The Impact of Surface Functionalization on the Biophysical Properties of Silver Nanoparticles

Abstract

Among metal-based nanoparticles, silver nanoparticles (AgNPs) are particularly appealing because of their stability, functionality, and documented antimicrobial properties. AgNPs also offer the possibility of different surface modifications. In this work, we functionalized AgNPs with thiobarbituric acid or 11-mercaptoundecanoic acid residues to improve the nanoparticles’ biological activities. Subsequently, we assessed the physicochemical properties of newly synthesized AgNPs using a wide range of biophysical methodologies, including UV/vis and fluorescence spectroscopy, atomic force and scanning electron microscopy, and dynamic light scattering and isothermal titration calorimetry. Next, we examined the effect of nanoparticles functionalization on AgNPs mutagenicity and toxicity. Our study revealed that AgNPs’ surface modification affects nanoparticles aggregation, and also impacts nanoparticles’ interaction with model acridine mutagen ICR-191. AgNPs coated with MUA showed the most interesting interactions with tested ICR-191, slightly modulating its toxicity properties by decreasing the viability in treated cells.

Emerging trends in clinical implications of bio-conjugated silver nanoparticles in drug delivery

“…Conversely, the deployment of branched polyethyleneimine (PEI) affords an amine functionality on the surface of AgNPs and equips it with a positive charge [108,109]. Advantageously, the TBA directed carboxylic functionalization also offers clinically exploitable interactions with several proteins residues [114]. Other carboxyl group offering moieties include long-chain unsaturated carboxylates such as oleic acid, elaidic acid, palmitoleic acid, linoleic acid, linolenic acid, and cis-11-eicosenoic acid; where the AgNPs interact with the olefenic positions preferably in a 'cis' configuration and the carboxylic head groups project freely in the colloidal suspension [115].…”

“…Additionally, an effective nanoparticle concentration and their surface functionalization also determines the concomitant physiological toxicity [19]. An effective, yet benign in vivo application of nanoparticles, therefore, requires their conjugation with biologically acceptable molecules or biomolecules [20] or their surface functionalization with physiologically benevolent moieties [21]. AgNP-templated surface functionalization with molecules of interest further extends the prospects of their wide array of clinical applications [22].…”

Nanoparticle Surface Functionalization: How to Improve Biocompatibility and Cellular Internalization

“…The molecules used to modify the NPs surface include small proteins, peptides, antibodies, aptamers, and oligosaccharides (Large et al, 2019;Yoo et al, 2019). Furthermore, the biochemical modification of the NPs surface with these specific targeting ligands is often necessary to reduce toxicity (as widely applied for silver NPs) and to increase their stability in biological fluids (Guerrini et al, 2018;Borowik et al, 2019). An example is represented by the use of human albumin, whose presence on the NPs surface reduces toxicity and achieves active targeting at the same time (Li D. et al, 2018;Sanità et al, 2020).The chemical modification of the NPs surface is a stepby-step process that requires chemical-physical and biological characterization for each step.…”

A New Water-Soluble Thermosensitive Star-Like Copolymer as a Promising Carrier of the Chemotherapeutic Drug Doxorubicin

“…A further temperature increase to 45 • C caused the finishing of the aggregates formation (Table 2). Finally, the particle size distribution can be also derived from the polydispersity index (PDI) value [19]. The registered PDI values > 0.5 indicate a highly polydisperse distribution of the tested samples (Table 2).…”