A systematic investigation on the effect of gold nanoparticle morphology and surface functionalization on the differential interaction of HSA was performed.

Amitava Mukherjee

Centre for Nanobiotechnology

Vellore Campus

Chandra Sekaran N

Alex S.A

Chakraborty D

Vellore Institute of Technology (VIT) is a private university located in&nbsp;Tamil Nadu, India. Founded in 1984, as Vellore Engineering College, the institution offers 20 undergraduate, 34 postgraduate, four integrated and four research programs. It has campuses in Vellore, Amravati, Bhopal and Chennai.

VIT is one of the top ranked private universities in India according to NIRF, THE and QS Rankings.&nbsp;Govt. of India has recognized&nbsp;VIT, Vellore as an&nbsp;Institution of Eminence. This has allowed VIT to take independent quality initiatives and move up in world ranking.

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VIT University

RSC Advances

Recently, the concerns about micro- and nano-plastics (NPs) toxicity have been increasing constantly, however the investigations are quiet meager. The present study provides evidences on the toxicological prospectives of virgin-, coronated- and isolated-NPs on human blood cells and Allium cepa root tip, respectively. Several plasma proteins displayed strong affinity towards NPs and produced multi-layered corona of 13 nm to 600 nm size. The coronated-NPs often attracted each other via non-specific protein-protein attraction which subsequently induced protein-induced coalescence in NPs. In the protein point of view, the interaction caused conformational changes and denaturation of protein thereby turned it as bio-incompatible. The coronated-NPs with increased protein confirmation changes caused higher genotoxic and cytotoxic effect in human blood cells than the virgin-NPs. On the other hand, virgin-NPs and the NPs isolated from facial scrubs hindered the root growth and caused chromosome aberration (ring formation, C-mitotic and chromosomal breaks, etc.) in root of Allium cepa. At the outset, the present study highlights the urgent need of scrutinization and regulation of NPs use in medical applications and pre-requisition of additional studies for assessing the bio-accumulation and bio-magnification of NPs. © 2019, The Author(s).

Fulltext

Scientific Reports

Assessment on interactive prospectives of nanoplastics with plasma proteins and the toxicological impacts of virgin, coronated and environmentally released-nanoplastics

Due to the increasing usage of silver nanoparticles in biomedical applications, it becomes important to understand their interaction with biomolecules such as protein. In the present work, we have investigated the interaction of bovine serum albumin (BSA) with silver nanorods (SNRs) using different spectroscopic techniques. The interaction between BSA and SNRs can happen through non-covalent interactions like electrostatic and hydrophobic forces. Upon the interaction of SNRs with various concentrations of BSA, a small red-shift was found in the localized surface plasmon resonance (LSPR) peak of SNRs from UV–visible spectroscopic studies, indicating the adsorption of BSA on the surface of SNRs. The UV–visible absorption spectral studies confirmed the formation of a ground-state BSA-conjugated SNR system. The number of binding sites (n = 1.86) and binding constant (K = 8.719 × 104 L·mol− 1) were obtained to check the strength of conjugation of BSA in presence of different concentrations of SNRs from fluorescence quenching analysis. Further, DLS and zeta potential analyses proved significant binding of BSA towards the SNRs. The secondary structural changes in BSA in the presence of SNRs were obtained using circular dichroism (CD) spectroscopy and Fourier transform infrared spectroscopy (FT-IR). The unfolding behavior of BSA and BSA-conjugated SNR complex were established using the surfactant, sodium dodecyl sulfate (SDS). Finally, the influence of SNRs in the hydrolysis of BSA was investigated by assaying the esterase activity. The esterase activity of BSA was determined by the hydrolysis of p-nitrophenyl acetate (p-NPA) to 4-nitrophenol. © 2017 Elsevier B.V.

Journal of Molecular Liquids

Spectroscopic studies on the interactions of bovine serum albumin in presence of silver nanorods

Gold nanorods (AuNRs) used for biomedical applications could be encountered by biomolecules in the bloodstream, of which IgG is the most abundant antibody. With a view to mitigate their side effect on encountered proteins, the effect of Au concentration (5–40 μM) and functionalization (CTAB-positive;PSS-negative; PEG-neutral) of AuNRs was investigated on the stability of a model protein, IgG (1 μM). Electron microscopic images and particle size analyses indicated least aggregation behavior for PEG-AuNRs, which can be correlated to their neutral charge (from zeta potential analyses) or stearic hindrance of PEG chains. Variations in tryptophan domain were probed by UV–visible absorption and fluorescence quenching studies. Synchronous fluorescence study helped to provide information regarding variations in the hydrophobic region of IgG. The denaturation studies also indicated the stability of AuNR–IgG complex formation. These studies showed that positively charged IgG (pI: 7.8 ± 1.0) was mostly affected by negatively charged PSS-AuNRs and least affected by PEG-AuNRs. This was verified by secondary structural investigations performed using CD and FTIR spectroscopy. For cytotoxicity studies on human lymphocytes, CTAB-AuNRs are known to show higher toxicity compared to PSS-AuNRs and PEG-AuNRs (least). Though PSS-functionalized AuNRs were shown to affect cells to a lesser degree based on the negative charge of cell membrane, they could hamper with positively charged biomolecules in the bloodstream before they reach the target, which must also be considered for choosing the right AuNR functionalization. Thus, this work indicates the effect of different AuNR functionalization on protein and cellular toxicity and stresses the necessity to use neutral particles to mitigate their side effect for theranostic applications. © 2016 Elsevier B.V.

Materials Science and Engineering: C

Significance of surface functionalization of Gold Nanorods for reduced effect on IgG stability and minimization of cytotoxicity

A comprehensive investigation of the differential interaction of human serum albumin with gold nanoparticles based on the variation in morphology and surface functionalization

Increasing knowledge on the biomedical applications of nanoemulsions has necessitated the fundamental understanding behind protein-nanoemulsion interaction. Spectroscopic studies on the binding strategies of biomolecules with serum albumins have been routine for many years to elucidate their binding mechanism cum conformational changes. In the present study, we have investigated the effect of neem oil nanoemulsion of different concentration towards bovine and human serum albumin. Spectroscopic methods such as fluorescence emission, synchronous and three-dimensional spectra, UV-Visible spectroscopy, FTIR and circular dichroism techniques were used. Decrease in fluorescence intensity and controversial hyper-chromicity observed in the UV-Visible spectra of albumins confirmed the ground state complex formation between neem oil nanoemulsion and protein fluorophores. Complex attained remains non-fluorescence and static. Reduced intensity of the peak 1 and peak 2 regions of three-dimensional spectra have recommended the possible effect of nanoemulsion towards the aromatic micro-environment of tryptophan and tyrosine residues. Minor shifts observed in the amide frequency of the FTIR bands at around 1600 cm- 1 corresponds to the possibilities of variation in the secondary alpha-helical structures of biomolecules on interface with nanoemulsion. Decrease in the far UV-CD absorbance cum shift in the dichoric band of molecules at 208 and 222 nm has proportionate the loss of alpha-helical structures. Prominent changes observed in the near UV-CD spectra of biomolecules have also suggested the possible alterations towards tryptophan residues of peptide backbone. © 2015 Elsevier B.V.

Probing the interaction of neem oil based nanoemulsion with bovine and human serum albumins using multiple spectroscopic techniques

Investigation of the transformation of morphology, optical properties, and zeta potential of dumbbell-shaped gold nanorods upon Cr(vi) interaction was performed.

Analytical Methods

Etching-based transformation of dumbbell-shaped gold nanorods facilitated by hexavalent chromium and their possible application as a plasmonic sensor

Since the nanoparticle usage in the biomedical field is increasing, it is necessary to understand their interaction with the biomolecules, such as proteins. The current study primarily investigates the interaction of BSA with the Al2O3 nanoparticles by various spectroscopic techniques. The experiments were carried out in three different experimental matrices, i.e. the distilled de-ionized water, the phosphate buffer and the saline media. The enhanced absorbance observed by UV-visible and fluorescence spectroscopy suggested the probable formation of a ground state complex of the type BSA-Al2O3. The apparent association constant (K app), calculated based on the spectral changes due to the association of BSA with Al2O3 NPs, was found to be higher in an aqueous system (pH 4.47) as compared to the other two matrices, suggesting the maximum interaction between BSA and Al2O3. The particle size analysis of Al2O3 in aqueous suspension demonstrated the possibility of BSA adsorption onto the NP surface. The FT-IR and the circular dichroism (CD) studies indicated that the Al2O3 NPs induced the structural changes in the BSA secondary structure, especially α-helix. © 2013 Elsevier B.V.

Journal	Data powered by TypesetRSC Advances
Publisher	Data powered by TypesetRoyal Society of Chemistry (RSC)
ISSN	20462069
Open Access	0