Aziridinofullerene: a versatile platform for functionalized fullerenes

An aziridine moiety on the fullerene core can serve as an acid-triggered reacting template for the controlled synthesis of a range of functionalized fullerenes that are otherwise difficult to synthesize in an efficient and selective manner. A copper-catalyzed aziridination of C(60) for the practical synthesis of aziridinofullerene 1 and acid-catalyzed reactions of 1 with mono- and bifunctional nucleophiles as well as alkynes are described. The rapid generation of structural diversity in a single chemical operation using the common platform 1 is notable.     

Nucleoside optimization for RNAi: a high-throughput platform

The RNA induced silencing complex (RISC) contains at its core the endonuclease Argonaute (Ago) that allows for guide strand (GS)-mediated sequence-specific cleavage of the target mRNA. Functionalization of the sugar/phosphodiester backbone of the GS, which is in direct contact with Ago, presents a logical opportunity to affect RISC's activity. A systematic evaluation of modified nucleosides requires the synthesis of phosphoramidites corresponding to all four canonical bases (A, U, C, and G) and their sequential evaluation at each position along the 21-nucleotide-long GS. With the use of a platform approach, the sequential replacement of canonical bases with inosine greatly simplifies the problem and defines a new activity baseline toward which the corresponding sugar-modified inosines are compared. This approach was validated using 2'-O-benzyl modification, which demonstrated that positions 5, 8, 15, and 19 can accommodate this large group. Application of this high-throughput methodology now allows for hypothesis-driven rational design of highly potent, immunologically silent and stable siRNAs suitable for therapeutic applications.     

Polymer-supported thioanisole: a versatile platform for organic synthesis reagents

A new cross-linked polystyrene-supported thioanisole reagent is reported. This reagent incorporates the flexible JandaJel™ cross-linker and can be treated with methyl trifluoromethanesulfonate to form the corresponding sulfonium salt. This salt can in turn be deprotonated to form a polymer-supported sulfur ylide that is able to react with aldehydes and ketones to form epoxides. The thioanisole reagent can also be oxidized to form an insoluble sulfoxide reagent that is useful in Swern oxidation reactions. In these reactions, the polymer-supported thioanisole-based reagents can be recovered, regenerated and reused.     

Dendrimer as a versatile platform for biomedical application: A review

Modern chemistry is vastly fascinated by dendrimer chemistry, an area that is rapidly expanding and brimming with potential applications. Dendrimers are highly branched polymers that have multiple peripheral groups, interior cavities and they have many structural properties therefore Dendrimers play a crucial role in the fields of nanotechnology, pharmaceuticals, and medicinal chemistry. The terminal functional groups of dendrimers may be chemically linked to other moieties in order to adjust surface properties for applications such as biomimetic nanodevices. A variety of biologically active agents can be incorporated into dendrimers to create biologically active conjugates, including novel drug carriers, by utilizing the homogeneity of their three-dimensional architecture. The purpose of this review is to provide a brief overview of bio-inspired dendrimer applications, highlighting their use as drug and gene delivery agents, and biomedical diagnostic agents. In addition, the review mentions briefly some dendrimer applications in cosmetics, agrochemicals, and catalyst.     

Iodinated polyesters as a versatile platform for radiopaque biomaterials

The design of polymeric biomaterials with long‐lasting X‐ray contrast could advance safe and effective implants and contrast agents. Herein, a new set of wholly aliphatic, iodinated polyesters are synthesized and evaluated as high‐contrast biomaterials and nanoparticle contrast agents for general computed tomography imaging. A single iodinated monomer is used to synthesize a variety of aliphatic polyesters with tunable thermal and mechanical properties. These iodinated polyesters are end‐functionalized with a photocurable methacrylate group, which allows easy processability. The resulting materials exhibit no cytotoxicity and are radiopaque, containing over 40% iodine by weight after processing. The polymers can be formulated into lipid–polymer hybrid nanoparticles using a modified nanoprecipitation method. Initial studies indicate that these nanoparticles show good continual contrast over 60 minutes with no uptake into the kidneys. The work presented here illustrates a novel platform for iodinated polyesters that exhibit high radiopacity and processability, low cost, and no cytotoxicity. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 2171–2177     

Microarray technology as a universal tool for high-throughput analysis of biological systems

Over the last years microarray technology has become one of the principal platform technologies for the high-throughput analysis of biological systems. Starting with the construction of first DNA microarrays in the 1990s, microarray technology has flourished in the last years and many different new formats have been developed. Peptide and protein microarrays are now applied for the elucidation of interaction partners, modification sites and enzyme substrates. Antibody microarrays are envisaged to be of high importance for the high-throughput determination of protein abundances in translational profiling approaches. First cell microarrays have been constructed to transform microarray technology from an in vitro technology to an in vivo functional analysis tool. All of these approaches share a common prerequisite: the solid support on which they are generated. The demands on this solid support are thereby as manifold as the applications themselves. This review is aimed to display the recent developments in surface chemistry and derivatization, and to summarize the latest developments in the different application areas of microarray technology.     

Interpretation of mass spectrometry data for high-throughput proteomics

Recent developments in proteomics have revealed a bottleneck in bioinformatics: high-quality interpretation of acquired MS data. The ability to generate thousands of MS spectra per day, and the demand for this, makes manual methods inadequate for analysis and underlines the need to transfer the advanced capabilities of an expert human user into sophisticated MS interpretation algorithms. The identification rate in current high-throughput proteomics studies is not only a matter of instrumentation. We present software for high-throughput PMF identification, which enables robust and confident protein identification at higher rates. This has been achieved by automated calibration, peak rejection, and use of a meta search approach which employs various PMF search engines. The automatic calibration consists of a dynamic, spectral information-dependent algorithm, which combines various known calibration methods and iteratively establishes an optimised calibration. The peak rejection algorithm filters signals that are unrelated to the analysed protein by use of automatically generated and dataset-dependent exclusion lists. In the "meta search" several known PMF search engines are triggered and their results are merged by use of a meta score. The significance of the meta score was assessed by simulation of PMF identification with 10,000 artificial spectra resembling a data situation close to the measured dataset. By means of this simulation the meta score is linked to expectation values as a statistical measure. The presented software is part of the proteome database ProteinScape which links the information derived from MS data to other relevant proteomics data. We demonstrate the performance of the presented system with MS data from 1891 PMF spectra. As a result of automatic calibration and peak rejection the identification rate increased from 6% to 44%.Abbreviations 2-DE Two-dimensional gel electrophoresis - MALDI Matrix-assisted laser desorption ionisation - PMF Peptide mass fingerprinting - MS Mass spectrometry - TOF Time of flight     

L-glutamic acid as a versatile platform for rapid synthesis of functional polyesters via facile Passerini multicomponent polymerization

In this work, a series of polyesters with different functional side groups were successfully prepared by Passerini three-component polymerization (P-3CP) in “one-pot” from biorenewable l -glutamic acid (l -GA)-based monomers. First, the polymerization conditions including monomer feed ratios, solvents and comonomer were systematically studied using Boc-protected l -GA with adipaldehyde and tert-butyl isocyanide. Under the optimal polymerization conditions, a variety of N-substituted l -GA-based monomers as well as functional isocyanides were attempted in the P-3CP to produce polyesters with different functionalities. Moreover, it was found that after removal of pendant protecting groups, the obtained l -GA-based polyester degraded spontaneously into small molecules via 1,5-intramolecular cyclization between the pendant amine groups and the ester groups in polymer backbone. The structures and thermal properties of obtained polymers were determined by ¹H NMR, IR, SEC, MALDI-ToF-MS, DSC, and TGA measurements. Starting from biorenewable l -GA, this approach will provide a facile and straightforward route to produce functional and biodegradable polyesters, thus effectively expanding the range of biodegradable polymers.     

Versatile protein biotinylation strategies for potential high-throughput proteomics

We present intein-mediated approaches for efficient biotinylation of proteins site-specifically. The reactive C-terminal thioester generated from intein-assisted protein splicing (either in vitro or in live cells) served as an attractive and exclusive site for attaching cysteine-containing biotin. Using these novel biotinylation strategies, we were able to efficiently biotinylate many proteins from different biological sources in a potentially high-throughput, high-content fashion. Some of these proteins were subsequently immobilized, in a very simple manner, onto different avidin-functionalized solid surfaces for applications such as protein microarray and surface plasmon resonance (SPR) spectroscopy, highlighting the numerous advantages of using biotin over other tags (e.g., GST, His-tag, etc.) as the method of choice in protein purification/immobilization. In addition, our intein-mediated strategies provided critical advantages over other protein biotinylation strategies in a number of ways. For the first time, we also successfully demonstrated that intein-mediated protein biotinylation proceeded adequately inside both bacterial and mammalian living cells, as well as in a cell-free protein synthesis system. Taken together, our results indicate the versatility of these intein-mediated strategies for potential high-throughput proteomics applications. They may also serve as useful tools for various biochemical and biophysical studies of proteins both in vitro and in vivo.     

Poly(allyl glycidyl ether)-A versatile and functional polyether platform

Allyl glycidyl ether, polymerized from potassium alkoxide/naphthalenide initiators under both neat and solution conditions was shown to be a highly-controlled process. In both cases, molar masses (10-100 kg/mol) were determined by the reaction stoichiometry, and low polydispersity indices (1.05-1.33) could be obtained with a full understanding of the dominant side reaction, isomerization of the allyl side chain, being developed. The degree of isomerization of allyl to cis-prop-1-enyl ether groups (0 - 10 % mol.) was not correlated to the molar mass or polydispersity of the polymer but was dictated by the polymerization temperature. This allows the extent of isomerization to be reduced to essentially zero under either melt or solution conditions at polymerization temperatures of less than 40 °C.     

One-step preparation of vinyl-functionalized material surfaces: a versatile platform for surface modification

A simple approach has been developed to functionalize various substrates, such as gold and polyvinylchloride, with dopamine methacrylamide—a molecule with adhesive properties that mimic those of mussels—to produce a versatile and general platform for subsequent surface modification. With active double bonds on the surface, various polymers, such as poly([2-(methacryloyloxy)ethyl]dimethyl-(3-sulfopropyl) ammonium hydroxide(PMEDSAH) and poly(N-vinylpyrrolidone)(PVP), can be grafted by conventional radical polymerization. Double bond surface functionalization and subsequent polymer grafting have been verified by static water contact angle, Fourier transform infrared–attenuated total reflectance(FTIR-ATR) spectroscopy and X-ray photoelectron spectroscopy(XPS) measurements. Protein adsorption assays showed that the polymermodified substrates have good protein-resistant properties. Considering the advantages of facility, versatility and substrate- independence, this method should be useful in designing functional interfaces for bioengineering applications.     

A novel mass spectrometry cluster for high-throughput quantitative proteomics

We have developed and implemented a novel mass spectrometry (MS) platform combining the advantages of high mass accuracy and resolving power of Fourier transform ion cyclotron resonance (FTICR) with the economy and speed of multiple ion traps for tandem mass spectrometry. The instruments are integrated using novel algorithms and software and work in concert as one system. Using chromatographic time compression, a single expensive FTICR mass spectrometer can match the throughput of multiple relatively inexpensive ion trap instruments. Liquid chromatography (LC)-mass spectrometry data from the two types of spectrometers are aligned and combined to hybrid datasets, from which peptides are identified using accurate mass from the FTICR data and tandem mass spectra from the ion trap data. In addition, the high resolving power and dynamic range of a 12 tesla FTICR also allows precise label-free quantitation. Using two ion traps in parallel with one LC allows simultaneous MS/MS experiments and optimal application of collision induced dissociation and electrontransfer dissociation throughout the chromatographic separation for increased proteome coverage, characterization of post-translational modifications and/or simultaneous measurement in positive and negative ionization mode. An FTICR-ion trap cluster can achieve similar performance and sample throughput as multiple hybrid ion trap-FTICR instruments, but at a lower cost. We here describe the first such FTICR-ion trap cluster, its performance and the idea of chromatographic compression.     

Modular synthesis of functional polymer nanoparticles from a versatile platform based on poly(pentafluorophenylmethacrylate)

Control of functionalities in polymer nanoparticles (PNPs) is important for their application. Thus, there is an interest for well‐defined nanoparticle platforms to which desired functions could readily, and in modular fashion, be imparted. Herein, we report an amine‐reactive PNP platform for the modular synthesis of functional PNPs from poly(pentafluorophenylmethacrylate) (poly(PFPMA)) through a simple substitution/nanoprecipitation/photo‐crosslinking strategy. Substitution of amine containing coumarin into poly(PFPMA) allows for the achievement of structural stability of nanoprecipitated particles through photo‐crosslinking after nanoprecipitation, making it possible to carry out subsequent chemical transformations in organic solvents if needed. We demonstrate that various small molecules and an amine‐terminated polymer could be used to modify the crosslinked PNPs to endow them with various functions including fluorescence and responsiveness to temperature changes. The functional PNPs were characterized with variable temperature dynamic light scattering (DLS), UV–vis, and photoluminescence (PL) spectroscopy, and transmission electron microscopy (TEM). © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 1895–1901     

A versatile QCM matrix system for online and high-throughput bio-sensing

A 3 x 3 quartz crystal microbalance (QCM) sensor matrix, fabricated on an A-T cut quartz crystal, has the ability to detect online a variety of labeled DNA samples in a parallel and comparative fashion. The QCM matrix was equipped with a single oscillator circuit, which activated only one QCM at any given time, and was controlled by programmable time-shared electronic relays. The gold electrode had a diameter of 0.8 mm and operated at a fundamental resonating frequency of 40 MHz; the dimensions of the matrix were 1.2 cm x 1.2 cm. The sensitivity of an individual QCM was in the pictogram regime. Selected QCMs were coated with either streptavidin or the anti-DIG antibody; the specificity of their detections was monitored using various concentrations of samples of biotin- and DIG-labeled DNA. The basic design of the QCM matrix is readily expandable, without any conceivable difficulties, in both geometry and circuitry.     

'Fab-chips': a versatile, fabric-based platform for low-cost, rapid and multiplexed diagnostics

Low cost and scalable manufacture of lab-on-chip devices for applications such as point-of-care testing is an urgent need. Weaving is presented as a unified, scalable and low-cost platform for the manufacture of fabric chips that can be used to perform such testing. Silk yarns with different properties are first selected, treated with the appropriate reagent solutions, dried and handloom-woven in one step into an integrated fabric chip. This platform has the unique advantage of scaling up production using existing and low cost physical infrastructure. We have demonstrated the ability to create pre-defined flow paths in fabric by using wetting and non-wetting silk yarns and a Jacquard attachment in the loom. Further, we show that yarn parameters such as the yarn twist frequency and weaving coverage area may be conveniently used to tune both the wicking rate and the absorptive capacity of the fabric. Yarns optimized for their final function were used to create an integrated fabric chip containing reagent-coated yarns. Strips of this fabric were then used to perform a proof-of-concept immunoassay with sample flow taking place by capillary action and detection being performed by a visual readout.     

A new versatile receptor platform

We prepared a molecular receptor based on the molecular tweezer concept. Our system offers versatility, an extremely short synthetic route, good yield, large quantities, and finally having binding constants that equal the best known tweezer molecules when it comes to binding various nitroaromatics such as 1,3,5-trinitrotoluene (24 M(-1)), 1,3,5-trinitrobenzene (182 M(-1)), and 2,4,7-trinitrofluorenone (490 M(-1)) as determined using 1H NMR in CDCl3. It is notable that these binding constants are achieved although the molecular framework is not locked in a fixed and rigid conformation. The rigidity has been claimed to be the governing factor when it comes to achieving a large binding constant. We propose that our molecular tweezer system may be preorganized and that this explains the high binding constants observed. Further, we investigated the crystal structures of both the neutral receptor molecule and a complex with 1,3,5-trinitrobenzene and found that the molecule forms a pocket suited to accommodate flat aromatic analytes.     

Microarray platform for profiling enzyme activities in complex proteomes

Activity-based protein profiling (ABPP) is a chemical method that utilizes active-site-directed probes to determine the functional state of enzymes in complex proteomes. Probe-labeled enzymes are typically detected by in-gel fluorescence scanning, a robust technique that nonetheless exhibits some key deficiencies, including limited sensitivity and resolution, as well as ambiguity regarding the molecular identity of the enzymes under investigation. Here, we report a microarray platform for ABPP that addresses these limitations. In this platform, proteomes are treated with ABPP probes in solution, after which labeled enzymes are captured and visualized on glass slides displaying an array of anti-enzyme antibodies. We show that ABPP microarrays exhibit superior sensitivity and resolution compared to gel-based methods, permitting the parallel analysis of several enzyme activities in proteomes, including cancer-associated proteases such as urokinase, matrix metalloproteinase-9, and prostate-specific antigen.