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Protein crystallography (PX) is widely used to drive advanced stages of drug optimization or to discover medicinal chemistry starting points by fragment soaking. However, recent progress in PX could allow for a more integrated role into early drug discovery. Here, we demonstrate for the first time the interplay of high throughput synthesis and high throughput PX. We describe a practical multicomponent reaction approach to acrylamides and -esters from diverse building blocks suitable for mmol scale synthesis on 96-well format and on a high-throughput nanoscale format in a highly automated fashion. High-throughput PX of our libraries efficiently yielded potent covalent inhibitors of the main protease of the COVID-19 causing agent, SARS-CoV-2. Our results demonstrate, that the marriage of in situ HT synthesis of (covalent) libraires and HT PX has the potential to accelerate hit finding and to provide meaningful strategies for medicinal chemistry projects., (© 2021 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

A new phosphine is proposed as efficient coinitiator for camphorquinone (CQ)-based photoinitiating systems for the free radical polymerization of (meth)acrylates. Remarkably, this new co-initiator can exhibit two functionalities: a phosphine moiety to overcome oxygen inhibition and an iodonium salt moiety as counter cation to initiate the polymerization process. Excellent polymerization performances in the presence of CQ for the free radical polymerization of methacrylates under blue light are observed, and amine-free systems can be easily developed from the proposed structure. The photopolymerization of composites is also investigated in the presence of the new phosphine (without iodonium counter cation) and very interesting depth of cure can be obtained from the new developed photoinitiating system after only 20 s of irradiation with a blue light-emitting diode., (© 2020 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A straightforward transformation protocol combining two distinct living polymerization methods for the controlled synthesis of block copolymers is described. In the first step, bromo-terminated poly(methyl methacrylate) is prepared by atom transfer radical polymerization (ATRP). Then, a bromide end group is substituted with a triphenylmethyl (trityl) functionality under visible light irradiation using dimanganese decacarbonyl (Mn 2 (CO) 10 ) photochemistry. The resulting polymers with trityl end groups are used as macroiniferter for the polymerization of styrene and tert-butyl acrylate (tBA) to yield desired block copolymers with narrow molecular weight distribution. Moreover, the amphiphilic copolymers with acrylic acid functionalities are obtained by the hydrolyzation of poly(tert-butyl acrylate) containing block copolymers with trifluoroacetic acid., (© 2019 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A hypervalent (HV) iodine(III)-containing crosslinker, (diacryloyloxyiodo)benzene, is synthesized and its crystal structure is reported. Highly branched polymers with hypervalent iodine(III) groups as the building blocks present at the branching points are synthesized by copolymerization of tert-butyl acrylate and the diacrylate crosslinker (up to 12 mol% vs the monovinyl monomer), under reversible deactivation radical polymerization (iodine transfer polymerization) conditions, which are employed to ensure that the incorporation of the crosslinker into the polymer chains is slow and gradual, that is, to limit the average number of pendant double bonds per chain and delay gelation. The branched polymers with (diacyloxyiodo)benzene-type linkers are responsive and react with monocarboxylic acids, for example, acetic acid, which participate in ligand-exchange reactions with the HV iodine(III) centers, and with reducing agents, for example, tributylphosphine, which reduce iodine(III) to iodine(I); both reactions lead to polymer degradation with the formation of random linear copolymers of tert-butyl acrylate and acrylic acid., (© 2019 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The beneficial use of computer simulations to track the microstructural evolution of individual species is highlighted in view of macromolecular engineering and design, considering two case studies on catalytic polymerization, and both "low" (<100) and "high" (>100) chain lengths, that is, i) atom transfer radical copolymerization of n-butyl acrylate and styrene aiming at the synthesis of functional macrospecies of "identical' chain length; and ii) chain shuttling polymerization of ethylene and 1-octene toward the production of segmented block copolymers with "soft" and "hard" segments. Model parameters are validated and/or tuned based on literature data. The modeling strategy supports the future identification of chemical structure-polymer property relationships and is based on the combination of principles from polymer reaction engineering, chemistry, and physics., (© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A strategy for the synthesis of sequence-defined oligomers using a selective side-group insertion approach making use of thiophenol-catalyzed amidation reactions is herein reported. In this context, a new thiolactone-based, multistep, iterative protocol is designed, utilizing thioacrylates in combination with solid-phase synthesis for step-by-step growth, resulting in sequence-defined oligomers. Sequence definition and structure variation are introduced by substituting the thioacrylate side groups with a wide variety of amines. The step-by-step growth of the oligomers is followed by liquid chromatography-mass spectrometry and high-resolution mass spectroscopy to determine both conversion and purity., (© 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Butyl acrylate is polymerized in the living way under the irradiation of purple light-emitting diode (LED) or sunlight without photocatalyst at ambient temperature. 2-((Phenoxycarbonothioyl)thio) ethyl propanoate) is exclusively added and acted as an initiator and a chain transfer agent simultaneously in the current system. Poly(butyl acrylate) with well-regulated molecular weight and relatively narrow molecular weight distribution (Ð < 1.30) is synthesized. High conversion (>95%) can be achieved within several minutes. Polymerization shows oxygen tolerance. Near quantitative end-group fidelity of polymer is demonstrated by 1 H NMR and matrix-assisted laser desorption/ionization time-of-flight mass spectra., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Despite being a simple dehydration reaction, the industrially relevant conversion of lactic acid to acrylic acid is particularly challenging. For the first time, the catalytic cracking of lactide and poly(lactic acid) to acrylic acid under mild conditions is reported with up to 58 % yield. This transformation is catalyzed by strong acids in the presence of bromide or chloride salts and proceeds through simple S N 2 and elimination reactions., (© 2017 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.)

Hydrogels based upon terpolymers of methacrylic acid, N-vinyl pyrrolidone, and poly(ethylene glycol) are developed and characterized for their ability to respond to changes in environmental pH and to partition protein therapeutics of varying molecular weights and isoelectric points. P((MAA-co-NVP)-g-EG) hydrogels are synthesized with PEG-based cross-linking agents of varying length and incorporation densities. The composition is confirmed using FT-IR spectroscopy and shows peak shifts indicating hydrogen bonding. Scanning electron microscopy reveals microparticles with an irregular, planar morphology. The pH-responsive behavior of the hydrogels is confirmed under equilibrium and dynamic conditions, with the hydrogel collapsed at acidic pH and swollen at neutral pH. The ability of the hydrogels to partition model protein therapeutics at varying pH and ionic strength is evaluated using three model proteins: insulin, porcine growth hormone, and ovalbumin. Finally, the microparticles are evaluated for adverse interactions with two model intestinal cell lines and show minimal cytotoxicity at concentrations below 5 mg mL -1 ., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Acid chlorides are an important class of compounds and their high reactivity and instability has prompted us to develop a straightforward procedure for their synthesis with on-demand and on-site synthesis possibilities. The focus of this report is acryloyl chloride, mainly important for the acrylate and polymer industry. A continuous-flow methodology was developed for the fast and selective synthesis of the otherwise highly unstable acryloyl chloride. Three routes were investigated in a microreactor setup and all three can potentially be used for its production. The methodology was further expanded to the synthesis of other unstable acid chlorides by both the thionyl chloride and the oxalyl chloride mediated processes. The most sustainable method was the oxalyl chloride mediated procedure under solvent-free conditions, in which near-equimolar amounts of carboxylic acid and oxalyl chloride were used in the presence of catalytic amounts of DMF at room temperature. Within 1 to 3 min, nearly full conversions into the acid chlorides were achieved., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

In a recent publication, Nakamura and co-workers studied the termination mechanism in the radical polymerization of acrylates. Contrary to conventional thinking, their conclusion is that termination is overwhelmingly by disproportionation. This finding impacts on a large body of the previous work in the polymerization of acrylic monomers which this work seeks to address. Analysis of the molecular weight distribution of acrylic polymers obtained under different polymerization conditions shows that termination by combination is the more probable mechanism for mutual termination of secondary radicals. It is proposed that in the experiments conducted by Nakamura and co-workers, backbiting plays a key role and their experimental data are reinterpreted, showing that they are more revealing with respect to the mode of termination of the midchain radical produced by backbiting, than to bimolecular termination of secondary radicals., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Various polymerization mechanisms have been developed to prepare peptide-immobilized poly(ethylene glycol) (PEG) hydrogels, a class of biomaterials suitable for studying cell biology in vitro. Here, a visible light mediated thiol-acrylate photopolymerization scheme is reported to synthesize dually degradable PEG-peptide hydrogels with controllable crosslinking and degradability. The influence of immobilized monothiol pendant peptide is systematically evaluated on the crosslinking of these hydrogels. Further, methods are proposed to modulate hydrogel crosslinking, including adjusting concentration of comonomer or altering the design of multifunctional peptide crosslinker. Due to the formation of thioether ester bonds, these hydrogels are hydrolytically degradable. If the dithiol peptide linkers used are susceptible to protease cleavage, these thiol-acrylate hydrogels can be designed to undergo partial proteolysis. The differences between linear and multiarm PEG-acrylate (i.e., PEGDA vs PEG4A) are also evaluated. Finally, the use of the mixed-mode thiol-acrylate PEG4A-peptide hydrogels is explored for in situ encapsulation of hepatocellular carcinoma cells (Huh7). The effects of matrix stiffness and integrin binding motif (e.g., RGDS) on Huh7 cell growth and HIPPO pathway activation are studied using PEG4A-peptide hydrogels. This visible light poly-merized thiol-acrylate hydrogel system represents an alternative to existing light-cured hydrogel platforms and shall be useful in many biomedical applications., Competing Interests: The authors declare no conflict of interest., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The branching stemming from midchain radical formation in n-butyl acrylate polymerization is investigated via melt-state (13) C NMR measurements. The dependence of the degree of branching (DB) on the monomer conversion of the system is examined for photoinduced polymerizations, revealing a steady increase in branching with conversion. For polymerization at moderate light intensities, an increase in branching from 0.03% to 0.37% is observed for polymerizations at 60 °C, which is fivefold below the level of branching observed in thermally initiated polymerizations under otherwise identical reaction conditions. The reason for this overall reduction in branching remains momentarily unclear; yet, a strong dependence of branching on light intensity is observed. While polymerization under a 1 W LED lamp results at almost full monomer conversion in branching degrees of 0.22%, polymerization under a 400 W lamp yields 1.81% of chain branches., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Hollow bioactive glass spheres with mesoporous shells were prepared by using dual soft templates, a diblock co-polymer poly(styrene-b-acrylic acid) (PS-b-PAA) and a cationic surfactant cetyltrimethylammonium bromide (CTAB). Hollow mesoporous bioactive glass (HMBG) spheres comprise the large hollow interior with vertical mesochannels in shell, which realize large uptake of drugs and their sustained release. The formation of hydroxyapatite layer on the surface of HMBG particles shows the clear evidence for promising application in bone regeneration., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Novel 2-(β-maltooligooxy)-ethyl (meth)acrylate monomers are successfully synthesized by CGTase from Bacillus macerans catalyzed coupling of 2-(β-glucosyloxy)-ethyl acrylate and methacrylate with α-cyclodextrin or starch. HPLC-UV analysis shows that the CGTase catalyzed reaction yields 2-(β-maltooligooxy)-ethyl acrylates with 1 to 15 glucopyranosyl units. (1) H NMR spectroscopy reveals that the β-linkage in the acceptor molecule is preserved during the CGTase catalyzed coupling reaction, whereas the newly introduced glucose units are attached by α-(1,4)-glycosidic linkages. The synthesized 2-(β-maltooligooxy)-ethyl acrylate monomers are successfully polymerized by aqueous free radical polymerization to yield the comb-shaped glycopolymer poly(2-(β-maltooligooxy)-ethyl acrylate)., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Various cellulase preparations were found to catalyze the transglycosidation between cotton linters and 2-hydroxyethyl acrylate. The conversion and enzyme activity were found to be optimal in reaction mixtures that contained 5 vol % of the acrylate. The structures of the products were revealed by using TLC and (1) H and (13) C NMR spectroscopy. The enzyme-catalyzed reaction resulted in two products. The minor product originated from transglycosidation to hemicellulose and was found to be 2-(β-xylosyloxy)-ethyl acrylate. The major product was identified as 2-(β-glucosyloxy)-ethyl acrylate and the yield of the product was 5 wt % based on the amount of consumed cellulose. Glycosidation products with oligosaccharide moieties could not be detected in the reaction mixture. This result can be explained by the hydrolytic activities of the used cellulase preparation. Cellulase from Trichoderma reesei was found to possess, in addition to endoglucanase activity, cellobiosidase and β-glucosidase activities. Five other cellulase preparations from different origins were tested as well for catalysis of oligosaccharide acrylate synthesis. For most cellulase preparations the major transglycosidation product appeared to be 2-(β-glucosyloxy)-ethyl acrylate. Nevertheless, the endo-β-(1,4)-glucanase from Trichoderma longibrachiatum was found to catalyze the synthesis of 2-(β-cellobiosyloxy)-ethyl acrylate. Unlike the other cellulase preparations, endo-β-(1,4)-glucanase from T. longibrachiatum showed no detectable β-glucosidase activity and therefore oligosaccharide acrylate monomers were not further hydrolyzed into the monosaccharide acrylate 2-(β-glucosyloxy)-ethyl acrylate., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Background autofluorescence from biological systems generally reduces the sensitivity of a fluorescent probe for imaging biological targets. Addressing this challenge requires the development of fluorescent probes that produce emission in the near-infrared region. Herein, we report the design and synthesis of a fluorescent probe that generates an NIR emission with a large Stokes shift upon the selective response to Cys over Hcy and GSH. The probe is designed to consist of two Cys-sensing sites, an acrylate ester and an aldehyde installed ortho to each other. The reaction of the probe with Cys triggers an excited state intramolecular proton transfer process upon photo-excitation, thereby producing an NIR emission with a large Stokes shift. Accordingly, this probe hold great promise for the selective detection of Cys in biological systems. We further demonstrate the capacity of this probe for Cys imaging in living cells., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Bio-based polymer materials from renewable resources have recently become a growing research focus. Herein, a novel thermoplastic elastomer is developed via controlled/living radical polymerization of plant-derived itaconic acid derivatives, which are some of the most abundant renewable acrylic monomers obtained via the fermentation of starch. The reversible addition-fragmentation chain-transfer (RAFT) polymerizations of itaconic acid imides, such as N-phenylitaconimide and N-(p-tolyl)itaconimide, and itaconic acid esters, such as di-n-butyl itaconate and bis(2-ethylhexyl) itaconate, are examined using a series of RAFT agents to afford well-defined polymers. The number-average molecular weights of these polymers increase with the monomer conversion while retaining relatively narrow molecular weight distributions. Based on the successful controlled/living polymerization, sequential block copolymerization is subsequently investigated using mono- and di-functional RAFT agents to produce block copolymers with soft poly(itaconate) and hard poly(itaconimide) segments. The properties of the obtained triblock copolymer are evaluated as bio-based acrylic thermoplastic elastomers., (© 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Primary human megakaryocytes, the precursor cells of platelets, are difficult to collect and cultivate. Polymers that enrich these cells without affecting their regulation or function are of interest for basic research as well as for cord blood transplantation purposes since co-transplantation of enriched megakaryocyte concentrates increase the success of stem cell therapy. Herein, polymer microarrays were used for the discovery of substrates for MEG-01 cells, with five polymers identified which selectively bound cells of the megakaryocytic lineage. Flow cytometry and miRNA profiling revealed that immobilisation had only a minor effect on the cellular maturation status, making the identified substrates potential candidates for concentrating megakaryocytes from patients prior to transplantation., (Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The bistable electroactive polymer is a new smart material capable of large strain, rigid-to-rigid actuation. At the rubbery state of the polymer heated to above its glass transition, stable electrically-induced actuation is obtained at strains as large as 150%. Electromechanical instability can be effectively overcome by the formation of interpenetrating polymer networks. An application as a refreshable braille display is demonstrated., (Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Graft copolymers composed of poly(2-methoxyethyl acrylate) are prepared employing controlled radical polymerization techniques. Linear backbones bearing atom transfer radical polymerization (ATRP) initiating sites are obtained by reversible addition-fragmentation chain transfer copolymerization of 2-methoxyethyl acrylate (MEA) and 2-(bromoisobutyryloxy)ethyl methacrylate (Br(i) BuEMA) as well as 2-hydroxyethyl methacrylate and Br(i) BuEMA in a controlled manner . MEA is then grafted from the linear macroinitiators by Cu (I)-mediated ATRP. Fairly high molecular weights (>120 000 Da) and low polydispersity indices (1.17-1.38) are attained. Thermal investigations of the graft copolymers indicate the presence of the freezing bound water, and imply that the materials may exhibit blood compatibility., (Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Unusual self-assembly behavior is observed for a range of hydrophilic homopolymers. This self-assembly behavior is contrary to the expected behavior of such hydrophilic polymers and instead mimics more commonly reported amphiphilic block copolymers. It is proposed that the unique combination of hydrophobic end groups at both the α and ω chain end accounts for this unusual self-assembly behavior. Complex internal polymer micelles are spontaneously formed when hydrophilic homopolymer polyelectrolytes and neutral polymers (with a weight fraction of the hydrophobic end groups <10 wt%) are directly dissolved in water. The homopolymers, poly[2-(diethylamino)ethyl methacrylate], poly(N-isopropylacrylamide), and poly(ethoxyethylacrylate) are synthesized by reversible addition-fragmentation chain-transfer (RAFT) polymerization using S'-1-dodecyl-(S')-(α,α'-dimethyl-α″-acetic acid) trithiocarbonate (DDMAT) and its derivatives as chain transfer agents (CTAs). A range of polyelectrolyte homopolymers with different terminal groups are designed and synthesized, which under acidic aqueous solution direct the self-assembly to form well-defined nanostructures. This assembly behavior was also observed for neutral polymers, and it was determined that the structure of the hydrophobic end groups (and thus choice of RAFT CTA) are very important in facilitating this unusual self-assembly behavior of hydrophilic homopolymers. It is proposed that the functionality of commonly used CTAs such as DDMAT, can affect the solution association of the resultant homopolymers and can in fact afford ABA' type polymers, which can undergo self-assembly to form higher-order nanostructures., (Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

An embedded catalyst for the oxidative dehydration of glycerol, featuring iron oxide (FeO(x)) domains on the surface of an iron orthovanadate (FeVO₄) phase, is developed. Catalytic reactions are conducted in a fixed-bed reactor at 300 °C with a feed composition N₂/O₂/H₂O/glycerol=66.6:1.7:30.3:1.5. Catalytic results show that the catalyst exhibits a better performance than an FeO(x) catalyst prepared by impregnation and than a mixture of FeVO₄ and Fe₂O₃The best yield for acrylic acid was 14 %. The presence of FeO(x) domains on the surface of FeVO₄ catalyzes the oxidation of acrolein to acrylic acid. The catalysts are characterized by a range of techniques. The interaction between the nanometer-sized FeO(x) domains and the FeVO₄ phase is strong enough to stabilize the FeO(x) and retain its high activity. The proximity of the two phases provides an environment for the dehydration of glycerol and the oxidation of acrolein to acrylic acid.

Online preconcentration and separation of analytes using an in situ photopolymerized hexyl acrylate-based monolith stationary phase was evaluated using electrochromatography in capillary format and microchip. The band broadening occurring during the preconcentration process by frontal electrochromatography and during the desorption process by elution electrochromatography was studied. The hexyl acrylate-based monolith provides high retention for neutral analytes allowing the handling of large sample volumes and its structure allows rapid mass transfer, thus reducing the band broadening. For moderately polar analytes such as mono-chlorophenols that are slightly retained in water, it was shown that enrichment factors up to 3500 can be obtained by a hydrodynamic injection of several bed volumes for 120 min under 0.8 MPa with a decrease in efficiency of 50% and a decrease of 30% for the resolution between 2- and 3-chlorophenol. An 8 min preconcentration time allows enrichment factors above 100 for polyaromatic hydrocarbons. The interest of these monoliths when synthesized in microchip is also demonstrated. A 200-fold enrichment was easily obtained for PAHs with only 1 min as preconcentration time, without decrease in efficiency.

We report the synthesis of CdS quantum dot (QD)-poly(acrylate) nanocomposites using a recently developed catalytic system where activators are generated by electron transfer for atom-transfer radical polymerization (ATRP) in a miniemulsion. The QD surface was functionalized with a tris(alkyl)phosphine, previously modified with an ATRP chlorine initiator, and subsequent controlled polymerization was carried out from the functionalized surface of nanoparticles. The final material showed a high homogeneity and the QDs were evenly dispersed. The optical-absorption edge in the visible spectra of the nanocomposites attests the presence of the CdS QDs. Quantum confinement effects were assigned, though a blue shift in relation to the optical spectrum of the initial QDs has been observed.

The development of a new synthetic approach to acrylates based on the formation of alkyl esters of acrylic acids has been studied. A preformed Pd-COOMe moiety is used as a model system to investigate the insertion of an olefin into the Pd--C bond. The fast elimination of acrylate is observed. Density functional calculations support the experimental findings and allow the characterization of transition states along the reaction pathway. The first example of olefin/CO(2) coupling with facile release of ethyl acrylate is also presented.

Despite the large number of publications and patents concerning pH/thermoresponsive polymers, few data are available concerning the preparation of thermoresponsive cross-linked microspheres from preformed polymers. Therefore, N-isopropylacrylamide-co-acrylamide-co-(2-hydroxyethyl acrylate) copolymers were obtained as a new thermoresponsive material with a lower critical solution temperature (LCST) around 36 degrees C, in phosphate buffer at pH 7.4, and with a cross-linkable OH group in their structure. The LCST value was determined both by UV spectroscopy and microcalorimetric analysis. These copolymers were solubilised in acidified aqueous solution below their LCST, dispersed in mineral oil, and transformed into stable microspheres by cross-linking with glutaraldehyde. The thermoresponsive microspheres were characterised by optical and scanning electron microscopy, degree of swelling, and water retention. The pore dimensions of the microspheres and the retention volumes of some drugs and typical compounds were evaluated at different temperatures by liquid chromatography. Indomethacin, as a model drug, was included in the microspheres by the solvent evaporation method. Finally, the influence of temperature and of temperature cycling on drug release was investigated.

A range of zwitterionic acrylic acid derivatives, buffering in the neutral and basic pH ranges, have been synthesized by the Mannich reaction of malonic acid, formaldehyde and a secondary amine. These compounds include 2-(4-morpholinomethyl)propenoic acid pK2 7.59 +/- 0.03 (23 degrees C), 2-[bis(2-hydroxyethyl)aminomethyl]propenoic acid pK2 approximately 8.6 (20 degrees C), 2-[bis(2-hydroxypropyl) aminomethyl]propenoic acid PK2 approximately 8.7 (20 degrees C), 2-[N-(2-hydroxyethyl)-N-methylaminomethyl]propenoic acid pK2 9.22+/-0.08 (22 degrees C), 2-[N-ethyl-N-(2hydroxyethyl)aminomethyl]-propenoic acid pK2 approximately 9.6 (20 degrees C), and 2-[4-(2-carboxyprop-2-enyl)piperazinylmethyl]propenoic acid, which has a sigmoidal buffering profile over the pH range 3-10. These zwitterionic acrylic acid buffers were successfully copolymerized with acrylamide to prepare immobilized pH gradients (IPGs) in the neutral to alkaline portion of the pH range. Bovine erythrocyte carbonic anhydrase isozymes were resolved on a pH 5-8 IPG prepared using 2-[4-(2-carboxyprop-2-enyl)piperazinylmethyl]propenoic acid as the immobilized buffer, and horse heart myoglobin was focused on pH 7.1-8.1 and pH 7.5-7.7 IPGs, using 2-(4-morpholinomethyl)propenoic acid as the immobilized buffer. In both cases the pK 9.3 Immobiline compound was used as the strongly basic titrant. These new compounds, besides possessing more hydrophilic residues than the corresponding commercial basic acrylamido buffers (Immobilines), resist hydrolysis at alkaline pH values.