Zinc oxide nanoparticles decorated nitrogen doped porous reduced graphene oxide-based hybrid to sensitive detection of hydroxychloroquine in plasma and urine.

The antimalarial hydroxychloroquine (HCQ) has considered for the treatment of systemic lupus erythematosus. Moreover, HCQ has been used as a drug to treat Coronavirus disease (COVID-19). In this work, nitrogen doped porous reduced graphene oxide (NprGO) has been prepared via environmentally friendly process using Fummaria Parviflora extract.

An ordered mesoporous carbon-silica hybrid for the detection of the antiviral drug ribavirin in clinical samples.

Ribavirin (RIB) is widely used for the treatment of viral diseases such as herpes, hepatitis C, and Lassa fever. Moreover, to control the spread of COVID-19, the consumption of antiviral medicines, including RIB, has increased significantly worldwide. By combining ordered mesoporous carbon with silica nanoparticles ultrasound, we synthesized silica/ordered mesoporous carbon (SiO-OMC) hybrid composites that show excellent electrochemical performance.

Cu-Co Bimetallic Catalyst-based Electrochemical Sensing Platform for Determination of Bisoprolol in Clinical Samples.

Background: Bisoprolol (BIS) is a selective beta-blocker. It has been successfully used to treat hypertension and angina pectoris. An overdose of BIS can lead to serious complications.

Conjugation of Doxorubicin and Carbon-based-nanostructures for Drug Delivery against HT-29 Colon Cancer Cells.

Background: A drug delivery system is the method or process of administering a pharmaceutical compound to achieve a therapeutic effect in humans or animals. Such systems release the drugs at specific amounts in a specific site. The carbon based-nanomaterials have been actively used as drug carriers to treat various cancer.

Magnetite graphene oxide-albumin conjugate: carrier for the imatinib anticancer drug.

Carbon nanomaterials are widely used in biomedical applications due to their versatile properties. These are the attractive candidates for the carrying of anticancer drugs, genes, and proteins for chemotherapy. Imatinib is an effective chemotherapy drug whose toxicity has created a significant limitation in treatment.

Application of graphene oxide in the adsorption and extraction of bioactive compounds from lemon peel.

The bioactive compounds like rutin, naringin, and gallic acid have been separated from lemon peel by graphene oxide (GO). The different influences such as pH values and separation conditions were investigated. Moreover, the samples were characterized by Fourier transform infrared spectroscopy, thermogravimetric analysis, scanning electron microscopy, UV-Vis spectroscopy, and high-performance liquid chromatography.

Colorimetric assay based on horseradish peroxidase/reduced graphene oxide hybrid for sensitive detection of hydrogen peroxide in beverages.

We reported a simple and sensitive colorimetric assay for detection of hydrogen peroxide (HO) based on the oxidation of 2,2׳-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) by UV-Vis spectroscopy method. The reduced graphene oxide (rGO) was prepared using green tea extract as bio-reducing and stabilizer agent and decorated by horseradish peroxidase (HRP). The surface of Au interface was modified with HRP-rGO hybrid.

Green tea extract assisted green synthesis of reduced graphene oxide: Application for highly sensitive electrochemical detection of sunset yellow in food products.

The search to find simple, cost-effective, environmentally friendly method for synthesising of reduced graphene oxide (rGO) has motivated the use of various natural materials. Also, monitoring of sunset yellow (SY) level in foods due to the potential negative side effects is imperative. In this study, tea extract was explored as reducing and stabilizing agent for synthesising of rGO.

Electrochemical sensor based on magnetite graphene oxide/ordered mesoporous carbon hybrid to detection of allopurinol in clinical samples.

Allopurinol (ALO) is a radical scavenging clinical drug, a drug in the treatment of gout, an inhibitor of xanthine oxidase and an effective agent for anti-cancer purposes. The xanthine oxidase is thus essential, and the amount of ALO needs to be controlled more strictly. In this study, a new electrochemical sensor based on magnetite graphene oxide/ordered mesoporous carbon (FeO@GO/OMC) hybrid was prepared and characterized.

Dopamine-functionalized cyclodextrins: modification of reduced graphene oxide based electrodes and sensing of folic acid in human serum.

A mandatory step in any sensor fabrication is the introduction of analyte-specific recognition elements to the transducer surface. In this study, the possibility to anchor β-cyclodextrin-modified dopamine to a reduced graphene oxide based electrochemical transducer for the sensitive and selective sensing of folic acid is demonstrated. The sensor displays good electrocatalytic activity toward the oxidation of folic acid.

Graphene-modified electrodes for sensing doxorubicin hydrochloride in human plasma.

Doxorubicin (DOX), an anthracycline molecule, is currently one of the most widely used anticancer drugs in clinics. Systematic treatment of patients with DOX is known to be accompanied by several unpleasant side effects due to the toxicity of the drug. Thus, monitoring of DOX concentration in serum samples has become increasingly important to avoid side effects and ensure therapeutic efficiency.

On demand electrochemical release of drugs from porous reduced graphene oxide modified flexible electrodes.

Despite the advantages of an electrochemical control for drug release, only a handful of electrochemical-based release systems have been developed so far. We report herein on the development of an electrochemically activatable platform for on-demand delivery of drugs. It is based on flexible gold thin film electrodes coated with porous reduced graphene oxide (prGO) nanosheets onto which the drug of interest has been integrated beforehand.

A sensitive voltammetric detection of pramipexole based on 1,1,3,3-tetramethyldisilazanecarbon nanotube modified electrode.

A simple low-cost method is proposed to fabricate a functionalized multi-wall carbon nanotube (MWCNT) with 1,1,3,3-tetramethyldisilazane (TMDS) molecule. The techniques of scanning electron microscope (SEM) with electron diffraction and energy dispersive X-ray (EDAX) analysis were applied to characterize the functionalized TMDS-MWCNT. The results showed that a MWCNT with high functionalization of TMDS can be obtained using this simple method.

MoS/reduced graphene oxide nanocomposite for sensitive sensing of cysteamine in presence of uric acid in human plasma.

A hybrid nanocomposite of MoS nanosheets and reduced graphene oxide (rGO) was fabricated by a facile and effective method. The morphology and structure of the nanocomposite (MoS-rGO) were characterized by scanning electron microscopy, X-ray photoelectron spectroscopy, Raman spectroscopy, electrochemical impedance spectroscopy and cyclic voltammetry. The MoS nanosheets were uniformly anchored on the rGO framework with strong adhesion.

MoS2/reduced graphene oxide as active hybrid material for the electrochemical detection of folic acid in human serum.

In this study, a new matrix based on a molybdenum disulfide-reduced graphene oxide hybrid (MoS2-rGO) was prepared and characterized. Modification of a glassy carbon electrode (GCE) with MoS2-rGO (MG) using drop casting allowed for the selective analysis of folic acid in the presence of a variety of interference species with a limit of detection of 10nM, a linear range between 0.01μM and 100μM with a sensitivity of 14µAµM(-1).

The ultrasound-assisted aqueous extraction of rice bran oil.

In this work, aqueous extraction of rice bran oil was done without and with ultrasound pretreatment. Key factors controlling the extraction and optimal operating conditions were identified. The highest extraction efficiency was found at pH=12, temperature of 45°C, agitation speed of 800rpm and agitation time of 15min, ultrasound treatment time of 70min and ultrasound treatment temperature of 25°C.

Direct and mediated electrochemistry of peroxidase and its electrocatalysis on a variety of screen-printed carbon electrodes: amperometric hydrogen peroxide and phenols biosensor.

This study compares the behaviour of direct and mediated electrochemistry of horseradish peroxidase (HRP) immobilised on screen-printed carbon electrodes (SPCEs), screen-printed carbon electrodes modified with carboxyl-functionalised multi-wall carbon nanotubes (MWCNT-SPCEs) and screen-printed carbon electrodes modified with carboxyl-functionalised single-wall carbon nanotubes (SWCNT-SPCEs). The techniques of cyclic voltammetry and amperometry in the flow mode were used to characterise the properties of the HRP immobilised on screen-printed electrodes. From measurements of the mediated and mediatorless currents of hydrogen peroxide reduction at the HRP-modified electrodes, it was concluded that the fraction of enzyme molecules in direct electron transfer (DET) contact with the electrode varies substantially for the different electrodes.

Direct electrochemistry and bioelectrocatalysis of a class II non-symbiotic plant haemoglobin immobilised on screen-printed carbon electrodes.

In this study, direct electron transfer (ET) has been achieved between an immobilised non-symbiotic plant haemoglobin class II from Beta vulgaris (nsBvHb2) and three different screen-printed carbon electrodes based on graphite (SPCE), multi-walled carbon nanotubes (MWCNT-SPCE), and single-walled carbon nanotubes (SWCNT-SPCE) without the aid of any electron mediator. The nsBvHb2 modified electrodes were studied with cyclic voltammetry (CV) and also when placed in a wall-jet flow through cell for their electrocatalytic properties for reduction of H(2)O(2). The immobilised nsBvHb2 displayed a couple of stable and well-defined redox peaks with a formal potential (E°') of -33.

The interaction between ketamine and some crown ethers in common organic solvents studied by NMR: the effect of donating atoms and ligand structure.

1H NMR spectroscopy was used to investigate the stoichiometry and stability of the drug ketamine cation complexes with some crown ethers, such as 15-crown-5 (15C5), aza-15-crown-5 (A15C5), 18-crown-6 (18C6), aza-18-crown-6 (A18C6), diaza-18-crown-6 (DA18C6), dibenzyl-diaza-18-crown-6 (DBzDA18C6) and cryptant [2,2,2] (C222) in acetonitrile (AN), dimethylsulfoxide (DMSO) and methanol (MeOH) at 27 degrees C. In order to evaluate the formation constants of the ketamine cation complexes, the CH3 protons chemical shift (on the nitrogen atom of ketamine) was measured as function of ligand/ketamine mole ratio. The formation constant of resulting complexes were calculated by the computer fitting of chemical shift versus mole ratio data to appropriate equations.