of silver in solution. However, it is significantly more difficult and timeconsuming to remove the dangerous and destructive reducing and stabilizing agents, including hydrazine hydrate, sodium borohydride, N,N-dimethylformamide, elemental hydrogen, and surfactants, employed in the chemical reduction method.…”

Green synthesis of silver nanoparticles and its environmental sensor ability to some heavy metals

“…Figure 14 c displays the energy dispersive X-ray (EDX) spectrum, employed to assess the purity and composition of the green-synthesized AgNPs. The presence of AgNPs is confirmed by the prominent Ag peak in the EDX spectra at 3 keV [ 112 ]. Elemental analysis revealed a high silver content in the sample (73.86 wt%).…”

Biosynthesis and Characterization of Silver Nanoparticles Using Tribulus terrestris Seeds: Revealed Promising Antidiabetic Potentials

“…Plasmonic nanoparticles, including gold, silver, and platinum particles, are discrete metallic particles that have unique optical properties due to their size and shape and are increasingly being incorporated into commercial products and technologies. These technologies, which span fields ranging from photovoltaics to biological and chemical sensors, take advantage of the extraordinary efficiency of plasmonic nanoparticles at absorbing and scattering light [ 30 , 31 ].…”