Biogenic Silver Nanoparticles/Mg-Al Layered Double Hydroxides with Peroxidase-like Activity for Mercury Detection and Antibacterial Activity

Abstract

Over the past decade, the attention of researchers has been drawn to materials with enzyme-like properties to substitute natural enzymes. The ability of nanomaterials to mimic enzymes makes them excellent enzyme mimics; nevertheless, there is a wide berth for improving their activity and providing a platform to heighten their potential. Herein, we report a green and facile route for Tectona grandis leaves extract-assisted synthesis of silver nanoparticles (Ag NPs) decorated on Mg-Al layered double hydroxides (Mg-Al-OH@TGLE-AgNPs) as a nanocatalyst. The Mg-Al-OH@TGLE-AgNPs nanocatalyst was well characterized, and the average crystallite size of the Ag NPs was found to be 7.92 nm. The peroxidase-like activity in the oxidation of o-phenylenediamine in the presence of H2O2 was found to be an intrinsic property of the Mg-Al-OH@TGLE-AgNPs nanocatalyst. In addition, the use of the Mg-Al-OH@TGLE-AgNPs nanocatalyst was extended towards the quantification of Hg2+ ions which showed a wide linearity in the concentration range of 80–400 μM with a limit of detection of 0.2 nM. Additionally, the synergistic medicinal property of Ag NPs and the phytochemicals present in the Tectona grandis leaves extract demonstrated notable antibacterial activity for the Mg-Al-OH@TGLE-AgNPs nanocatalyst against Gram-negative Escherichia coli and Gram-positive Bacillus cereus.

Assessment of Some Characteristics of a Novel Photocatalyst Based on Hydrotalcite Mg‐Al‐Ag, Titanium Dioxide and Magnetic Iron Nanoparticles

“…Presently observe, the FNPs can withstand both types of bacteria with an inhibition zone of 10 mm after 24 hours of growth at 37 °C. This demonstrates that FNPs can enhance the antimicrobial activity of FSHT samples [55,57] . The FSHT samples also against the above two species of bacteria with high value of inhibition zone.…”

“…The FSHT samples also against the above two species of bacteria with high value of inhibition zone. Along with recovery enhancement, the inclusion of FNPs improved antibacterial properties of the FSHT samples [57] . As a result, the FSHT particles aspired to have strong antibacterial and self‐cleaning membrane capabilities when exposed to sunshine.…”

Palladium Nanoparticles Grafted onto Phytochemical Functionalized Biochar: A Sustainable Nanozyme for Colorimetric Sensing of Glucose and Glutathione

“…To determine the effect of reaction parameters such as variation in pH of acetate buffer, catalyst loading, and concentrations of H 2 O 2 and OPD on the peroxidase-like activity of the BC-AHE@Pd nanocatalyst, the oxidation was carried out under varying reaction conditions. The peroxidase-like activity is related to the pH according to the pH-dependent studies, as well as the concentrations of substrates and nanocatalysts [ 48 , 49 ]. The superlative activity of the BC-AHE@Pd nanocatalyst was obtained at pH 4 ( Figure 8 a), with OPD (100 μM) and H 2 O 2 (40 mM) in the presence of 0.31 mol% Pd of the BC-AHE@Pd nanocatalyst.…”

Bio‐Synthesis of Silver Nanoparticles Decorated on Hydrotalcite using Psidium Guajava Leaf Extract and Its Anti‐Bacterial Effect

“…The appearance of these extract peaks in the IR spectra leads to suggestion that organic substances also contribute to the modification of the HT surface in the HT-AgNPs samples, and they potentially act as a stabilization agent for AgNPs. [41] This highlights the distinction between the use of a chemical reducing agent and a plant extract reducing agent. Ballarin et al reported that the FTIR spectra of ZnAl-AgNPs were similar to that of raw ZnAl HT when using glucose or sodium citrate as reducing agents to convert Ag(I) to AgNPs.…”

“…They were applied as sensors for mercury detection. [41] From the above literature, it can be seen that Psidium guajava leaf extract is an efficient reducing agent for converting Ag(I) ions to AgNPs. However, the study on the 'green' synthesis of AgNPs on HT particles using Psidium guajava leaf extract as a reducing agent has still been limited.…”