Glutathione-Modified Gold Nanoparticles Research Articles

Fabrication of glutathione-modified gold nanoparticles as 3-chloropropane-1,2-diol sensor

Refined palm oil products may contain a harmful substance called as 3-monochloropropane-1,2-diol (3-MCPD), which can potentially be carcinogenic if consumed in excess. The determination of 3-MCPD depends on the sophisticated machine and highly skilled technicians but it is time-consuming. A simple method that proposes rapid detection remains a challenge. Hence, this research aims to develop a colorimetric-based rapid detection sensor using gold nanoparticles functionalized with a ligand, glutathione (GSH) to be bound to 3-MCPD. Varied concentrations of GSH were evaluated to obtain stable GSH-AuNPs. The characterization results showed that the composition of the stable GSH-AuNPs has been achieved by 250 µL of 0.02 M GSH addition. A stable GSH-AuNPs was ruby red with surface plasmon resonance (SPR) band at 520 nm and an average nanoparticle size of 30 nm. The indication for detection of 3-MCPD was marked by the decrease in the absorbance intensity. Thus, GSH-AuNPs have potential to be developed for the 3-MCPD sensor application.

Linalool-Loaded Glutathione-Modified Gold Nanoparticles Conjugated with CALNN Peptide as Apoptosis Inducer and NF-κB Translocation Inhibitor in SKOV-3 Cell Line.

BackgroundLinalool is a monoterpene compound with various potential therapeutic applications in several medical fields. Previous studies have indicated the activity of linalool against cell lines; however, its high level of toxicity restricts its use. The aim of this study was to design and manufacture compounds with a novel structure that can be used for loading linalool, to reduce its toxicity and improve its reachable ability.MethodsWe synthesized and characterized a new molecule for loading linalool onto gold nanoparticles (GNPs) capped with glutathione and conjugated with a CALNN peptide. Linalool was loaded onto the GNPs via the reaction of the surface groups of both linalool and the GNPs. Moreover, the target peptide could be loaded onto the surface of the GNPs via a chemical reaction. The cytotoxic effects of linalool–GNP (LG) and linalool–GNP–CALNN peptide (LGC) conjugates against ovarian cancer cells were investigated, as were the possible mechanisms underlying the induction of apoptosis.ResultsOur findings illustrated the significant antiproliferative effect of LG and LGC on SKOV-3 cells. The cytotoxicity assay demonstrated that LG and LGC were selectively toxic in cancer cells and induced apoptosis by activating caspase-8, the p53 protein, and various proteins involved in apoptosis. The present data demonstrated that LG and LGC have a high therapeutic potential and should be given particular consideration as anticancer drug-delivery systems, as LG and LGC were remarkably more cytotoxic against a cancer cell line than were linalool and GNPs alone.ConclusionWe concluded that LG and LGC are promising compounds that can be used for treating ovarian cancer (SKOV-3) cells via the induction of apoptosis through extrinsic and intrinsic pathways.

Ultrasensitive detection of lead (II) ion by dark-field spectroscopy and glutathione modified gold nanoparticles

Exposure to trace amounts of lead is known to harm human health, especially for children, which results in irreversible detriment to brain and nerve development. However, most of the sensor platforms using the colorimetric method to detect lead (II) ions (Pb2+) are difficult to reach a decent limit of detection (LOD) and a large detection range. This work presents a practical method to detect Pb2+ in aqueous-medium with the help of single-particle dark field spectroscopy, which allows us to obtain good LOD and wide detection range. Our results illustrate that the glutathione functionalized AuNPs are able to capture free AuNPs in the presence of Pb2+ to form multipliers. Such a process results in a significant spectral redshift of scattering spectra due to plasmonic coupling, which allows us to reach a good LOD of 3.5 pM, and a large linear quantifiable detection range from 10 pM to 10 μM. The performance of our sensor platform provides an alternative way to detect traces of Pb2+ in real-life water samples.

Evaluation of flutamide loading capacity of biosynthesis of plant-mediated glutathione-modified gold nanoparticles by Dracocephalum Kotschyi Boiss extract

In this research, the biosynthesis of glutathione-modified gold nanoparticles was investigated and evaluation of modified nano-adsorbent for its application in loading of flutamide (FLUT) was also performed. Gold nanoparticles (AuNPs) were synthesized in the presence of the Dracocephalum Kotschyi Boiss extract. The response surface methodology (RSM) based on central composite design was used to evaluate and optimize the effect of main factors. The significance of the independent variables and their interactions was tested by means of analysis of variance with 95% confidence level. Results showed that the extract volume, volume of nanogold solution, temperature, extraction time and pH of the sample solution were the main parameters affecting flutamide loading capacity. The optimum operating conditions to achieve maximum loading capacity were determined. The synthesis of AuNPs was confirmed using ultraviolet–visible spectroscopy, FT-IR spectroscopy and X-ray diffraction. The scanning electron microscope (SEM) showed that gold nanoparticles were spherical in size in the range of 30–70 nm. The surface of nanoparticles was chemically modified by glutathione to enhance the bio-stability of the gold nanoparticles and proper interaction between nanoparticles and FLUT. The absence of a peak of 2520.70 cm−1 related to S–H bond in the spectrum of glutathione-modified gold nanoparticles was indicative of the formation of a bond between the sulfur atom and the AuNPs. In the FT-IR spectrum of flutamide-loaded glutathione-modified gold nanoparticles, all the specific peaks of flutamide were observed.

Linalool loaded on glutathione-modified gold nanoparticles: a drug delivery system for a successful antimicrobial therapy

In the present study, antimicrobial activity of Linalool loaded on Glutathione-modified Gold nanoparticles prepared by novel method was investigated. The aim of this study is to evaluate the antimicrobial activity of Linalool-gold nanoparticles (LIN-GNPs) against Gram's positive bacteria Staphylococcus aureus, Gram's negative bacteria Escherichia coli, and against Leishmania tropica. Gold nanoparticles were synthesized using the chemical method. Colour change, UV–Vis spectrum, FTIR and SEM confirmed the characterization of gold nanoparticles and LIN-GNPs. The antibacterial study was including agar well diffusion method, MIC, MBC. The mode of action was determined by cellular material release assay, SEM and AO/EtBr for ROS detection. Anti-parasitic activity was evaluated using MTT assay. FTIR spectral analysis investigated that Linalool was loaded on gold nanoparticles. SEM showed that the Gold nanoparticles and LIN-GNPs were generally found to be spherical in shape and the size was ranged 5–11 nm for GNPs and 15–20 nm for LIN-GNPs. The results of antibacterial activity demonstrated that Linalool alone had low activity against gram-positive and gram-negative bacteria. While the results showed that gram-positive bacteria were more effective by LIN-GNPs. LIN-GNPs acted on the bacterial cell membrane, resulting in loss of integrity and increased permeability of cell wall and stimulated ROS production that leads to damage of bacterial nucleic acid. The anti-parasitic activity results indicated the high activity of LIN-GNPs on L. tropica compared with Linalool and Gold nanoparticles. These results proved that LIN-GNPs have great potential as antimicrobial activity and could be used as a developing strategy for a successful antimicrobial therapeutic agent.

Fabrication of an interferon-gamma-based ITO detector for latent tuberculosis diagnosis with high stability and lower cost

Interferon-gamma (IFN-γ) released by T cells performs very important roles in latent diagnosis of Mycobacterium tuberculosis (MTB) infections and control of tuberculosis. In this work, a multilayer screen printing indium tin oxide (ITO) detector modified with a self-assembled graphene/chitosan (Gr-Chit) composite film followed by glutathione-modified gold nanoparticles (GSH-AuNPs), antibodies, and antigens was fabricated for highly sensitive and rapid detection of IFN-γ. The formation of the antibody-antigen complex at the electrode surface causes the impedance to increase. Under optimum conditions, the relative increased differential pulse voltammetry (DPV) peak current values are proportional to the logarithmic value of IFN-γ concentrations in a wide range of 5 to 4000 pg/mL with a low detection limit of 0.5 pg/mL (S/N = 3). The resulting IFN-γ immunosensor shows excellent detection reproducibility, good specificity, and stability. In addition, for the detection of clinical serum samples, it is well consistent with the standard enzyme-linked immunosorbent assay (ELISA) tests. Compared to the expensive glassy carbon electrode, the ITO detector can act as a disposable electrode in clinical detection due to its low cost. This study provides a lower cost, simple, and highly sensitive approach for potential application in early diagnosis of MTB infections and control of tuberculosis.

Glutathione Dimerization-Based Plasmonic Nanoswitch for Biodetection of Reactive Oxygen and Nitrogen Species

Reactive oxygen and nitrogen species (ROS and RNS) are continuously produced in the cellular systems and are controlled by several antioxidant mechanisms. Here, we developed a straightforward, sensitive, and quantitative assay for the colorimetric and spectroscopic detection of various ROS and RNS such as H2O2, ·OH, (-)OCl, NO·, and O2(-) using glutathione-modified gold nanoparticles (GSH-AuNPs). A basic principle here is that the GSHs on the AuNP surface can be readily detached via the formation of glutathione disulfides upon the addition of ROS and RNS, and destabilized particles can aggregate to generate the plasmonic couplings between plasmonic AuNPs that trigger the red shift in UV-vis spectrum and solution color change. For nonradical species such as H2O2, this process can be more efficiently achieved by converting them into radical species via the Fenton reaction. Using this strategy, we were able to rapidly and quantitatively distinguish among cancerous and normal cells based on ROS and RNS production.