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Food safety is the prime area of concern that builds trust. With the prevailing advancements, it has become facile to ensure safety in almost all aspects. Technology has grown from tedious lab techniques to modern chromatographic techniques and immunoassays, progressed with more precise and rapid sensing through the advent of Biosensors. Biosensors provide an automated technology by presenting superfast, nondestructive and cost-effective detection in food analysis. SPR biosensor is an optical biosensor known for its versatility and has wider applications in food testing and analysis. It has an optical system for excitation and interrogation of surface plasmons, and a biomolecular recognition element to detect and seize the target analyte present in a sample. The optical signal detects the binding analyte, on the recognition element, which results in a change in refractive index at the surface and modifies the surface plasmons' propagation constant. SPR aids in label-free detection of various components such as adulterants, antibiotics, biomolecules, genetically modified foods, pesticides, insecticides, herbicides, microorganisms and microbial toxins in food and assures safety. The distinct advancements of SPR in food analysis have been found and discussed. The review also provides knowledge on the advantages and the key challenges encountered by SPR. [ABSTRACT FROM AUTHOR]

Since their discovery in 2008 by N. Ogoshi and co-authors, pillararenes (PAs) have become popular hosts for molecular recognition and supramolecular chemistry, as well as other practical applications. The most useful property of these fascinating macrocycles is their ability to accommodate reversibly guest molecules of various kinds, including drugs or drug-like molecules, in their highly ordered rigid cavity. The last two features of pillararenes are widely used in various pillararene-based molecular devices and machines, stimuli-responsive supramolecular/host–guest systems, porous/nonporous materials, organic–inorganic hybrid systems, catalysis, and, finally, drug delivery systems. In this review, the most representative and important results on using pillararenes for drug delivery systems for the last decade are presented. [ABSTRACT FROM AUTHOR]

This article provides an overview on the broad topic of biogenic amines (BAs) that are a persistent concern in the context of food quality and safety. They emerge mainly from the decomposition of amino acids in protein-rich food due to enzymes excreted by pathogenic bacteria that infect food under inappropriate storage conditions. While there are food authority regulations on the maximum allowed amounts of, e.g., histamine in fish, sensitive individuals can still suffer from medical conditions triggered by biogenic amines, and mass outbreaks of scombroid poisoning are reported regularly. We review first the classical techniques used for selective BA detection and quantification in analytical laboratories and focus then on sensor-based solutions aiming at on-site BA detection throughout the food chain. There are receptor-free chemosensors for BA detection and a vastly growing range of bio- and biomimetic sensors that employ receptors to enable selective molecular recognition. Regarding the receptors, we address enzymes, antibodies, molecularly imprinted polymers (MIPs), and aptamers as the most recent class of BA receptors. Furthermore, we address the underlying transducer technologies, including optical, electrochemical, mass-sensitive, and thermal-based sensing principles. The review concludes with an assessment on the persistent limitations of BA sensors, a technological forecast, and thoughts on short-term solutions. [ABSTRACT FROM AUTHOR]

Nanotechnology and molecular imprinting both are omnipresent in the modern scientific world. Molecular recognition in the biological systems was mimicked to an extreme extent with its difficulties through molecular imprinting. Solving the problems related to this mimicking was the goal of science and technology. Some challenges like difficulties with the imprinting of protein, poor compatibility with aqueous environments, template leakage, and heterogeneous populations of binding sites in the polymers that contribute to a high level of nonspecific binding sites were addressed with recent advancement in the modern era. These issues were solved later with nano level instrumentations and inventions. Different types of nanomaterials were employed for this research on molecular recognition through MIPs to enhance selectivity, sensitivity and stability to specific systems such as sensors. This review paper attempts to give all the recent advances in molecular imprinting and the potential of nanomaterials in electrochemical sensors. [ABSTRACT FROM AUTHOR]

Sucrose is a primary metabolite in plants, a source of energy, a source of carbon atoms for growth and development, and a regulator of biochemical processes. Most of the traditional analytical chemistry methods for sucrose quantification in plants require sample treatment (with consequent tissue destruction) and complex facilities, that do not allow real-time sucrose quantification at ultra-low concentrations (nM to pM range) under in vivo conditions, limiting our understanding of sucrose roles in plant physiology across different plant tissues and cellular compartments. Some of the above-mentioned problems may be circumvented with the use of bio-compatible ligands for molecular recognition of sucrose. Nevertheless, problems such as the signal-noise ratio, stability, and selectivity are some of the main challenges limiting the use of molecular recognition methods for the in vivo quantification of sucrose. In this review, we provide a critical analysis of the existing analytical chemistry tools, biosensors, and synthetic ligands, for sucrose quantification and discuss the most promising paths to improve upon its limits of detection. Our goal is to highlight the criteria design need for real-time, in vivo, highly sensitive and selective sucrose sensing capabilities to enable further our understanding of living organisms, the development of new plant breeding strategies for increased crop productivity and sustainability, and ultimately to contribute to the overarching need for food security. [ABSTRACT FROM AUTHOR]

Hydrogels are significant hydrophilic materials with 3D polymeric network structures, which have received much attention in recent decades. DNA-based hydrogel materials have been widely used for tissue engineering, biosensors, bioanalysis, and clinical therapy on their excellent stability, bioanalysis, biocompatibility, and programmability. The addition of functional DNA (deoxyribonucleic acid) sequences, such as DNAzymes or aptamers, are embedded in polymer networks, which expand the additional molecular recognition capabilities and sensibility of smart DNA hydrogels. In particular, targeting-responsive DNA hydrogels have attracted much attention and provided a portable, sensitive, selective, and visualised detection platform for biosensors. In this review, the latest applications of distinct types of DNA hydrogel biosensors for detection in various fields are introduced. Then, the prospects for future development trends and challenges of DNA-based hydrogel materials for biosensing are given. [ABSTRACT FROM AUTHOR]

Supramolecular polymers are widely utilized and applied in self-assembly or self-healing materials, which can be repaired when damaged. Normally, the healing process is classified into two types, including extrinsic and intrinsic self-healable materials. Therefore, the aim of this work is to review the intrinsic self-healing strategy based on supramolecular interaction or non-covalent interaction and molecular recognition to obtain the improvement of mechanical properties. In this review, we introduce the main background of non-covalent interaction, which consists of the metal–ligand coordination, hydrogen bonding, π–π interaction, electrostatic interaction, dipole–dipole interaction, and host–guest interactions, respectively. From the perspective of mechanical properties, these interactions act as transient crosslinking points to both prevent and repair the broken polymer chains. For material utilization in terms of self-healing products, this knowledge can be applied and developed to increase the lifetime of the products, causing rapid healing and reducing accidents and maintenance costs. Therefore, the self-healing materials using supramolecular polymers or non-covalent interaction provides a novel strategy to enhance the mechanical properties of materials causing the extended cycling lifetime of products before replacement with a new one. [ABSTRACT FROM AUTHOR]

Targeting microtubules (MTs), dynamic and stable proteins in cells, by different ligands have been reported to be a potential strategy to combat cancer cells. Inorganic nanoparticles (NPs) have been widely used as anticancer, antibacterial and free radical scavenging agents, where they come in contact with biological macromolecules. The interaction between the NPs and biological macromolecules like MTs frequently occurs through different mechanisms. A prerequisite for a detailed exploration of MT structures and functions for biomedical applications like cancer therapy is to investigate profoundly the mechanisms involved in MT–NP interactions, for which the full explanation and characterization of the parameters that are responsible for the formation of a NP-protein complex are crucial. Therefore, in view of the fact that the goal of the rational NP-based future drug design and new therapies is to rely on the information of the structural details and protein–NPs binding mechanisms to manipulate the process of developing new potential drugs, a comprehensive investigation of the essence of the molecular recognition/interaction is also of considerable importance. In the present review, first, the microtubule (MT) structure and its binding sites upon interaction with MT stabilizing agents (MSAs) and MT destabilizing agents (MDAs) are introduced and rationalized. Next, MT targeting in cancer therapy and interaction of NPs with MTs are discussed. Furthermore, interaction of NPs with proteins and the manipulation of protein corona (PC), experimental techniques and direct interaction of NPs with MTs, are discussed, and finally the challenges and future perspective of the field are introduced. We envision this review can provide useful information on the manipulation of the MT lattice for the progress of cancer nanomedicine. [ABSTRACT FROM AUTHOR]

ClpXP is an archetypical AAA+ protease, consisting of ClpX and ClpP. ClpX is an ATP-dependent protein unfoldase and polypeptide translocase, whereas ClpP is a self-compartmentalized peptidase. ClpXP is currently the only AAA+ protease for which high-resolution structures exist, the molecular basis of recognition for a protein substrate is understood, extensive biochemical and genetic analysis have been performed, and single-molecule optical trapping has allowed direct visualization of the kinetics of substrate unfolding and translocation. In this review, we discuss our current understanding of ClpXP structure and function, evaluate competing sequential and probabilistic mechanisms of ATP hydrolysis, and highlight open questions for future exploration. [ABSTRACT FROM AUTHOR]

The selective detection of glutathione (GSH) in vitro and in vivo has attracted great attentions, credited to its important role in life activities and association with a series of diseases. Among all kinds of analytical techniques, the fluorescent probe for GSH detection become prevalent recently because of its ease of operation, high temporal-spatial resolution, visualization and noninvasiveness, etc. The special structural features of GSH, such as the nucleophilicity of sulfhydryl group, the concerted reaction ability of amino group, the negative charged nature, the latent hydrogen bonding ability along with its flexible molecular chain, are all potent factors to be employed to design the specific fluorescent probe for GSH and discriminate it from other bio-species including its analogues cysteine (Cys) and homocysteine (Hcy). This paper reviewed the studies in the last 3 years and was organized based on the reaction mechanism of each probe. According to the reactivity of GSH, various recognition mechanisms including Michael addition, nucleophilic aromatic substitution, ordinary nucleophilic substitution, multi-site reaction, and other unique reactions have been utilized to construct the GSH specific fluorescent probes, and the molecular design strategy, photophysical property, recognition mechanism, and bioimaging application of each reported probe were all discussed here systematically. Great progress has been made in this area, and we believe the analyses and summarization of these excellent studies would provide valuable message and inspiration to researchers to advance the research toward clinic applications. [ABSTRACT FROM AUTHOR]

Recognition of cell-surface receptors and co-receptors is a crucial molecular event towards the establishment of HIV infection. HIV exists as several variants that differentially recognize the principal co-receptors, CCR5 and CXCR4, in different cell types, known as HIV co-receptor-tropism. The relative levels of these variants dynamically adjust to the changing host selection pressures to infect a vast repertoire of cells in a stage-specific manner. HIV infection sets in through immune cells such as dendritic cells, macrophages, and T-lymphocytes in the acute stage, while a wide range of other cells, including astrocytes, glial cells, B-lymphocytes, and epithelial cells, are infected during chronic stages. A change in tropism occurs during the transition from acute to a chronic phase, termed as co-receptor switching marked by a change in disease severity. The cellular and molecular events leading to co-receptor switching are poorly understood. This review aims to collate our present understanding of the dynamics of HIV co-receptor-tropism vis-à-vis host and viral factors, highlighting the cellular and molecular events involved therein. We present the possible correlations between virus entry, cell tropism, and co-receptor switching, speculating its consequences on disease progression, and proposing new scientific pursuits to help in an in-depth understanding of HIV biology. [ABSTRACT FROM AUTHOR]

Biofabrication by three-dimensional (3D) printing has been an attractive technology in harnessing the possibility to print anatomical shaped native tissues with controlled architecture and resolution. 3D printing offers the possibility to reproduce complex microarchitecture of native tissues by printing live cells in a layer by layer deposition to provide a biomimetic structural environment for tissue formation and host tissue integration. Plant based biomaterials derived from green and sustainable sources have represented to emulate native physicochemical and biological cues in order to direct specific cellular response and formation of new tissues through biomolecular recognition patterns. This comprehensive review aims to analyze and identify the most commonly used plant based bioinks for 3D printing applications. An overview on the role of different plant based biomaterial of terrestrial origin (Starch, Nanocellulose and Pectin) and marine origin (Ulvan, Alginate, Fucoidan, Agarose and Carrageenan) used for 3D printing applications are discussed elaborately. Furthermore, this review will also emphasis in the functional aspects of different 3D printers, appropriate printing material, merits and demerits of numerous plant based bioinks in developing 3D printed tissue-like constructs. Additionally, the underlying potential benefits, limitations and future perspectives of plant based bioinks for tissue engineering (TE) applications are also discussed. • Plant derived bioinks exhibit superior biocompatibility, biodegradability and mechanical stability. • This review provides an outline of diverse plant based bioinks of terrestrial and marine origin for 3D printing applications. • Cellular activity of bioinks is affected by printing parameters and bioink properties. • Nanocellulose and alginate have been in the forefront proving to be potential candidates in 3D bioprinting. [ABSTRACT FROM AUTHOR]

A grand challenge in drug delivery is providing the right dose, at the right anatomic location, for the right duration of time to maximize therapeutic efficacy while minimizing off-target toxicity and other deleterious side-effects. Two general modalities are receiving broad attention for localized drug delivery. In the first, referred to as "targeted accumulation", drugs or drug carriers are engineered to have targeting moieties that promote their accumulation at a specific tissue site from circulation. In the second, referred to as "local anchoring", drugs or drug carriers are inserted directly into the tissue site of interest where they persist for a specified duration of time. This review surveys recent advances in harnessing molecular recognition between proteins, peptides, nucleic acids, lipids, and carbohydrates to mediate targeted accumulation and local anchoring of drugs and drug carriers. [Display omitted] [ABSTRACT FROM AUTHOR]

The use of excessive antibiotics in medical treatment and animal breeding has led to their prevalence in the environment and foods. Thereby, rapid, cheap, and sustainable techniques are required to detect and control the potential risk related to antibiotics. Actually, immunoassays have wide applications for this purpose, and improved assay formats with enzymatic, fluorescent, nanodispersed, and other tracers have enhanced the efficiency of the technique. However, there are several shortcomings of immunoassay due to the protein nature of antibodies. Thereby, molecular imprinting technology has evolved as growing artificial analytical receptor for molecular recognition with binding properties similar to natural antibodies. Molecularly imprinted polymers (MIPs) are defined as "plastibodies" or substitutes for antibodies in immunoassays. This review gives a general overview of the application of molecular imprinting to analytical systems, its state of art, and perspective. The application of MIP-based assays in the detection of antibiotics in food and environmental samples is explored herein. [ABSTRACT FROM AUTHOR]

Antibodies can recognize various types of antigens with high specificity and affinity and peptide is one of their major targets. Understanding an antibody's molecular recognition mechanism for peptide is important for developing clones with a higher specificity and affinity. Here, the author reviews recent progresses in flexible peptide recognition by an antibody using several biophysical techniques, including X-ray crystallography, molecular dynamics simulations and calorimetric measurements. A set of two reports highlight the importance of intramolecular hydrogen bonds that form in an unbound flexible state. Such intramolecular hydrogen bonds restrict the fluctuation of the peptide and reduce the conformational entropy, resulting in the destabilization of the unbound state and increasing the binding affinity by increasing the free energy change. These detailed analyses will aid in the antibody design in the future. [ABSTRACT FROM AUTHOR]

This is a delightful little book that captures many of the beauties of hydrogen bonding for high school and early college-going students, and yet it touches on some fairly advanced concepts. Armed with the chemical background in the early part of the book, it would not be difficult for a reader to appreciate that the hydrogen atom in chloroform is activated enough to function as a hydrogen bond donor. A good book triggers off many streams of thought in the mind of the reader and apart from young students of science who would really benefit from "The Hydrogen Bond. [Extracted from the article]

Reviews the book "Receptors and Recognition," Series A, Volume 6, by J. N. Fain.

The article reviews the book "Probes and Tags to Study Biomolecular Function for Proteins, RNA and Membranes," 1st Edition, edited by Lawrence W. Miller.

Reviews the book "Receptors and Recognition," Series A, Volume 5, by P. A. Lehmann and A. G. Lee.