Simple potentiometry and cyclic voltammetry techniques for sensing Hg2+ ions in water using a promising flower-shaped WS2-WO3/poly-2-aminobenzene-1-thiol nanocomposite thin film electrode.

A highly promising flower-shaped WS2-WO3/poly-2-aminobenzene-1-thiol (P2ABT) nanocomposite was successfully synthesized via a reaction involving 2-aminobenzene-1-thiol, Na2WO4, and K2S2O8 as oxidants. The WS2-WO3/P2ABT nanocomposite demonstrated remarkable potential as a sensor for detecting harmful Hg2+ ions in aqueous solutions. The sensing behavior was evaluated over a wide concentration range, from 10-6 to 10-1 M, using a simple potentiometric study on a two-electrode cell. The calibration curve yielded an excellent Nernstian slope of 33.0 mV decade-1. To further validate the sensing capabilities, cyclic voltammetry was employed, and the results showed an increasing trend in the cyclic voltammetry curve as the Hg2+ concentration increased from 10-6 to 10-1 M with an evaluated sensitivity of 2.4 µA M-1. The WS2-WO3/P2ABT nanocomposite sensor exhibited exceptional selectivity for detecting Hg2+ ions, as no significant effects were observed from other interfering ions such as Zn2+, Ni2+, Ca2+, Mg2+, Al3+, and K+ ions in the cyclic voltammetry tests. Furthermore, the sensor was tested on a natural sample that was free of Hg2+ ions, and the cyclic voltammetry curves did not produce any characteristic peaks, confirming the sensor's specificity for Hg2+ detection. The sensor's cost-effectiveness and ease of fabrication present the potential for developing a simple and practical sensor for detecting highly poisonous ions in aqueous solutions.

Decoration of Poly-3-methyl Aniline with As(III) Oxide and Hydroxide as an Effective Photoelectrode for Electroanalytical Photon Sensing with Photodiode-like Behavior.

This study achieved the decoration of poly-3-methyl aniline (P3MA) with As2O3-As(OH)3 using K2S2O8 and NaAsO2 on the 3-methyl aniline monomer. This resulted in a highly porous nanocomposite polymer composite with wide absorption optical behavior, an average crystalline size of 22 nm, and a 1.73 eV bandgap. The photoelectrode exhibited a great electrical response for electroanalytical applications, such as photon sensing and photodiodes, with a Jph of 0.015 mA/cm2 and Jo of 0.004 mA/cm2. The variable Jph values ranged from 0.015 to 0.010 mA/cm2 under various monochromatic filters from 340 to 730 nm, which demonstrates high sensitivity to wavelengths. Effective photon numbers were calculated to be 8.0 × 1021 and 5.6 × 1021 photons/s for these wavelength values, and the photoresponsivity (R) values were 0.16 and 0.10 mA/W, respectively. These high sensitivities make the nanocomposite material a promising candidate for use in photodetectors and photodiodes, with potential for commercial applications in highly technological systems and devices. Additionally, the material opens up possibilities for the development of photodiodes using n- and p-type materials.

Corrosion Behavior of Aluminium-Coated Cans.

Hundreds of billions of aluminium-based cans are manufactured and used every year worldwide including those containing soft drinks. This study investigates and evaluates the performance and quality of two well-known energy and soft drinks brands, Green Cola and Red Bull. Recent health hazards and concerns have been associated with aluminium leakage and bisphenol A (BPA) dissociation from the can's internal protective coating. The cans were examined under four conditions, including coated and uncoated samples, the soft drink's main solution, and 0.1 M acetic acid solution. Electrochemical measurements such as potentiodynamic polarization and impedance spectroscopy (EIS), element analyses using inductively coupled plasma optical emission spectrometry (ICP-OES), and energy dispersive X-ray spectroscopy (EDS) were performed. In addition, sample characterization by scanning electron microscopy (SEM) and X-ray diffraction spectroscopy (XRD) were employed to comprehensively study and analyze the effect of corrosion on the samples. Even though the internal coating provided superior corrosion protection concerning main or acetic acid solutions, it failed to prevent aluminium from dissolving in the electrolyte. Green Cola's primary solution appears to be extremely corrosive, as the corrosion rate increased by approximately 333% relative to the acetic acid solution. Uncoated samples resulted in increases in the percentage of oxygen, the appearance of more corrosion spots, and decreases in crystallinity. The ICP-OES test detected dangerous levels of aluminium in the Green Cola solution, which increased significantly after increasing the conductivity of the solution.

Evaluation of Heavy Metals in Soil Wastewater Stream.

Environmental pollution is one of the main factors that significantly affect biological systems and human health. Soil pollution with heavy metals is an increasingly pressing problem worldwide. In general, heavy metals are stable and do not decompose, unlike other organic pollutants. The quantity of them is natural components of soil crust, the remaining come from human activities, which may result from the extensive use of sewage. In the present study, a methodology aimed at simultaneous quantification of 16 heavy elements in soil of 3 different regions was developed. The concentration of 16 soil heavy metals (Se, Cd, V, Be, As, Mn, Co, Zn, Fe, Cr, Pb, Ni, Cu, Mo, Hg, and Ti) was measured in 11 sampling along Riyadh, Qassim, and Medina, Kingdom of Saudi Arabia from 3 sites soil treated with sewage water. These chemical minerals were identified in the samples using an ICPE-9000 spectrometer. The assessment of heavy metal contamination was derived using enrichment factors (EF), the pollution load index (PLI), and geoaccumulation index (I geo). This study revealed that the soil is predominantly polluted by Cd, As, and Mo of Riyadh and Medina and As, Mo, and Cd of Qassim region at site B and site C, respectively. As recorded, the highest concentration value of 5000 mg/kg for Fe at site (B) followed by Cu. The I geo value of Cd is 1.1520 in Medina region. The I geo value of Se is 3.2395 in Medina region, while its cumulative geographical index decreased in the regions of Riyadh and Qassim, which amounted to 2.6114 and 2.1699, respectively. The I geo values of the rest of the minerals in the three regions studied indicated that the soil is unpolluted, while it was slightly to moderately polluted for both Mo and Hg in most regions studied. The minerals in the soil at all sites studied were less than the general average concentration. With the exception of mercury, molybdenum, arsenic, cadmium, and selenium, whose concentration exceeded the permissible and recommended limits. The increasing order of concentration of minerals was Be < V < Cd < Hg < Mo < Co < Zn < Pb < Cr < Se < As < Ni < Ti < Mn < Cu < Fe at all sites, respectively.

A Brief Assessment on Recent Developments in Efficient Electrocatalytic Nitrogen Reduction with 2D Non-Metallic Nanomaterials.

In recent years, the synthesis of ammonia (NH3) has been developed by electrocatalytic technology that is a potential way to effectively replace the Haber-Bosch process, which is an industrial synthesis of NH3. Industrial ammonia has caused a series of problems for the population and environment. In the face of sustainable green synthesis methods, the advantages of electrocatalytic nitrogen reduction for synthesis of NH3 in aqueous media have attracted a great amount of attention from researchers. This review summarizes the recent progress on the highly efficient electrocatalysts based on 2D non-metallic nanomaterial and provides a brief overview of the synthesis principle of electrocatalysis and the performance measurement indicators of electrocatalysts. Moreover, the current development of N2 reduction reaction (NRR) electrocatalyst is discussed and prospected.

Experimental and Computational Analysis of Newly Synthesized Benzotriazinone Sulfonamides as Alpha-Glucosidase Inhibitors.

Diabetes mellitus is a chronic metabolic disorder in which the pancreas secretes insulin but the body cells do not recognize it. As a result, carbohydrate metabolism causes hyperglycemia, which may be fatal for various organs. This disease is increasing day by day and it is prevalent among people of all ages, including young adults and children. Acarbose and miglitol are famous alpha-glucosidase inhibitors but they complicate patients with the problems of flatulence, pain, bloating, diarrhea, and loss of appetite. To overcome these challenges, it is crucial to discover new anti-diabetic drugs with minimal side effects. For this purpose, benzotriazinone sulfonamides were synthesized and their structures were characterized by FT-IR, 1H-NMR and 13C-NMR spectroscopy. In vitro alpha-glucosidase inhibition studies of all synthesized hybrids were conducted using the spectrophotometric method. The synthesized compounds revealed moderate-to-good inhibition activity; in particular, nitro derivatives 12e and 12f were found to be the most effective inhibitors against this enzyme, with IC50 values of 32.37 ± 0.15 µM and 37.75 ± 0.11 µM. In silico studies, including molecular docking as well as DFT analysis, also strengthened the experimental findings. Both leading compounds 12e and 12f showed strong hydrogen bonding interactions within the enzyme cavity. DFT studies also reinforced the strong binding interactions of these derivatives with biological molecules due to their lowest chemical hardness values and lowest orbital energy gap values.

Comparative Evaluation of Various Extraction Techniques for Secondary Metabolites from Bombax ceiba L. Flowering Plants along with In Vitro Anti-Diabetic Performance.

Bombax ceiba L. (Family: Malvaceae) was rightly called the "silent doctor" in the past as every part of it had medicinal value. For centuries, humans have used this plant according to the traditional medicinal systems of China, Ayurveda, and tribal communities. Recently, with an emerging interest in herbals, attention has been paid to scientifically validating medicinal claims for the treatment of diabetes using secondary metabolites of B. ceiba L. flowers. In the present study, specific secondary metabolites from the flowers of B. ceiba L. were isolated in good yield using the solvent extraction methodology, and their in vitro anti-diabetic efficacy was examined. Extraction efficiency of each solvent for secondary metabolites was found in following order: water > ethanol> methanol > chloroform > petroleum ether. Quantitative analysis of secondary metabolites showed 120.33 ± 2.33 mg/gm polyphenols, 60.77 ± 1.02 mg/g flavonoids, 60.26 ± 1.20 mg/g glycosaponins, 0.167 ± 0.02 mg/g polysaccharides for water extract; 91.00 ± 1.00 mg/g polyphenols, 9.22 ± 1.02 mg/g flavonoids, 43.90 ± 0.30 mg/g glycosaponins, 0.090 ± 0.03 mg/g poly saccharides for ethanol extract; 52.00 ± 2.64 mg/g polyphenols, 35.22 ± 0.38 mg/g flavonoids, 72.26 ± 1.05 mg/g glycosaponins, 0.147 ± 0.01 mg/g polysaccharides for methanol extract; 11.33 ± 0.58 mg/g polyphenols, 23.66 ± 1.76 mg/g flavonoids, 32.8 ± 0.75 mg/g glycosaponins, 0.013 ± 0.02 mg/g polysaccharides for chloroform extract; and 3.33 ± 1.53 mg/g polyphenols, 1.89 ± 1.39 mg/g flavonoids, 21.67 ± 1.24 mg/g glycosaponins, 0.005 ± 0.01 mg/g polysaccharides for petroleum ether extract. Glucose uptake by yeast cells increased 70.38 ± 2.17% by water extract.

Formulation, In Vitro Characterization and Antibacterial Activity of Chitosan-Decorated Cream Containing Bacitracin for Topical Delivery.

(1) Background: Bacitracin is a broad spectrum antibiotic that is used against various microorganisms. Chitosan is a natural polymer that has been widely investigated as an antimicrobial agent for preventing and treating infections owing to its intrinsic antimicrobial properties, as well as its ability to effectively deliver extrinsic antimicrobial compounds to infected areas. Topical drug delivery offers important benefits for improving the therapeutic effect and reducing systemic side effects of administered compounds/drugs. The topical use of chitosan-decorated bacitracin-loaded cream improves the permeation of the drug across the skin and enhances the drug bioavailability by prolonging the residence time of the drug when applied topically, as well as producing synergistic effects and reducing the side effects of the drug. Topical chitosan-decorated cream can be a promising approach to administer the drug more efficiently and enhance the efficacy of treatment in wound healing and antibacterial activity. (2) Methods: This study was conducted to prepare, assess and investigate the synergistic antibacterial activity of a chitosan-coated bacitracin cream. The results were compared to the antibacterial activity of simple bacitracin-loaded cream. The prepared cream was evaluated for various in vitro characteristics such as rheology, pH, viscosity, drug content and antibacterial activity studies. (3) Result: The formulations were found to be stable regarding color, liquefaction and phase separation at all accelerated conditions. It was observed that with time, substantial variations in the pH of the preparations were found. The introduction of chitosan results in controlled release of the drug from the formulations. The antibacterial activity of the formulated creams was assessed with the disc diffusion method against Staphylococcus aureus(ATCC),Escherichiacoli (STCC),Pseudomonas aeruginosa(ATCC) and Bacillus cereus(ATCC). The strains, E. coli, S. aureus, P. aeruginosa and B. cereus were susceptible to 50 µg chitosan-decorated bacitracin cream, showing inhibition zones of 10 ± 0.6, 34 ± 1.5, 31 ± 0.76 and 21 ± 2.02 mm, respectively. The zones of inhibition for simple bacitracin-loaded cream were significantly smaller than chitosan-decorated cream, at 2 ± 0.2, 28 ± 0.92, 15 ± 0.5 and 11 ± 1.25 mm (ANOVA; p < 0.05), respectively. (4) Conclusion: It was observed that the zones of inhibition of simple bacitracin-loaded cream were significantly smaller than those of chitosan-decorated bacitracin-loaded cream. Chitosan synergistically improves the antimicrobial activity of bacitracin. Hence, the developed formulation was effective and should be considered as a suitable candidate for topical management of skin infections and wound healing.

Formulation and Evaluation of Chitosan-Gelatin Thermosensitive Hydrogels Containing 5FU-Alginate Nanoparticles for Skin Delivery.

(1) Background: Chitosan-gelatin-based thermosensitive hydrogel containing 5FU-alginate nanoparticles was formulated for the effective and sustained delivery of 5FU to the skin. (2) Methods: Alginate, a polysaccharide was used for the formulation of nanoparticles using a spray drying technique. Size, zeta potential, and surface morphology were investigated using a zetasizer and scanning electron microscope. The hydrogel was fabricated using chitosan and gelatin. Several important analyses were used to characterize these prepared topical hydrogels. The pH, visual transparency, rheological behavior, and swelling index of the prepared hydrogels were evaluated. The in vitro release studies were performed at different pH (5.5 and 7.4) and temperature (32 and 37 °C) conditions using a Franz diffusion cell. Ex vivo permeation and in vivo studies were performed using Sprague Dawley rats. (3) Results: Results show that spherical nanoparticles were produced at sizes of 202−254 nm and with zeta potentials of −43 to −38 mV. The prepared nanoparticles were successfully incorporated into chitosan-gelatin-based hydrogels using a glycerol 2-phosphate disodium salt hydrates crosslinker. Drug polymers and excipients compatibility and formulation of hydrogels was confirmed by ATR-FTIR results. The pH of the prepared hydrogels was in accordance with the skin pH. The viscosity of prepared hydrogel increased with temperature increase and phase transition (sol-gel transition) occurred at 34 °C. The release of drug was sustained in case of nanoparticles incorporated hydrogels (5FU-Alg-Np-HG) as compared to nanoparticles (5FU-Alg-Np) and simple hydrogels (5FU-HG) (ANOVA; p < 0.05). The premature and initial burst release of 5FU was prevented using 5FU-Alg-Np-HG. The release mechanism of 5FU from the 5FU-Alg-Np-HG diffusion was followed by swelling and erosion, as suggested by Korsmeyer-Peppas model. The prepared hydrogel proved to be non-irritant. Ex vivo permeation study across rat's skin suggests that permeability of nanoparticles (5FU-Alg-Np) was higher than the 5FU-Alg-Np-HG (ANOVA; p < 0.05). However, skin-related drug retention of 5FU-Alg-Np-HG was significantly higher than the 5FU solution, 5FU-Alg-Np, and 5FU-HG (ANOVA; p < 0.05). This was due to swelling of hydrogels in the lower layers of skin where the temperature is 37 °C. The higher concentration of 5FU in the skin is helpful for treatment of local skin cancer, such as melanoma, and actinic keratosis. In vivo results also confirmed maximum AUC, t1/2, and skin-related drug retention of 5FU-Alg-Np-HG. (4) Conclusions: Chitosan-gelatin-based hydrogels containing 5FU-Alg-Np possess exceptional properties, and can be used for the sustained delivery of 5FU for the treatment of local skin cancers.

Synthesis and Characterization of Chitosan-Decorated Nanoemulsion Gel of 5-Fluorouracil for Topical Delivery.

(1) Background: The present study aimed to prepare chitosan-coated nanoemulsion gel containing 5-fluorouracil for enhanced topical delivery. (2) Methods: To formulate the nanoemulsion gel, oleic acid was used as the oil phase and Carbopol 940 as a gelling agent. Chitosan was used as a coating agent to control the release of 5-FU. Drug−excipient compatibility was evaluated using ATR-FTIR. The prepared nanoemulsion formulations were characterized based on particle size distribution, zeta potential, % encapsulation efficiency and drug content. In vitro drug release, skin drug retention and ex vivo permeation profiles were performed across rat skin using a Franz diffusion cell. Skin irritation experiments were also conducted on rats to examine the irritation potential of the formulations. (3) Results: It was found that the drug and excipients were compatible and chitosan successfully coated 5-FU, as demonstrated by ATR-FTIR results. The introduction of chitosan increased the size and zeta potential of the nanoemulsion. The 5-FU release in vitro was significantly lowered in the case of chitosan-decorated nanoemulsion (5-FU-C-NE), whereas the permeation and skin drug retention were higher in the case of 5-FU-C-NE. The formulations were proven non-irritant to the skin of the rats. The optimized formulation of the nanoemulsion was introduced into 1% Carbopol 940 gel. Incorporating the nanoemulsion into the gel further reduced the drug release in vitro and ex vivo permeation, whereas the retention of the drug in the skin was significantly increased (ANOVA; p < 0.05). The increase in skin retention was due to the presence of chitosan and Carbopol 940. The in vitro and ex vivo results were also confirmed with in vivo studies. Incorporating nanoemulsion into gel has resulted in higher Tmax, longer half-life and greater skin drug retention. (4) Conclusion: The results suggest that chitosan-decorated nanoemulsion gel is safe and can potentially be used to promote 5-FU skin retention, which is ideal for skin diseases such as melanoma.

A Low-Cost Device for Measurement of Exhaled Breath for the Detection of Obstructive Lung Disease.

Breath sensor technology can be used in medical diagnostics. This study aimed to build a device to measure the level of hydrogen sulfide, ammonia, acetone and alcohol in exhaled breath of patients as well as healthy individuals. The purpose was to determine the efficacy of these gases for detection of obstructive lung disease. This study was conducted on a total of 105 subjects, where 60 subjects were patients of obstructive lung disease and 45 subjects were healthy individuals. Patients were screened by means of the Pulmonary Function Test (PFT) by a pulmonologist. The gases present in the exhaled breath of all subjects were measured. The level of ammonia (32.29 ± 20.83 ppb), (68.83 ± 35.25 ppb), hydrogen sulfide (0.50 ± 0.26 ppm), (62.71 ± 22.20 ppb), and acetone (103.49 ± 35.01 ppb), (0.66 ± 0.31 ppm) in exhaled breath were significantly different (p < 0.05) between obstructive lung disease patients and healthy individuals, except alcohol, with a p-value greater than 0.05. Positive correlation was found between ammonia w.r.t Forced Expiratory Volume in 1 s (FEV1) (r = 0.74), Forced Vital Capacity (FVC) (r = 0.61) and Forced Expiratory Flow (FEF) (r = 0.63) and hydrogen sulfide w.r.t FEV1 (r = 0.54), FVC (r = 0.41) and FEF (r = 0.37). Whereas, weak correlation was found for acetone and alcohol w.r.t FEV1, FVC and PEF. Therefore, the level of ammonia and hydrogen sulfide are useful breath markers for detection of obstructive lung disease.