In this work, a polypyrrole-polyethyleneimine (PPy-PEI) nano-adsorbent was successfully synthesized for the removal of methylene blue (MB) from an aqueous solution. Synthetic dyes are among the most prevalent environmental contaminants. A new conducting polymer-based adsorbent called (PPy-PEI) was successfully produced using ammonium persulfate as an oxidant. The PEI hyper-branched polymer with terminal amino groups was added to the PPy adsorbent to provide more effective chelating sites for dyes. An efficient dye removal from an aqueous solution was demonstrated using a batch equilibrium technique that included a polyethyleneimine nano-adsorbent (PPy-PEI). The best adsorption parameters were measured at a 0.35 g dosage of adsorbent at a pH of 6.2 and a contact period of 40 min at room temperature. The produced PPy-PEI nano-adsorbent has an average particle size of 25–60 nm and a BET surface area of 17 m²/g. The results revealed that PPy-PEI nano-composite was synthesized, and adsorption was accomplished in the minimum amount of time. The maximum monolayer power, qmax, for MB was calculated using the isothermal adsorption data, which matched the Langmuir isotherm model, and the kinetic adsorption data, which more closely fitted the Langmuir pseudo-second-order kinetic model. The Langmuir model was used to calculate the maximum monolayer capacity, or qmax, for MB, which was found to be 183.3 mg g⁻¹. The as-prepared PPy-PEI nano-adsorbent totally removes the cationic dyes from the aqueous solution.

Nanomaterial-based sensors are in demand for early-stage disease detection as a diagnostic tool. Here, we prepare a non-enzymatic electrochemical sensor using hydrothermally synthesized nano-berry shaped cobalt oxide (Co₃O₄) nanostructures on a glassy carbon electrode (GCE). The structural properties, composition, and electrochemical performance of the prepared nanomaterial were characterized. The fabricated non-enzymatic electrochemical sensor (Co₃O₄ nano-berries/GCE) showed excellent sensing performance; for example, high sensitivity (206 μA mM⁻¹ cm⁻²) in a wide detection range (5–3000 μM), and a low limit of detection (∼2.4 μM) towards uric acid. Additionally, we characterized other properties, such as fabrication reproducibility, stability, and selectivity. This work demonstrates the non-enzymatic electrochemical detection of uric acid with high sensing performances. Nano-berry shaped Co₃O₄ nanostructures promoted the sensor performance and prospects in early-stage disease diagnosis.

This investigation reports on the biosorption mechanism of Congo Red dyes (CR) in aqueous solution using acid-treated durian peels, prepared for this study. The biosorbent nature was characterized using the Scanning Electron Microscopy (SEM), Fourier Transform infrared spectroscopy (FT-IR) and Brunaure-Emmet-Teller (BET). The effect of process parameters within operational range of pH (2–9), contact time (10–200 min), initial concentration (25–400 mg g⁻¹) and temperature (25–65 °C) for the optimum removal of CR dyes was investigated using central composite design (CCD) under response surface methodology (RSM), and revealed that the optimum condition of biosorption was achieved around a pH of 5.5, contact time of 105 min at initial concentration of 212.5 mg L⁻¹ within 45 °C temperature, which corresponds to 95.2% percent removal of CR. The experimental data fitted better to the second order polynomial model, with a correlation coefficient R² value of 0.9917 and the Langmuir isotherm model with biosorption capacity of 107.52 mg g⁻¹. Gibbs free energy indicated that the adsorption of CR dyes was spontaneous. The mechanism of the adsorption of CR dyes revealed that the biosorption of CR dyes investigated under different operational conditions show that under acidic pH, the adsorption efficiency of the acid treated durian peels is enhanced for the adsorption of CR dye molecules.

Technology and environmental innovations always have a growing emphasis and have affected various industries. Since the cosmetics industry is highly competitive and consumers always desire innovations in products, the cosmetics industry tends to launch new products to satisfy customer desires without exception. Recently, in the area of cosmeceuticals, the application of nanotechnology has been attempting to increase; however, it seems to be tackling certain disadvantages compared to traditional products. Cosmeceuticals based on nanotechnology offer the benefits of product differentiation, improved bioavailability, and prolonged effects of active ingredients. These are widely used as a regulated delivery medium for cosmeceuticals, such as shampoo, nail enamels, lotions, hair serums, and conditioners. Their wide application is attributed to their intrinsic properties, such as rapid penetration, stability, hydrating power, and texture. The ability of the nanoemulsion system to form small- and large-surface nanoparticles enable the bioactive components to be transported into the skin more effectively. Furthermore, natural cosmetics are a general term that refers to all preparations for external conditioning and beautifying of the body from ingredients produced by or found in nature. The purpose of this review is to understand the nature of natural cosmetics which incorporate nanotechnology for better encapsulation and a better drug delivery system. The importance of innovations in the cosmetic industry is also discussed.

Early-stage uric acid (UA) abnormality detection is crucial for a healthy human. With the evolution of nanoscience, metal oxide nanostructure-based sensors have become a potential candidate for health monitoring due to their low-cost, easy-to-handle, and portability. Herein, we demonstrate the synthesis of puffy balls-like cobalt oxide nanostructure using a hydrothermal method and utilize them to modify the working electrode for non-enzymatic electrochemical sensor fabrication. The non-enzymatic electrochemical sensor was utilized for UA determination using cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The puffy balls-shaped cobalt oxide nanostructure-modified glassy carbon (GC) electrode exhibited excellent electro-catalytic activity during UA detection. Interestingly, when we compared the sensitivity of non-enzymatic electrochemical UA sensors, the DPV technique resulted in high sensitivity (2158 µA/mM.cm²) compared to the CV technique (sensitivity = 307 µA/mM.cm²). The developed non-enzymatic electrochemical UA sensor showed good selectivity, stability, reproducibility, and applicability in the human serum. Moreover, this study indicates that the puffy balls-shaped cobalt oxide nanostructure can be utilized as electrode material for designing (bio)sensors to detect a specific analyte.

Pyrazoles are considered privileged scaffolds in medicinal chemistry. Previous reviews have discussed the importance of pyrazoles and their biological activities; however, few have dealt with the chemistry and the biology of heteroannulated derivatives. Therefore, we focused our attention on recent topics, up until 2020, for the synthesis of pyrazoles, their heteroannulated derivatives, and their applications as biologically active moieties. Moreover, we focused on traditional procedures used in the synthesis of pyrazoles.