Interaction of Ionic Liquid with Silver Nanoparticles: Potential Application in Induced Structural Changes of Globular Proteins

Abstract

Silver nanoparticles (AgNPs) show immense application potential in many fields including biomedical sciences owing to their advanced antimicrobial property (antibacterial, antifungal and anti-inflammatory). Ionic liquids (ILs) known as designer solvents with a melting point below 100 °C are a new class of compounds with exclusive properties and great chemical variety. Since the past decade, ILs are vastly used in interdisciplinary research including the synthesis and stabilization of metal nanoparticles. In the present work, we have studied the interaction between IL 1-butyl-3-methylimidazolium octylsulfate [Bmim]­[OS] and AgNPs using a simple and sensitive UV–visible spectroscopic method via the response obtained from the surface plasmon resonance (SPR) band of AgNPs. The analysis of the SPR band at the 400–425 nm range and the Fourier transform infrared (FT-IR) spectral results show a transfer of N–H stretching frequency from 3367 to 3228 cm–1, which clearly suggests the formation of nanoparticles. FT-IR spectroscopy is systematically applied to explore information about the intermolecular interactions taking place within AgNPs-[Bmim]­[OS] micellar solutions. The critical micelle concentration (CMC) of [Bmim]­[OS] is determined using conductivity and UV–visible spectroscopy, and the size of micellar aggregates is obtained using dynamic light scattering (DLS) technique. Further, the above system is also utilized to consider the structural modify of human serum albumin (HSA) and bovine serum albumin (BSA). UV–vis, fluorescence, FT-IR, 1H nuclear magnetic resonance and DLS spectroscopic investigations reveal some interesting outcomes. It is observed that modification in the structures of both the globular proteins HSA and BSA takes place within the system, thus indicating significant IL–protein binding. Further, it is noticed that HSA shows more binding affinity toward [Bmim]­[OS] than compared to BSA.

Microwave assisted green synthesis of silver nanoparticles for optical, catalytic, biological and electrochemical applications

“…With the addition of Cyanthillium cinereum leaf extract to the AgNO 3 solution, a steady change in colour from colourless to dark brown was observed, which was further confirmed by UV-vis spectroscopy [48]. The intensity of extremely symmetric single-band absorption with peak maxima of surface plasmon resonance (SPR) peaks for AgNP [49] synthesized at different concentration of AgNO 3 solution was analysed (Figure 1(a)) and found that a concentration of about 1 Â 10 À3 M AgNO 3 was adequate for the synthesis of AgNP [50]. Also, the absorption spectrum using the precursor 1 Â 10 À3 M AgNO 3 was verified at different intervals of time such as 180 s, 240 s, 300 s and 360 s [51] (Figure 1(b)) and observed that at a maximum of 360 s is enough for the complete formation of AgNP where there is a broad absorption peak at 418 nm and after a specific irradiation interval of 360 s coagulation of AgNP makes it difficult to analyse it by spectral data.…”

Unprecedented enhancement and preservation of the peroxidase activity of cytochrome-c packaged with ionic liquid-modified gold nanoparticles by offsetting temperature and time stresses

“…Furthermore, researchers have been trying to use the IL as a co-solvent during NP preparation to envisage the biocompatibility boosting capacity of IL-modified/functionalized NPs for the application of enzyme immobilization and protein stability. [13][14][15][16][17][18][19][20][21][22][23][24] First, for electrochemical catalysis applications, Liu et al 13 has introduced higher thermal stability and electrochemical catalytic ability of laccase in IL-carbon nanotube nanocompositemodified graphite electrodes. Similarly, Qian et al 17 has used ILs for the preparation of highly biocompatible laccase-based biocathodes.…”

“…Sequentially, Suo et al 20 have immobilized porcine pancreatic lipase onto functionalized IL-modified iron oxide (Fe 3 O 4 )–chitosan nanocomposites to enhance its catalytic performance. In 2019, Banjare et al 21 used IL-modified silver nanoparticles (AgNPs) to investigate the structural changes in the globular proteins. A greener approach for the synthesis of metal nanoparticles (MNPs) has been summarized by Mishra et al 25 in their recent review underlining the role of ILs in the preparation of noble metal NPs.…”

Thermodynamic and Kinetic Binding Behaviors of Human Serum Albumin to Silver Nanoparticles

“…In particular, due to the sterilization ability, [ 1 , 2 ] the research and application of AgNPs in biological systems has received widespread attention [ 3 , 4 ]. As we all know, NPs are enshrouded by a layer of biomolecules after being exposed to a biological matrix, generating a novel interface called ‘protein corona’, thus changing the physicochemical properties of NPs to influence their biological effect [ 5 , 6 ].…”