Click Chemistry Protein Immobilization

The main purpose of the first part in the lab was to try and determine a way to measure the moles of dye per mole of protein in order to detect an azide tag on a recombinantly produced azide-IFN-γ protein. This was done by using click chemistry to bind the azide tagged protein to a dye and then measured the azide tag efficiency. The main purpose of the second part of the project was to make a protein, SDF-1α, and tag it with an azide group. This was completed via processes of expression, isolation, and purification of the protein. From here, an immobilization experiment was performed and a measure of the processes efficiency was recorded. A definite conclusion can be drawn that engineering a protein, expressing it, and purifying it can be completed. A conclusion that can be made from the first part of the experiment is to find a new method to move forward with when trying to measure the amount of azide that was tagged to the protein. No conclusions could be drawn from the second part, involving the immobilization process, due to an error in the kit used in the lab

Click chemistry within LDPE

Specialty LDPE copolymers provide some of the highest added value polyolefin applications and, in the quest to differentiate in an increasingly commoditized polyolefin environment, are of considerable interest to LDPE producers and other polyolefin players.1 In 2015, global specialty LDPE copolymers production was estimated around 6900 kT, from those EVA (Ethylene Vinyl Acetate) accounts for nearly 90 % of it.1 Other examples are EBA (Ethylene Butyl Acrylate), EVOH (Ethylene Vinyl Alcohol), COC (Cyclic Olefin Copolymer), MAH (Maleic AnHydride) grafted PE, … which all have their specific properties and are used in different kind of applications. All above mentioned commercial grades are made either by in reactor functionalization, copolymerization of ethylene and a monomer, or by post-modification, grafting of a monomer onto a PE backbone. A combination of both routes would give the advantage of producing one base grade; therefore, no changes in reactor settings are required and the properties of the polymer can be tuned by post-modification reactions. Please download the file below for full content

Stable covalently photo-cross-linked poly(ionic liquid) membrane with gradient pore size

An imidazolium-based poly(ionic liquid) is covalently cross-linked via UV light-induced thiolene (click) chemistry to yield a stable porous polyelectrolyte membrane with gradients of crosslink density and pore size distribution along its cross-section.Comment: 16 pages, 10 figure

Applications of Click Chemistry in Radiopharmaceutical Development

Click chemistry, a concept that employs only practical and reliable transformations for compound synthesis, has made a significant impact in several areas of chemistry, including material sciences and drug discovery. The present article describes the use of click chemistry for the development of radiopharmaceuticals. Target templated in situ click chemistry was used for lead generation. The 1,2,3-triazole moiety was found to improve the pharmacokinetic properties of certain radiopharmaceuticals. The reliable Cu(i)-catalyzed click reaction was employed for radiolabeling of peptidic compounds without the need for protecting groups. In summary, the click chemistry approach for the discovery, optimization and labeling of new radiotracers, represents a very powerful tool for radiopharmaceutical development

Iterative in Situ Click Chemistry Assembles a Branched Capture Agent and Allosteric Inhibitor for Akt1

We describe the use of iterative in situ click chemistry to design an Akt-specific branched peptide triligand that is a drop-in replacement for monoclonal antibodies in multiple biochemical assays. Each peptide module in the branched structure makes unique contributions to affinity and/or specificity resulting in a 200 nM affinity ligand that efficiently immunoprecipitates Akt from cancer cell lysates and labels Akt in fixed cells. Our use of a small molecule to preinhibit Akt prior to screening resulted in low micromolar inhibitory potency and an allosteric mode of inhibition, which is evidenced through a series of competitive enzyme kinetic assays. To demonstrate the efficiency and selectivity of the protein-templated in situ click reaction, we developed a novel QPCR-based methodology that enabled a quantitative assessment of its yield. These results point to the potential for iterative in situ click chemistry to generate potent, synthetically accessible antibody replacements with novel inhibitory properties

Green Approach in Click Chemistry

The aim of the topic on click chemistry is used to synthesize various derivatives of 1, 2, 3-triazol-1-yl piperazine, 1, 2, 3-triazol-1-yl quinoxaline, one pot 1,2,3-triazole and bistriazole. These various synthesized compounds were biologically active such as antimicrobial, anti-oxidant, anticancer, antiviral, anti HIV and antitubercular activates. The heterocyclic compounds which are pharmacological active were synthesized by the Cu (I)-catalyzed Huisgen 1, 3-dipolar cycloaddition is a major example based on the click chemistry philosophy. The click chemistry in a broad sense is about using easier reactions to make compounds for certain functions of drugs. The click chemistry used as a green synthesis, because it allows the basic principles of green chemistry given by Anastas and Warner

Cyclooctyne-based reagents for uncatalyzed click chemistry: A computational survey

With the goal of identifying alkyne-like reagents for use in click chemistry, but without Cu catalysts, we used B3LYP density function theory (DFT) to investigate the trends in activation barriers for the 1,3-dipolar cycloadditions of azides with various cyclooctyne, dibenzocyclooctyne, and azacyclooctyne compounds. Based on these trends, we find monobenzocyclooctyne-based reagents that are predicted to have dramatically improved reactivity over currently employed reagents

Copper Nanoparticles in Click Chemistry

Conspectus: The challenges of the 21st century demand scientific and technological achievements that must be developed under sustainable and environmentally benign practices. In this vein, click chemistry and green chemistry walk hand in hand on a pathway of rigorous principles that help to safeguard the health of our planet against negligent and uncontrolled production. Copper-catalyzed azide–alkyne cycloaddition (CuAAC), the paradigm of a click reaction, is one of the most reliable and widespread synthetic transformations in organic chemistry, with multidisciplinary applications. Nanocatalysis is a green chemistry tool that can increase the inherent effectiveness of CuAAC because of the enhanced catalytic activity of nanostructured metals and their plausible reutilization capability as heterogeneous catalysts. This Account describes our contribution to click chemistry using unsupported and supported copper nanoparticles (CuNPs) as catalysts prepared by chemical reduction. Cu(0)NPs (3.0 ± 1.5 nm) in tetrahydrofuran were found to catalyze the reaction of terminal alkynes and organic azides in the presence of triethylamine at rates comparable to those achieved under microwave heating (10–30 min in most cases). Unfortunately, the CuNPs underwent dissolution under the reaction conditions and consequently could not be recovered. Compelling experimental evidence on the in situ generation of highly reactive copper(I) chloride and the participation of copper(I) acetylides was provided. The supported CuNPs were found to be more robust and efficient catalyst than the unsupported counterpart in the following terms: (a) the multicomponent variant of CuAAC could be applied; (b) the metal loading could be substantially decreased; (c) reactions could be conducted in neat water; and (d) the catalyst could be recovered easily and reutilized. In particular, the catalyst composed of oxidized CuNPs (Cu2O/CuO, 6.0 ± 2.0 nm) supported on carbon (CuNPs/C) was shown to be highly versatile and very effective in the multicomponent and regioselective synthesis of 1,4-disubstituted 1,2,3-triazoles in water from organic halides as azido precursors; magnetically recoverable CuNPs (3.0 ± 0.8 nm) supported on MagSilica could be alternatively used for the same purpose under similar conditions. Incorporation of an aromatic substituent at the 1-position of the triazole could be accomplished using the same CuNPs/C catalytic system starting from aryldiazonium salts or anilines as azido precursors. CuNPs/C in water also catalyzed the regioselective double-click synthesis of β-hydroxy-1,2,3-triazoles from epoxides. Furthermore, alkenes could be also used as azido precursors through a one-pot CuNPs/C-catalyzed azidosulfenylation–CuAAC sequential protocol, providing β-methylsulfanyl-1,2,3-triazoles in a stereo- and regioselective manner. In all types of reaction studied, CuNPs/C exhibited better behavior than some commercial copper catalysts with regard to the metal loading, reaction time, yield, and recyclability. Therefore, the results of this study also highlight the utility of nanosized copper in click chemistry compared with bulk copper sources.This work was supported by the Spanish Ministerio de Economía y Competitividad, the Generalitat Valenciana, Fondo Europeo de Desarrollo Regional, the Argentinian Consejo Nacional de Investigaciones Científicas y Técnicas and Agencia Nacional de Promoción Científica Tecnológica, and the Instituto de Síntesis Orgánica (Universidad de Alicante)

Click Chemistry in Materials Science

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/106803/1/adfm201302847.pd