A precise electrochemical sensor based on Sm2O3/2D TiC hybrid for highly sensitive and selective detection of antihypertensive drug nimodipine

Exploring novel electroanalytical approach using MWCNT nanostructures to quantify nimodipine

A new type of buckypaper of MWCNT with entrapped Nimodipine (NMD) drug was constructed. NMD features a nitroaromatic group that is electroreducible, and a dihydropyridine ring that can be electrooxidized. From the perspective of the nitroaromatic group's reductive capability, we have devised amperometric and voltammetric analytical strategies, including both differential pulse and linear voltammetric techniques. These methods are implemented using glassy carbon electrodes (GCE) modified with buckypaper (BP) disks composed of multiwalled carbon nanotubes (MWCNT), which are capable of adsorbing NMD. Furthermore, by capitalizing on the oxidative capacity of the dihydropyridine ring, we have designed strategies that involve amperometry using screen-printed electrodes (SPE) modified with BP-MWCNT mini discs within a Batch Injection Analysis Cell (BIAS) designed for SPE. The developed sensor was applied successfully to determine the drug in commercial tablets. The analytical parameters of this sensor were adequate, with a recovery value of 98.24 % and detection and quantification limits of 7.01 mgL-1 and 23.35 mgL-1, respectively using the DPV method.

Synergistic effect of a bamboo-like Bi2S3 covered Sm2O3 nanocomposite (Bi2S3-Sm2O3) for enhanced alkaline OER

The availability of hydrogen energy from water splitting through the electrocatalytic route is strongly dependent on the efficiency, durability, and cost of the electrocatalysts. Herein, a novel Bi2S3-covered Sm2O3 (Bi2S3-Sm2O3) nanocomposite electrocatalyst was developed by a hydrothermal route for the oxygen evolution reaction (OER). The electrochemical properties were studied in 1.00 mol KOH solution after coating the target material on the stainless-steel substrate (SS). Physical analysis via XRD, FTIR, IV, TEM/EDX, and XPS revealed that the Bi2S3-Sm2O3 composite possesses metallic surface states, thereby displaying unconventional electron dynamics and purity of phases. The Bi2S3-Sm2O3 composite shows outstanding OER activity with a low overpotential of 197 mV and a Tafel slope of 74 mV dec-1 at a 10 mA cm-2 current density as compared to pure Bi2S3 and Sm2O3. Meanwhile, the composite catalyst retains high stability even after 100 h of the chronoamperometry test. Thus, this work unveils a new avenue for the speedy flow of electrons, which is attributed to the synergetic effect between Bi2S3 and Sm2O3, as well as enriched interfacial defects, which exhibit greater oxygen adsorption capability with improved electronic assemblies in the active interfacial region. In addition, the introduced porous structure in core-shell Bi2S3-Sm2O3 provides extraordinary electrical properties. Thus, this article offers a realistic framework for electrochemical energy generation.

Highly responsive and sensitive non-enzymatic electrochemical sensor for the detection of β-NADH in food, environmental and biological samples using AuNP on polydopamine/titanium carbide composite

In this study, a polydopamine/titanium carbide adorned with gold nanoparticles (Au@PDA/TiC) composite was prepared by a simple stirring technique and it was used for the dual-technique detection of β-Nicotinamide adenine dinucleotide (NADH). The Au@PDA/TiC-modified glassy carbon electrode (GCE) oxidized NADH at a very low oxidation potential of approximately 0.60 V vs Ag/AgCl in pH = 7.0 (0.1 M PBS) via the transfer of two electrons and one proton (from NADH to NAD⁺). Based on the (i-t) amperometry mode, NADH can be quantified with a linear range of 0.018-674 μM and LOD of 0.0062 µM. In addition to the DPV mode, the electrochemical sensor had a linearity of 5-450 µM with a LOD of 3.17 µM. The developed sensor exhibited remarkable analytical performances concerning high sensitivity, electrocatalytic activity, low detection limit, wide linearity, appreciable specificity, repeatability, stability, reproducibility, and adequate recovery results in food, environmental and biological samples.

2D MXene-Based Biosensing: A Review

MXene emerged as decent 2D material and has been exploited for numerous applications in the last decade. The remunerations of the ideal metallic conductivity, optical absorbance, mechanical stability, higher heterogeneous electron transfer rate, and good redox capability have made MXene a potential candidate for biosensing applications. The hydrophilic nature, biocompatibility, antifouling, and anti-toxicity properties have opened avenues for MXene to perform in vitro and in vivo analysis. In this review, the concept, operating principle, detailed mechanism, and characteristic properties are comprehensively assessed and compiled along with breakthroughs in MXene fabrication and conjugation strategies for the development of unique electrochemical and optical biosensors. Further, the current challenges are summarized and suggested future aspects. This review article is believed to shed some light on the development of MXene for biosensing and will open new opportunities for the future advanced translational application of MXene bioassays.

Highlighting the Compositional Changes of the Sm2O3/MgO-Containing Cellulose Acetate Films for Wound Dressings

The development of wound dressing materials with appropriate specifications is still a challenge to overcome the current limitations of conventional medical bandages. In this regard, simple and fast methods are highly recommended, such as film casting. In addition, deliverable nanoparticles that can act to accelerate wound integration, such as samarium oxide (Sm₂O₃) and magnesium oxide (MgO), might represent a potential design with a novel compositional combination. In the present research, the casted film of cellulose acetate (CA) was mixed with different ratios of metal oxides, such as samarium oxide (Sm₂O₃) and magnesium oxide (MgO). The tests used for the film examination were X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). The SEM graphs of CA films represent the surface morphology of Sm₂O₃@CA, MgO@CA, and Sm₂O₃/MgO/GO@CA. It was found that the scaffolds' surface contained a high porosity ratio with diameters of 1.5-5 µm. On the other hand, the measurement of contact angle exhibits a variable trend starting from 27° to 29° for pristine CA and Sm₂O₃/MgO/GO@CA. The cell viability test exhibits a noticeable increase in cell growth with a decrease in the concentration. In addition, the IC₅₀ was determined at 6 mg/mL, while the concentration of scaffolds of 20 mg/mL caused cellular growth to be around 106%.