On the optical and thermal properties of in situ/ex situ reduced Ag NP’s/PVA composites and its role as a simple SPR-based protein sensor

Abstract

Silver/polyvinyl alcohol (Ag-PVA) nanocomposite films have been prepared via in situ generation of silver nanoparticles (Ag NPs) by the respective metallic salts and dispersion of preformed Ag NPs (ex situ synthesis) inside polyvinyl alcohol (PVA) and its effect of sensing towards a model protein (bovine serum albumin-BSA) was investigated. The influence of Ag NPs, irrespective of their reduction methodology on the optical and the thermal properties of the PVA, had been investigated using UV-Vis spectrophotometer and differential scanning calorimetry. The absorption peak around 400 nm indicates the surface plasmon resonance response of Ag NPs. The interaction of the dispersed and preformed Ag NPs with the PVA chains is confirmed by the corresponding vibrational signatures of the PVA through Fourier transform infrared spectroscopy (FTIR). The changes in the glass transition and melting temperatures (T g and T m ) of the pure PVA upon the presence of Ag NPs are reported using differential scanning calorimeter (DSC). The sizes of the synthesized Ag NPs are found to be in the range of 200 ± 10 nm for in situ reduction of silver nitrate (AgNO 3 ) and 100 ± 10 nm for the external addition of preformed Ag NPs by sodium borohydride (NaBH 4 ) reduction using scanning electron microscopy (SEM).

Novel, silver-ion-releasing nanofibrous scaffolds exhibit excellent antibacterial efficacy without the use of silver nanoparticles

“…Silver in the form of nanoparticles has been incorporated in nanofibers by either in situ generation of nanoparticles within the polymer (18–20) or dispersion of prepared nanoparticles in the system ( ex situ synthesis) (21,22). However, the very small size of nanoparticles allows them to penetrate into the stratum corneum of skin (23,24) or diffuse within the cellular plasma membrane and interfere with a variety of cellular mechanisms (22,25).…”

Characterization of a silica-PVA hybrid for high density and stable silver dissolution

“…This peak grew significantly both over time and after heating the film to 100 o C. The color of the films ranged from pale yellow (PVA) to deep amber (PVA-100 o C and PVA-A). These results illustrate that the PVA host is intrinsically reducing the silver ions to metal [2].…”

“…A key example of this is the production of embedded metal nanoparticles, where the host material is responsible for the reduction of the metal ions to atoms, and stabilization of the resulting nanoparticles. The surface plasmon resonance (SPR) of these encapsulated nanoparticles has been exploited for micro-polarizers [1], optical sensors [2], and 3D optical storage units [3]. Materials with embedded metal nanoparticles can also exhibit antimicrobial properties [4,5].…”

A Review On The Diverse Application Of Silver Nanoparticle

“…The plasmonic and photonic characteristics of silver nanoparticle and the silver nanoparticle loaded compound, such as silver loaded poly vinyl alcohol (Ag-PVA) (Figure 1) are used for light guiding and optical sensing applications [15,16]. Silver nanoparticle are useful in semiconductor applications due to its rapid trapping of free electrons.…”