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In the last decades, corrosion control of metals and their alloys has been of environmental, aesthetic, economic, and technical importance. Ecologically acceptable, environment-friendly, and readily available corrosion inhibitors are one of the best options for protecting metals against corrosion. In this regard, use of polymers for inhibiting metallic corrosion is an authentic and acceptable practice, with a low environmental threat. Polymers may be used as composites, blends, or isolation for optimal inhibitory effects. Inhibition efficiencies of corrosion inhibitors were determined using mass loss, electrochemical impedance spectroscopy, potentiodynamic polarization techniques, etc. The present study gives the idea about natural, synthetic, and conducting polymers and their utilization for corrosion inhibition applications. Effects of halide ions as additives or surfactants on their anticorrosion performances are also discussed. Polymeric materials as coatings are reviewed to align with recent research interests, such as cost-effectiveness, environment friendliness, and self-healing products, which are more convenient to synthesize and use in future applications.

Herein, we reported the dual functions of molybdenum disulfide/sulfur-doped graphitic carbon nitride (MoS2/SGCN) composite as a sensing material for electrochemical detection of 4-NP and a catalyst for 4-NP degradation. The MoS2 nanosheet, sulfur-doped graphitic carbon nitride (SGCN) and MoS2/SGCN were characterized using field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD) spectroscopy and X-ray photoelectron spectroscopy (XPS). Electrochemical characterization of these materials with electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) in 1 mM K4[Fe(CN)6]3-/4- show that the composite has the lowest charge transfer resistance and the best electrocatalytic activity. The limit of detection (LOD) and the linear range of 4-nitrophenol at MoS2/SGCN modified glassy carbon electrode (MoS2/SGCN/GCE) were computed as 12.8 nM and 0.1 – 2.6 μM, respectively. Also, the percentage recoveries of 4-NP in spiked tap water samples ranged from 97.8 – 99.1 %. The electroanalysis of 4-NP in the presence of notable interferons shows that the proposed electrochemical sensor features outstanding selectivity toward 4-NP. Additionally, the results of the catalytic degradation of 4-NP at MoS2/SGCN show that the nanocatalyst catalyzed the transformation of 4-NP to 4-aminophenol (4-AP) with a first-order rate constant (k) estimated to be 4.2 ×10−2 s−1. The results of this study confirm that the MoS2/SGCN nanocatalyst is a useful implement for electroanalytical monitoring and catalytic degradation of the hazardous 4-NP in water samples.

A corrosion inhibition test, coupled with a quantification of in-situ H2 evolution, can be used to evaluate an organic inhibitor such as Timoho leaf extract (TLE). TLE is a biodegradable and effective corrosion inhibitor because of its potential to protect 304SS against sulfuric acid. TLE corrosion inhibitor was studied through systematic electrochemical experiments and morphological characterization, with a concentration range of 0–6g L−1. Convolutional Neural Network (CNN)-VGG16 was one of the machine learning approaches used to classify and predict physical changes in hydrogen gas bubbles. Constituents of the TLE and 304SS surfaces were analyzed by FT-IR and UV–Vis tests. The results suggested that 3 g L−1 TLE inhibitor was able to reduce the corrosion rate by 99.37 %. The TLE's inhibition mechanism on 304SS was mixed adsorption and mixed type inhibitor that followed the Isothermal Freundlich Equation. The prediction model by CNN-VGG16 for corrosion tests at varied inhibitor doses was 96% accurate. SEM tests revealed that TLE constituent adsorption on the 304SS surface had a smooth surface morphology with few degraded spots.

Abstract Photoactive supramolecular porphyrin assemblies are attractive molecules for light‐harvesting applications. This is due to their relatively non‐toxicity, biological activities and charge and energy exchange characteristics. However, the extreme cost associated with their synthesis and requirements for toxic organic solvents during purification pose a challenge to the sustainability characteristics of their applications. This work presents the first report on the sustainable synthesis, spectroscopic and photophysical characterizations of a near‐infrared (NIR) absorbing Ca(II)‐meso‐tetrakis (4‐hydroxyphenyl)porphyrin using an electrolyzed pyrrole solution. The latter was obtained by cycling the pyrrole solution across the silver nanodumbbell particle surface at room temperature. The electrolyzed solution condensed readily with acidified p‐hydroxybenzaldehyde, producing the targeted purple porphyrin. The non‐electrolyzed pyrrole solution formed a green substance with significantly different optical properties. Remarkable differences were observed in the voltammograms of the silver nanodumbbell particles and those of the conventional gold electrode during the pyrrole cycling, suggesting different routes of porphyrin formation. The rationale behind these formations and the associated mechanisms were extensively discussed. Metalation with aqueous Ca2+ ion caused a Stokes shift of 38.75 eV. The current study shows the advantage of the electrochemical method towards obtaining sustainable light‐harvesting porphyrin at room temperature without the need for high‐energy‐dependent conventional processes.

Abstract Monoamine neurotransmitters are essential for learning, mental alertness, emotions, and blood flow, among other functions. Fatal neurological disorders that signal the imbalance of these biomolecules in the human system include Parkinson's disease, myocardial infarction, Alzheimer's disease, hypoglycemia, Schizophrenia, and a host of other ailments. The diagnosis of these monoamine neurotransmitter‐related conditions revolves around the development of analytical tools with high sensitivity for the four major monoamine neurotransmitters namely dopamine, epinephrine, norepinephrine, and serotonin. The application of electrochemical sensors made from notable metal oxide nanoparticles or composites containing the metal oxide nanoparticles for the detection of these monoamine neurotransmitters was discussed herein. More importantly, the feasibility of the application of the ZnO, CuO, and TiO2 nanoparticle‐based electrochemical sensors for a comprehensive diagnosis of monoamine neurotransmitter‐related conditions was critically investigated in this review.

Abstract In this study, a novel electrodeposition of poly(2,4,6‐trihydroxybenzaldehyde) on bare glassy carbon electrode for dopamine detection was reported. 2,4,6‐trihydroxybenzaldehyde and the electrodeposited poly(2,4,6‐trihydroxybenzaldehyde) were characterized using Fourier transform‐infrared spectroscopy, UV‐visible spectroscopy, and scanning electron microscopy. The bare electrode modified with the optimum amount of 2,4,6‐trihydroxybenzaldehyde (PTGCE) was used for dopamine electroanalysis. The linear dynamic range and the limit of detection of DA at PTGCE were 0.70‐19.48 μM and 19.48–53.30 μM, and 0.64 μM, respectively. The modified electrode showed outstanding discriminatory dopamine detection in the presence of uric acid and ascorbic acid due to a dopamine‐uric acid and a dopamine‐ascorbic acid peak‐to‐peak separation of 160 mV and 200 mV, respectively. The proposed sensor showed considerable reproducibility of dopamine current response and excellent % dopamine recovery of 99.70 % from the real sample solution.

Abstract Background The low demand for maternal and child health services is a significant factor in Nigeria's high maternal death rate. This paper explores demand and supply-side determinants at the primary healthcare level, highlighting factors affecting provision and utilization. Methods This qualitative study was undertaken in Anambra state, southeast Nigeria. Anambra state was purposively chosen because a maternal and child health programme had just been implemented in the state. The three-delay model was used to analyze supply and demand factors that affect MCH services and improve access to care for pregnant women/mothers and newborns/infants. Result The findings show that there were problems with both the demand and supply aspects of the programme and both were interlinked. For service users, their delays were connected to the constraints on the supply side. On the demand side, the delays include poor conditions of the facilities, the roads to the facilities are inaccessible, and equipment were lacking in the facilities. These delayed the utilisation of facilities. On the supply side, the delays include the absence of security (fence, security guard), poor citing of the facilities, inadequate accommodation, no emergency transport for referrals, and lack of trained staff to man equipment. These delayed the provision of services. Conclusion Our findings show that there were problems with both the demand and supply aspects of the programme, and both were interlinked. For service users, their delays were connected to the constraints on the supply side.

Abstract Anticorrosion and adsorption behaviour of synthesized carbohydrazide Schiff bases, namely (Z)-N′-(4-hydroxy-3-methoxybenzylidene)-6-methyl-2-oxo-4-phenyl-1,2,3,4-tetrahydropyrimidine-5-carbohydrazide(MBTC) and (Z)-N′-(3,4-dichlorobenzylidene)-6-methyl-2-oxo-4-phenyl-1,2,3,4-tetrahydropyrimidine-5-carbohydrazide (CBTC) was examined for mild steel (MS) in 15% HCl medium. The corrosion inhibition study was performed by using gravimetric, thermodynamic, electrochemical and theoretical studies including density functional theory (DFT), molecular dynamic simulation (MDS) and Monte Carlo simulations (MCS). The outcomes in terms of corrosion inhibition efficiency using electrochemical impedance spectroscopy (EIS) method at 303 K and 150 ppm concentration were 96.75% for MBTC and 95.14% for CBTC. Both inhibitors adsorbed on the MS surface through physical as well as chemical adsorption and followed the Langmuir isotherm. The mixed-type nature of both inhibitors was identified by polarization results. Surface analysis was done using FESEM, EDX, AFM and XPS studies and results showed that a protective layer of inhibitor molecules was developed over the surface of MS. The results of DFT, MCS and MDS are in accordance with experimental results obtained by weight loss and electrochemical methods.

Probiotics are live microorganisms recognized as natural candidates to substitute antibiotic substances, usually used to treat bacterial infections responsible for numerous human and animal diseases. Antibiotics are mostly prescribed for treating infections caused by bacteria. However, their excessive and inappropriate use has resulted in the increase of bacterial antimicrobial resistance (AMR) and host microbiota imbalance or dysbiosis phenomena. Even though antibiotics are the most well-known lifesaving substances, the AMR within the bacterial community has become a growing threat to global health, with the potential to cause millions of deaths each year in the future. Faced with these worldwide issues, it is high time to discover and develop antibiotic alternatives. There exists some evidence of probiotic roles in antagonizing pathogens, modulating immune systems, and maintaining general host health by restoring the gut microbiota balance. The multi-antimicrobial action mechanisms of such beneficial living microorganisms are one approach to practicing the “prevention is better than cure” concept to avoid antibiotics. The current review proposes a comprehensive description of antibiotic-related AMR issues and the potential of probiotics as antibiotic alternatives, while discussing pros and cons, as well as some evidence of beneficial uses of probiotics for human and animal health protection through recent results of experimental models and clinical trials.

Background: At the moment, there is no vaccine for the hepatitis C virus (HCV), despite it being more infectious than the hepatitis B virus (HBV) and the human immunodeficiency virus (HIV). Existing drugs based on protease and polymerase inhibitors present adverse clinical outcomes, sparking the search for alternatives. Medicinal plants contain bioactive compounds that hold great promise. Thus, the present study was aimed at evaluating the druggability of bioactive compounds implicated in folk medicine in the management of HCV against RNA-directed RNA polymerase (RdRp). Methods: Traditional healers involved in the management of hepatitis were consulted, and they suggested the use of leaves of Vernonia amygdalina, Jatropha tanjorensis, Annona muricata, and Solanum nigrum (berries too) in the management of hepatitis. The collection of plant parts and phytochemical screening via gas chromatography-mass spectrophotometer (GC–MS) were carried out. Resulting bioactive compounds and a control HCV drug, remdesivir, were screened for ADMET properties using the pkCSM online prediction tool, while molecular docking was performed using AutoDockTool 1.5.6 and the resulting interactions visualised in 2-Dimension using Discovery Studio 2022 Client. Results: GC–MS analysis of the medicinal plants revealed 60 bioactive compounds, of which 15 did not violate Lipinski's rule of five and 2 returned only one violation, while the control drug returned two violations. All the ligands were not inhibitors of CYP1A2, CYP2C19, CYPCC9, CYPAD6, and CYP3A4, except for 1,3-dihydrobenzo-[c]thiophen, docosahexaenoic acid, and benzonitrile N-oxide, which were inhibitors of CYP1A2. The intestinal absorption rates of the various ligands (73.56–100 %) were better than those of remdesivir, with an intestinal absorption rate of 67.15 %. Docking analysis revealed scores that ranged from -4.3 to -8.0 k/cal for the ligands, while the score for remdesivir was -9.0 k/cal. Eight ligands and remdesivir interacted with both the finger and palm regions, while one ligand interacted with the finger and thumb regions. Others interacted either with the finger (n = 5) or palm (n = 3) regions. These various interactions have the potential to alter the structural integrity and conformation of the RdRp protein and, in the process, interfere with its role in replication. Conclusion: The findings indicate that the selected medicinal plants possess bioactive compounds that hold great promise for the development of newer and safer nucleoside inhibitors against HCV. Given the high diversity of the virus, there may be a need to expand the scope of genotype-specific treatment regimens using bioactive compounds from medicinal plants. List of Abbreviations and Units: AA, Amino Acid; HCV, Hepatitis C Virus; HBV, Hepatitis B Virus; GC–MS, Gas chromatograph-mass spectrophotometer; MD, Molecular docking; PDB, Protein Data Bank; RdRp, RNA directed RNA polymerase; RNA, Ribonucleic Acid; HIV, Human Immunodeficiency virus; NIST, National Institute of Standards and Technology; WHO, World Health Organization

Sustainable corrosion inhibitors are being developed as many of them are ecologically friendly, biodegradable, and devoid of heavy metals and other potentially dangerous compounds. Albumin, a member of the globular protein family obtained from egg white, has found its application in a variety of various applications due to its intrinsic pharmacological qualities (anti-bacterial, immunomodulating, and anti-cancer angiotensin-converting enzyme inhibition). Herein, Albumin extract containing atoms with lone pairs of electrons such as Nitrogen (N), Oxygen (O) and having an aromatic ring (unsaturation) has been investigated as an eco-friendly inhibitor for low-carbon steel. The present work studied the inhibition action of Albumin extract for low-carbon steel in 1N acidic chloride and sulfate media using gravimetric, and electrochemical methods, viz potentiodynamic polarization (PDP) and AC impedance studies (EIS). The results obtained from PDP and EIS analysis revealed that the inhibitor exhibited anodic inhibition in 1N HCl (92.72%) and mixed-type but predominantly cathodic inhibition in 1N H2SO4 (79.23%). The studied green corrosion inhibitor followed Langmuir monolayer adsorption and the formation of a protective film on a low-carbon steel surface was confirmed with AFM and FT-IR results. Thus, Albumin extract exhibited excellent corrosion resistance on low-carbon steel.