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Cleaning reagents are a common substance in every household and are used in everyday lives, especially after the outbreak of COVID-19 around the world. These have been part of the household for hundreds of years. It is essential to remove dirt and germs not only from the clothes but also from the human skin. It is also used to remove stains, dust or unpleasant odours from the body and the clothes. These are available in various forms, such as powders, granules, liquids and sprays. Cleaning reagents are generally manufactured in two ways: naturally and synthetically. The most frequently used synthetic cleaning agents are soaps, detergents, body cleansers, etc. But the environment is affected when the soap water or detergent water is disposed of through the sewage, which then eventually goes to the environment due to presence of non-biodegradable and toxic chemicals. So, it becomes necessary to replace these harmful cleaning reagents with the greener ones to reduce the harmful influence on the environment. Some of the green cleaning reagents are natural soaps, homemade products such as baking soda, lemon juice, vegetable oils and, plant and fruit extracts, HNT, microbial cleaning, biosurfactants, plants-based surfactants. This review article aims to focus on the greener cleaning reagents, which can be great alternatives compared to the present harmful cleaning reagents for better effects on the environment and for human safety.

A metal-free reusable hypervalent iodine(III) reagent is employed as a stable catalyst for the selective oxidation of active methylenes, indoles and styrene C-H bond to corresponding carbonyl compounds. From both economic and environmental point of view use of 2-Iodosobenzoic acid for oxidations replacing metals, makes the reaction interesting.

Quantitative Phase Imaging A reagent‐free hematology analyzer is developed in article number 2000277 by Rishikesh Pandey, Renjie Zhou, and co‐workers. The researchers employ a quantitative phase imaging in conjunction with a neural network to classify leukocytes. In the cover image, cells are illuminated by a laser and phase images are acquired by a custom‐built microscope (indicated by the objective lens). An AI algorithm (denoted by the background data flow) is used for classifying cells.

We recently developed ‘cellular’ reagents–lyophilized bacteria overexpressing proteins of interest–that can replace commercial pure enzymes in typical diagnostic and molecular biology reactions. To make cellular reagent technology widely accessible and amenable to local production with minimal instrumentation, we now report a significantly simplified method for preparing cellular reagents that requires only a common bacterial incubator to grow and subsequently dry enzyme-expressing bacteria at 37°C with the aid of inexpensive chemical desiccants. We demonstrate application of such dried cellular reagents in common molecular and synthetic biology processes, such as PCR, qPCR, reverse transcription, isothermal amplification, and Golden Gate DNA assembly, in building easy-to-use testing kits, and in rapid reagent production for meeting extraordinary diagnostic demands such as those being faced in the ongoing SARS-CoV-2 pandemic. Furthermore, we demonstrate feasibility of local production by successfully implementing this minimized procedure and preparing cellular reagents in several countries, including the United Kingdom, Cameroon, and Ghana. Our results demonstrate possibilities for readily scalable local and distributed reagent production, and further instantiate the opportunities available via synthetic biology in general.

Antibodies play a pivotal role in diagnostics, biomarkers research and increasingly in therapeutics. However in all three fields problems related to specificity and to consistency of the antibodies occur. Such problems are being kept to a minimum by the use of monoclonal antibodies, because of their immortality and for their single molecular basis. However, existing monoclonal antibodies have generally not been screened for the specific application it is currently required for. This leads to the use of antibodies with insufficient affinity for that particular application. In addition different formulations at which one antibody is offered to the market will cause inconsistencies in performance. Any polyclonal antibody is dismissed because it represents a mixture of different molecules, and therefore this mixture will change in composition from animal to animal thus changing the characteristics of the reagent from batch to batch. Although for therapeutics the best way to address these problems may be through the route of recombinant reagents (avoiding the animals altogether), one remains to be vigilant for cross-reactivity of reagents when reacting to a non-unique epitope. Here is a good opportunity to make the most of a cost-effective alternative for in vitro and for ex vivo tests; there is evidence that epitope-specific polyclonal antibodies offer an adequate alternative to unavailable fit-for-purpose monoclonal antibody.

Src homology 3 (SH3) domains play a critical role in mediating protein-protein interactions (PPIs) involved in cell proliferation, migration, and the cytoskeleton. Despite their abundance in the human proteome, the functions and molecular interactions of many SH3 domains remain unknown, and this is in part due to the lack of SH3 domain-specific reagents available for their study. Affimer proteins have been developed as affinity reagents targeting a diverse range of targets, including those involved in PPIs. The work presented in this thesis investigated the potential of using Affimer proteins to specifically bind SH3 domains to inhibit their interactions and functions. The Grb2 SH3 domains were chosen as proof-of-concept targets due to their role in linking activated RTKs to Ras-MAPK signalling via recruitment of SOS. Thus, the ability to impede Grb2 binding of SOS to restrict downstream signalling events was used to evaluate Affimer efficacy in inhibiting Grb2 SH3 interactions. In this project, Affimer proteins were isolated against the SH3 domains of Grb2 and PLCG1 by phage display. New methods for screening against individual SH3 domains tagged with either biotin acceptor peptide or glutathione S-transferase were developed in this project. The Affimer proteins were capable of binding target within full-length, endogenous protein and demonstrated binding specificity when tested in ELISAs against other SH3 domains. Furthermore, Affimer proteins targeting the N-terminal SH3 domain (SH3N) of Grb2 demonstrated inhibition of the interaction between Grb2 and a SOS-derived peptide. Affimer expression and function was also tested in mammalian cells. Affimer C-C12, a binder of the C-terminal SH3 domain (SH3C) of Grb2, demonstrated inhibition of Ras-MAPK and PI3K/Akt signalling by reducing levels of phosphorylated ERK and phosphorylated Akt in HEK-293 and U-2 OS cells activated with epidermal growth factor. Overall, the work presented in this thesis has provided evidence that Affimer reagents can be used to study the function of SH3 domain interactions in cells.

Most currently used catalysts for the amination of C–H bonds are ill suited to the functionalization of complex molecules; here it is shown that a mild, selective, iron-catalysed azidation of tertiary C–H bonds is suitable for the amination of complex molecules containing a range of functional groups. Convenient C–H amination in complex molecules Synthetic chemists are keen to identify catalysts that directly convert C–H bonds to C–N bonds. Natural enzymes are not available for this amination reaction and most currently used chemical catalysts are ill-suited for the functionalization of complex molecules. In this manuscript, the authors report an iron catalysed, highly selective azidation of tertiary C–H bonds under conditions with substrate as the limiting reagent. The reaction tolerates aqueous environments and is suitable for 'late-stage' functionalization of complex structures, as demonstrated by the azidation of tetrahydrogibberellic acid, a complex and medicinally relevant molecule. Many enzymes oxidize unactivated aliphatic C–H bonds selectively to form alcohols; however, biological systems do not possess enzymes that catalyse the analogous aminations of C–H bonds 1 , 2 . The absence of such enzymes limits the discovery of potential medicinal candidates because nitrogen-containing groups are crucial to the biological activity of therapeutic agents and clinically useful natural products. In one prominent example illustrating the importance of incorporating nitrogen-based functionality, the conversion of the ketone of erythromycin to the –N(Me)CH 2 – group in azithromycin leads to a compound that can be dosed once daily with a shorter treatment time 3 , 4 . For such reasons, synthetic chemists have sought catalysts that directly convert C–H bonds to C–N bonds. Most currently used catalysts for C–H bond amination are ill suited to the intermolecular functionalization of complex molecules because they require excess substrate or directing groups, harsh reaction conditions, weak or acidic C–H bonds, or reagents containing specialized groups on the nitrogen atom 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 . Among C–H bond amination reactions, those forming a C–N bond at a tertiary alkyl group would be particularly valuable, because this linkage is difficult to form from ketones or alcohols that might be created in a biosynthetic pathway by oxidation 15 . Here we report a mild, selective, iron-catalysed azidation of tertiary C–H bonds that occurs without excess of the valuable substrate. The reaction tolerates aqueous environments and is suitable for the functionalization of complex structures in the late stages of a multistep synthesis. Moreover, this azidation makes it possible to install a range of nitrogen-based functional groups, including those from Huisgen ‘click’ cycloadditions and the Staudinger ligation 16 , 17 , 18 , 19 . We anticipate that these reactions will create opportunities to modify natural products, their precursors and their derivatives to produce analogues that contain different polarity and charge as a result of nitrogen-containing groups. It could also be used to help identify targets of biologically active molecules by creating a point of attachment—for example, to fluorescent tags or ‘handles’ for affinity chromatography—directly on complex molecular structures.

Palladium( ii ) complexes can be used in efficient and highly selective cysteine conjugation reactions that are rapid and robust, and the resulting aryl bioconjugates are stable towards acids, bases, oxidants and external thiol nucleophiles. A new route to S -aryl conjugates These authors demonstrate that palladium( II ) complexes can be used in efficient and highly selective cysteine conjugation reactions that are rapid and robust, and the resulting aryl bioconjugates are stable towards acids, bases, oxidants and external thiol nucleophiles. The broad utility of the new bioconjugation platform was further corroborated by the synthesis of new classes of stapled peptides and antibody–drug conjugates. Previously the use of transition-metal based reactions to modify complex biomolecules has proved problematic due mainly to the need for stringent reaction conditions and the presence of multiple reactive functional groups in peptides. Reactions based on transition metals have found wide use in organic synthesis, in particular for the functionalization of small molecules 1 , 2 . However, there are very few reports of using transition-metal-based reactions to modify complex biomolecules 3 , 4 , which is due to the need for stringent reaction conditions (for example, aqueous media, low temperature and mild pH) and the existence of multiple reactive functional groups found in biomolecules. Here we report that palladium( ii ) complexes can be used for efficient and highly selective cysteine conjugation (bioconjugation) reactions that are rapid and robust under a range of bio-compatible reaction conditions. The straightforward synthesis of the palladium reagents from diverse and easily accessible aryl halide and trifluoromethanesulfonate precursors makes the method highly practical, providing access to a large structural space for protein modification. The resulting aryl bioconjugates are stable towards acids, bases, oxidants and external thiol nucleophiles. The broad utility of the bioconjugation platform was further corroborated by the synthesis of new classes of stapled peptides and antibody–drug conjugates. These palladium complexes show potential as benchtop reagents for diverse bioconjugation applications.