Preparation of Hybrid Hydrogel Containing Ag Nanoparticles by a Green in Situ Reduction Method

Abstract

In this Article, large and uniform Ag nanoparticle-containing hybrid hydrogels were prepared by in situ reduction of Ag ions in cross-linked tapioca dialdehyde starch (DAS)–chitosan hydrogels. In the hybrid hydrogels, chitosan was chosen as a macromolecular cross-linker because of its abundant source and good biocompatibility. The hybrid hydrogel showed good water-swelling properties, which could be controlled by varying the ratio of chitosan to tapioca DAS in the hydrogel. The reductive aldehyde groups in the cross-linked hydrogels could be used to reduce Ag ions to Ag nanoparticles without any additional chemical reductants. Interestingly, by controlling the reduction conditions such as the tapioca DAS concentration, aqueous AgNO3 concentration, reaction time, and aqueous ammonium concentration, Ag nanoparticles with different sizes and morphologies were obtained. Because of their biocompatibility, degradable constituents, mild reaction conditions, and controlled preparation of Ag nanoparticles, these tapioca DAS–chitosan/Ag nanoparticle hybrid hydrogels show promise as functional hydrogels.

Self-Assembled Nanocomposite Film with Tunable Enhanced Fluorescence for the Detection of DNA

“…Silver ions were adsorbed on the top anionic ALG layer, and then reduced in-situ by the aldehyde groups of the ALG (which acted as a reducing agent), forming an Ag-PE film. 51 A thin layer of cationic PEI was then deposited, to improve the self-assembly ability of the structure. Anionic polyelectrolyte PAA and cationic polyelectrolyte CS were deposited stepwise via self-assembly, to form an interlayer.…”

Polysaccharide-based nanocomposites and their applications

“…The aldehyde groups in tapioca dialdehyde starch make it possible to prepare a cross-linked hydrogel with amino-containing chitosan by the Schiff base reaction. The aldehyde groups reduce and stabilize the Ag NPs [70]. …”

“…Large and uniform Ag NP-containing hybrid hydrogels have been prepared by in situ reduction of Ag + in cross-linked tapioca dialdehyde starch–chitosan hydrogels. By controlling the reduction conditions, such as polysaccharide concentration, aqueous AgNO 3 concentration, reaction time, and aqueous ammonium concentration, Ag NPs of different sizes and morphologies could be obtained [70]. These hydrogels showed good swelling behavior in water, and demonstrated high biocompatibility.…”

Organic/inorganic nanocomposite hydrogels

“…These polymers contain poly(3,4-ethylenedioxythiophene) (Xiao et al, 2013), poly(ethylene oxide propylphosphonamidate) (Zhang et al, 2013), dextran (Ma et al, 2009), dialdehyde starch (Xia et al, 2012), and so on. These polymers contain poly(3,4-ethylenedioxythiophene) (Xiao et al, 2013), poly(ethylene oxide propylphosphonamidate) (Zhang et al, 2013), dextran (Ma et al, 2009), dialdehyde starch (Xia et al, 2012), and so on.…”