Cross-Linked Biopolymer Stabilized Exfoliated Titanate Nanosheet-Supported AgNPs: A Green Sustainable Ternary Nanocomposite Hydrogel for Catalytic and Antimicrobial Activity

Abstract

For the first time, we report in situ exfoliated titanate nanosheet-supported silver nanoparticles (AgNPs) toward environmental sustainability through rapid catalytic reduction of p-nitrophenol (4-NP), organic dyes for decoloration, as well as by inhibiting the growth of microbes. The ternary nanocomposite hydrogel has been synthesized through stabilization of an anionically charged titanate sheet by threedimensional amino-functionalized chemically cross-linked amylopectin for proper growth and stabilization of AgNPs. Here, titanate nanosheets act as an excellent solid support for proper fabrication of AgNPs that could restrict its agglomeration and rapid leaching of AgNPs from the ternary nanocomposite hydrogel. The structural confirmation as well as the stability of titanate nanosheets along with AgNPs have been studied using various characterization techniques. The preparaed nanocomposite hydrogel demonstrates excellent catalytic efficacy and recycling ability toward rapid reduction of toxic 4-NP and decoloration of organic dyes. Notably, the complete reduction of 4-NP could be accomplished within 16 s using 5 mg of as synthesized cl-AP/exf.LT-AgNPs in the presence of excess NaBH 4 . The excellent catalytic efficiency of the ternary nanocomposite hydrogel arises from the synergistic effects of cross-linked amylopectin stabilized titanate nanosheets and in situ fabrication of AgNPs. Moreover, the strong bactericidal activity (3.2 mg/mL for 10 7 cells/mL of Escherichia coli and Bacillus subtilis) of the ternary nanocomposite hydrogel would overcome the limitations for removal of water-soluble organic pollutants and microbial contaminants owing to future perspective on environmental sustainability.

In Situ Synthesis of a Silver-Containing Superabsorbent Polymer via a Greener Method Based on Carboxymethyl Celluloses

“…It can also be seen that with increasing AgNO 3 , the antibacterial effect improves because the silver content increased, thus enhancing the antibacterial effect. Some other studies also proved that silver nanoparticles used in biomass composites exhibit good antibacterial activity [ 57 , 58 ].…”

Bimetallic Nanoparticles Anchored on Core–Shell Support as an Easily Recoverable and Reusable Catalytic System for Efficient Nitroarene Reduction

“…Though p -nitrophenol reduction is thermodynamically favorable in the presence of NaBH 4 , its kinetic barrier prompts investigations on metal-based catalysts, such as Ag NPs for facile and rapid reduction. 34 Consequently, in the present study, we have employed Fe 3 O 4 @CS_AgNi as a heterogeneous catalyst for the p -nitrophenol reduction. As p -nitrophenolate and p -aminophenolate anions show their distinctive absorption peaks at 400 and 300 nm, respectively, in their UV–visible spectrum, electronic spectroscopy was employed to investigate the reduction process as a function of time.…”

Antimicrobial Hydrogels: Promising Soft Biomaterials

“…Due to its hydrophilic nature and incorporated antimicrobial activity starch hydrogel is extensively used in biomedical applications such as drug delivery, coating, wound dressing, implantable devices, and biosensors. [8] In 2012 Bihua Xia et al prepared a hybrid tapioca starch chitosan-based hydrogel that contains Ag nanoparticles. They first prepared a dialdehyde starch in presence of sodium periodate.…”