Review of corrosive environments for copper and its corrosion inhibitors

This review paper deals with corrosion of copper and its alloys in corrosive environments and their corrosion inhibitors. The main corrosion inhibitor groups for copper are introduced and a review of adsorption models is provided. The main part of this work is to investigate different corrosive environments for copper and its alloys and their corrosion inhibitors used in such environments to protect copper. According to the literature, the corrosion inhibition behavior of organic corrosion inhibitors and their derivatives in comparison with inorganic ones are further evaluated. Knowing maximum corrosion inhibition efficiency of a specific corrosion inhibitor in a specific corrosive environment is helpful to choose the most appropriate corrosion inhibitor compound.     

二茂铁及其衍生物在传感器上的应用进展

二茂铁是一类具有夹心结构的有机金属配合物,有良好的氧化 还原特性,可有效改善传感器电极上的电子传递效率。 本文评述了近年来二茂铁及其衍生物在酶生物传感器、免疫传感器和离子传感器上的研究状况,并对其今后的发展方向做出展望。     

Application of nanomaterials in microbial-cell biosensor constructions

Microbial cell biosensors, where cells are in direct connection with a transducer enabling quantitative and qualitative detection of an analyte, are very promising analytical tools applied mainly for assays in the environmental field, food industry or biomedicine. Microbial cell biosensors are an excellent alternative to conventional analytical methods due to their specificity, rapid detection and low cost of analysis. Nowadays, nanomaterials are often used in the construction of biosensors to improve their sensitivity and stability. In this review, the combination of microbial and other individual cells with different nanomaterials (carbon nanotubes, graphene, gold nanoparticles, etc.) for the construction of biosensors is described and their applications are provided as well.     

Affinity and enzyme-based biosensors: recent advances and emerging applications in cell analysis and point-of-care testing

The applications of biosensors range from environmental testing and biowarfare agent detection to clinical testing and cell analysis. In recent years, biosensors have become increasingly prevalent in clinical testing and point-of-care testing. This is driven in part by the desire to decrease the cost of health care, to shift some of the analytical tests from centralized facilities to "frontline" physicians and nurses, and to obtain more precise information more quickly about the health status of a patient. This article gives an overview of recent advances in the field of biosensors, focusing on biosensors based on enzymes, aptamers, antibodies, and phages. In addition, this article attempts to describe efforts to apply these biosensors to clinical testing and cell analysis.     

Multifunctional micro-/nanoscaled structures based on polyaniline: an overview of modern emerging devices

With the advent of Materials Science-based technological advances, the fabrication of materials that could simultaneously exhibit both mechanical and processing properties of polymers and unique electrical characteristics of metals is a requirement with prior mandate. With the development of conducting polymers, great opportunities have been established, and novel devices with the significant features have emerged. Polyaniline (PANI) and its derivatives have attracted immense attention because of their fascinating properties, including high conductivity, inexpensiveness of starting material, unique redox behavior, facile synthesis, tunable properties, appropriate electrochemical and environmental stability, and strong bimolecular interactions. Nanostructures based on PANI have shown improved functionalities in various applications. In this article, different synthesis strategies such as interfacial polymerization, microwave-assisted polymerization, and sonochemical polymerization among others have been summarized. Besides, PANI-based nanocomposites and their various industrial, as well as biomedical applications in supercapacitors, batteries, gas vapor sensors, printable electronics, electrochromics, actuators, electrostatic dissipation, electromagnetic interference shielding, corrosion protection, filtration membranes, microbial fuel cell, biosensors, tissue engineering, and drug delivery systems, have been discussed in detail.     

Monte Carlo simulations of corrosion inhibition of mild steel in 0.5 M sulphuric acid by some green corrosion inhibitors

Atomistic modelling and simulations are becoming increasingly important in the field of corrosion inhibition. New research and development efforts and new possibilities for using computational chemistry in studying the behaviour of corrosion inhibitors on the metal surfaces are introduced. In this study, Monte Carlo simulations technique incorporating molecular mechanics and molecular dynamics were used to simulate the adsorption of methionine derivatives, namely l-methionine, l-methionine sulphoxide and l-methionine sulphone, on iron (110) surface in 0.5 M sulphuric acid. Adsorption energy as well as hydrogen bond length has been calculated. Results show that methionine derivatives have a very good inhibitive effect for corrosion of mild steel in 0.5 M sulphuric acid solution. Tafel polarisation studies have shown that methionine derivatives act as mixed-type inhibitors, and their inhibition mechanism is adsorption assisted by hydrogen bond formation. Impedance results indicate that the values of the constant phase element tend to decrease with increasing methionine derivatives concentrations due to the increase in the thickness of the electrical double layer. In addition, both polarisation resistance and inhibition efficiency E _i(%) tend to increase with increasing inhibitors concentrations due to the increase of the surface coverage, i.e., the decrease of the electrochemical active surface area. The quantum mechanical approach may well be able to foretell molecular structures that are better for corrosion inhibition.     

Semi-Synthesis of Small Molecules of Aminocarbazoles: Tumor Growth Inhibition and Potential Impact on p53

The tumor suppressor p53 is inactivated by mutation in approximately 50% of human cancers. Small molecules that bind and stabilize those mutants may represent effective anticancer drugs. Herein, we report the tumor cell growth inhibitory activity of carbazole alkaloids and amino derivatives, as well as their potential activation of p53. Twelve aminocarbazole alkaloids were semi-synthesized from heptaphylline (1), 7-methoxy heptaphylline (2), and 7-methoxymukonal (3), isolated from Clausena harmandiana, using a reductive amination protocol. Naturally-occurring carbazoles 1–3 and their amino derivatives were evaluated for their potential effect on wild-type and mutant p53 activity using a yeast screening assay and on human tumor cell lines. Naturally-occurring carbazoles 1–3 showed the most potent growth inhibitory effects on wild-type p53-expressing cells, being heptaphylline (1) the most promising in all the investigated cell lines. However, compound 1 also showed growth inhibition against non-tumor cells. Conversely, semi-synthetic aminocarbazole 1d showed an interesting growth inhibitory activity in tumor cells expressing both wild-type and mutant p53, exhibiting low growth inhibition on non-tumor cells. The yeast assay showed a potential reactivation of mutant p53 by heptaphylline derivatives, including compound 1d. The results obtained indicate that carbazole alkaloids may represent a promising starting point to search for new mutp53-reactivating agents with promising applications in cancer therapy.     

Advances in the Chemistry of 2,4,6-Tri(thiophen-2-yl)-1,3,5-triazine

Heterocyclic systems are now considered to be an integral part of material chemistry. Thiophene, selenophene, furan, pyrrole, carbazole, triazine and others are some such examples worth mentioning. 2,4,6-Tri(thiophen-2-yl)-1,3,5-triazine is a C_3h-symmetric system with thiophene as the donor unit and s-triazine as the acceptor unit. This review gives an insight into the advances made in the thienyl-triazine chemistry over the past two to three decades. The synthetic pathways for arriving at this system and all its important derivatives are provided. The major focus is on the materials synthesized using the thienyl-triazine system, including star molecules, linear and hyperbranched polymers, porous materials and their diverse applications. This review will play a catalytic role for new dimensions to be explored in thienyl-triazine chemistry.     

Review on recent development of quinoline for anticancer activities

Quinoline is an efficient scaffold for anticancer drug development as its derivatives have shown potent results through several mechanisms like growth regulators through “apoptosis, disruption of cell migration, inhibition of angiogenesis, modulation of nuclear receptor responsiveness and cell cycle arrest, etc.,” The potential of quinoline derivatives has been proved in several cancer cell lines like breast cancer, colon cancer, lung cancer, colorectal cancer, renal cancer, etc. This review article aims to provide information about the synthesis, potential of the anticancer property, cytotoxicity, and level of clinical treatments, which could lay out the research to develop more effective quinoline-derived anticancer drugs.     

Amino acids and their derivatives as corrosion inhibitors for metals and alloys

In the last two decades, research in the field of corrosion inhibitors had been directed toward the goal of using cheap effective molecules of low or non-negative environmental impact to replace the environmentally hazardous compounds. One of the encourager compounds which can be used as safe corrosion inhibitors are amino acids. They are environmentally friendly, non-toxic, biodegradable and relatively cheap. On other hand, the development of computational modeling helps to understand the inhibition mechanism of those compounds and to develop the newly designed inhibitors. In this review, most of contribution made in literature on the use of amino acids and their derivatives as corrosion inhibitors for metallic alloys materials were presented and discussed.     

Biosensors containing acetylcholinesterase and butyrylcholinesterase as recognition tools for detection of various compounds

Acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) are enzymes expressed in the human body under physiological conditions. AChE is an important part of the cholinergic nerves where it hydrolyses neurotransmitter acetylcholine. Both cholinesterases are sensitive to inhibitors acting as neurotoxic compounds. In analytical applications, the enzymes can serve as a biorecognition element in biosensors as well as simple disposable sensors (dipsticks) and be used for assaying the neurotoxic compounds. In the present review, the mechanism of AChE and BChE inhibition by disparate compounds is explained and methods for assaying the enzymes activity are shown. Optical, electrochemical, and piezoelectric biosensors are described. Attention is also given to the application of sol-gel techniques and quantum dots in the biosensors’ construction. Examples of the biosensors are provided and the pros and cons are discussed.     

Plant extracts as “green” corrosion inhibitors for steel in sulphuric acid

In recent years, plant extracts have become the focus of corrosion inhibitor research due to their low toxicity, easy availability and economical preparation. This review presents most of the recent contributions made to the application of plant extracts as corrosion inhibitors for steel in sulphuric acid, as well as in both hydrochloric acid and sulphuric acid. The constituents, properties, adsorption modes and inhibition mechanisms of these natural products are discussed. Evaluation methods and the factors that influence the corrosion-inhibition efficiency of plant extracts are also summarised.     

Biosensing Membrane Base on Ferulic Acid and Glucose Oxidase for an Amperometric Glucose Biosensor

A biosensing membrane base on ferulic acid and glucose oxidase is synthesized onto a carbon paste electrode by electropolymerization via cyclic voltammetry in aqueous media at neutral pH at a single step. The developed biosensors exhibit a linear response from 0.082 to 34 mM glucose concentration, with a coefficient of determination R² equal to 0.997. The biosensors display a sensitivity of 1.1 μAmM⁻¹ cm⁻², a detection limit of 0.025 mM, and 0.082 mM as glucose quantification limit. The studies reveal stable, repeatable, and reproducible biosensors response. The results indicate that the novel poly-ferulic acid membrane synthesized by electropolymerization is a promising method for glucose oxidase immobilization towards the development of glucose biosensors. The developed glucose biosensors exhibit a broader linear glucose response than other polymer-based glucose biosensors.     

A Brief Review on Fruit and Vegetable Extracts as Corrosion Inhibitors in Acidic Environments

The corrosion of metals, i.e., the initiation and acceleration of the surface deterioration of metals through an electrochemical reaction with the surrounding intrusive environment, is a global concern because of the economic and environmental impacts. Corrosion inhibitors are considered the most practical choice among the available corrosion protection techniques due to their effectiveness in terms of functionality and cost. The use of traditional and toxic corrosion inhibitors has led to environmental issues, arousing the need for green counterparts that are environmentally friendly, easily accessible, biodegradable, and cost-effective. In this review, the utilization of green corrosion inhibitors purely acquired from renewable sources is explored, with an in-depth focus on the recent advancements in the use of fruit and vegetable extracts as green corrosion inhibitors. In particular, fruits and vegetables are natural sources of various phytochemicals that exhibit key potential in corrosion inhibition. To shed light on the true potential of such extracts in the protection of steel in acidic environments, the experimental techniques involved in corrosion inhibition and the mechanism of corrosion inhibition are discussed in detail. The study highlights the potential of fruit and vegetable extracts as non-toxic, economical, and effective corrosion inhibitors in the pursuit of green chemistry. In addition to discussing and outlining the current status and opportunities for employing fruit and vegetable extracts as corrosion inhibitors, the current review outlines the challenges involved in the utilization of such extracts in corrosion inhibition.     

Thin Films and Composites Based on Graphene for Electrochemical Detection of Biologically‐relevant Molecules

Graphene is one of the most studied materials ever, owing to its exceptional electronic, mechanical and thermal properties, which allow for many different types of application. In this review, we shall concentrate on the use of graphene and derivatives for electrochemical sensors and biosensors, where emphasis is placed on the importance of surface functionalization as this permits synergistic combinations with other nanomaterials and biomolecules. In addition to describing recent advances in graphene‐based electroanalytical applications, we discuss a few examples of their use in detecting small biomolecules and in immunosensing for a few diseases using films and composites. Also discussed are the possible methods for mass production of graphene, which is key to low‐cost biosensors for implantable devices and portable systems in point‐of‐care diagnosis.     

Recent Progress in the Development of Conducting Polymer‐Based Nanocomposites for Electrochemical Biosensors Applications: A Mini‐Review

Among various immobilizing materials, conductive polymer‐based nanocomposites have been widely applied to fabricate the biosensors, because of their outstanding properties such as excellent electrocatalytic activity, high conductivity, and strong adsorptive ability compared to conventional conductive polymers. Electrochemical biosensors have played a significant role in delivering the diagnostic information and therapy monitoring in a rapid, simple, and low cost portable device. This paper reviews the recent developments in conductive polymer‐based nanocomposites and their applications in electrochemical biosensors. The article starts with a general and concise comparison between the properties of conducting polymers and conducting polymer nanocomposites. Next, the current applications of conductive polymer‐based nanocomposites of some important conducting polymers such as PANI, PPy, and PEDOT in enzymatic and nonenzymatic electrochemical biosensors are overviewed. This review article covers an 8‐year period beginning in 2010.     

Luminol-Based Chemiluminescent Signals: Clinical and Non-clinical Application and Future Uses

Chemiluminescence (CL) is an important method for quantification and analysis of various macromolecules. A wide range of CL agents such as luminol, hydrogen peroxide, fluorescein, dioxetanes and derivatives of oxalate, and acridinium dyes are used according to their biological specificity and utility. This review describes the application of luminol chemiluminescence (LCL) in forensic, biomedical, and clinical sciences. LCL is a very useful detection method due to its selectivity, simplicity, low cost, and high sensitivity. LCL has a dynamic range of applications, including quantification and detection of macro and micromolecules such as proteins, carbohydrates, DNA, and RNA. Luminol-based methods are used in environmental monitoring as biosensors, in the pharmaceutical industry for cellular localization and as biological tracers, and in reporter gene-based assays and several other immunoassays. Here, we also provide information about different compounds that may enhance or inhibit the LCL along with the effect of pH and concentration on LCL. This review covers most of the significant information related to the applications of luminol in different fields.     

Enantioselective recognition based on aggregation-induced emission

Chirality is one of the most important features of the nature. The recognition of enantiomers plays significant roles in the field of life science, pharmaceutical analysis and food chemistry. Among various recognition methods, fluorescence spectrometry has attracted much attention of researchers thanks to its high sensitivity and easy operation. Compared with traditional fluorescent probes, chiral molecules with aggregation-induced emission (AIE) have drawn increasing interests due to their huge potential in high-efficiency chemo/biosensors and solid emitters. Chiral AIE luminogens (AIEgens) can not only discriminate two enantiomers with excellent enantioselectivity, but also show general applicability for many chiral analytes, such as chiral acids, amino acids, amines, alcohols. In this review, we mainly summarized the recent development of chiral probes with AIE properties, including chiral tetraphenylethylene (TPE) derivatives, α-cyanostilbene derivatives, Schiff base derivatives and other AIEgens. Their synthetic routes, recognition capabilities and possible working mechanisms were well discussed. It is envisioned that the present review can give some significant guidance for design and synthesis of chiral AIEgens with good enantioselectivity and inspire more readers to join the research of chiral AIE.