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Komendová M, Svobodová P, Urban J. Photografting of polymer monoliths by a crosslinking monomer. J Chromatogr A 2020; 1631:461558. [DOI: 10.1016/j.chroma.2020.461558] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Revised: 08/25/2020] [Accepted: 09/16/2020] [Indexed: 01/23/2023]
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Rodriguez-Abetxuko A, Sánchez-deAlcázar D, Muñumer P, Beloqui A. Tunable Polymeric Scaffolds for Enzyme Immobilization. Front Bioeng Biotechnol 2020; 8:830. [PMID: 32850710 PMCID: PMC7406678 DOI: 10.3389/fbioe.2020.00830] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Accepted: 06/29/2020] [Indexed: 12/12/2022] Open
Abstract
The number of methodologies for the immobilization of enzymes using polymeric supports is continuously growing due to the developments in the fields of biotechnology, polymer chemistry, and nanotechnology in the last years. Despite being excellent catalysts, enzymes are very sensitive molecules and can undergo denaturation beyond their natural environment. For overcoming this issue, polymer chemistry offers a wealth of opportunities for the successful combination of enzymes with versatile natural or synthetic polymers. The fabrication of functional, stable, and robust biocatalytic hybrid materials (nanoparticles, capsules, hydrogels, or films) has been proven advantageous for several applications such as biomedicine, organic synthesis, biosensing, and bioremediation. In this review, supported with recent examples of enzyme-protein hybrids, we provide an overview of the methods used to combine both macromolecules, as well as the future directions and the main challenges that are currently being tackled in this field.
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Affiliation(s)
| | | | - Pablo Muñumer
- PolyZymes group, POLYMAT and Department of Applied Chemistry (UPV/EHU), San Sebastián, Spain
| | - Ana Beloqui
- PolyZymes group, POLYMAT and Department of Applied Chemistry (UPV/EHU), San Sebastián, Spain
- Department of Applied Chemistry, University of the Basque Country, San Sebastián, Spain
- IKERBASQUE, Bilbao, Spain
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Lu N, Sticker D, Kretschmann A, Petersen NJ, Kutter JP. A thiol-ene microfluidic device enabling continuous enzymatic digestion and electrophoretic separation as front-end to mass spectrometric peptide analysis. Anal Bioanal Chem 2020; 412:3559-3571. [DOI: 10.1007/s00216-020-02609-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Revised: 03/13/2020] [Accepted: 03/18/2020] [Indexed: 02/07/2023]
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Komendová M, Ribeiro LF, Urban J. Controlling selectivity of polymer-based monolithic stationary phases. J Sep Sci 2019; 42:952-961. [PMID: 30576067 DOI: 10.1002/jssc.201801046] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2018] [Revised: 12/13/2018] [Accepted: 12/14/2018] [Indexed: 12/27/2022]
Abstract
In this work, we aimed to prepare a monolithic capillary column that allowed an isocratic separation of ten dopamine precursors and metabolites in a single run. Segments of five zwitterion sulfobetaine polymer monoliths have been modified by zwitterion phoshorylcholine by using an ultraviolet-initiated two-step photografting. Columns with 0, 33, 50, 66, and 100% of modified length were prepared. Effect of length of the modified segment and mobile phase composition has been tested. All columns provided dual-retention mechanism with reversed-phase retention in highly aqueous mobile phase and hydrophilic interaction mechanism in highly organic mobile phase. The retention mechanism was controlled by the composition of the mobile phase and has been described by a three-parameter model. We have used regression parameters to characterize the retention of analyzed compounds and to study individual pathways of dopamine metabolism. Comprehensive optimization of mobile phase composition allowed to find an optimal composition of the mobile phase and stationary phase surface chemistry arrangement to achieve desired separation. Optimized columns provided an isocratic separation of all tested compounds in less than nine min.
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Affiliation(s)
- Martina Komendová
- Department of Chemistry, Faculty of Science, Masaryk University, Brno, Czech Republic
| | | | - Jiří Urban
- Department of Chemistry, Faculty of Science, Masaryk University, Brno, Czech Republic
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Fresco-Cala B, Carrasco-Correa EJ, Cárdenas S, Herrero-Martínez JM. Carbon nanostructures incorporated on methacrylate monoliths for separation of small molecules by nano-liquid chromatography. Microchem J 2018. [DOI: 10.1016/j.microc.2018.03.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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6
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Liu DM, Chen J, Shi YP. Advances on methods and easy separated support materials for enzymes immobilization. Trends Analyt Chem 2018. [DOI: 10.1016/j.trac.2018.03.011] [Citation(s) in RCA: 150] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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7
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Zhou Q, Wang H, Zhu K, Zhu L, Zhou S, Peng J, Lu X. Effects of ultrasound irradiation on enzymatic hydrolysis of protein and application for the determination of tetracyclines in complex matrices. Drug Test Anal 2017; 9:1586-1593. [PMID: 28262009 DOI: 10.1002/dta.2181] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2017] [Revised: 02/26/2017] [Accepted: 02/28/2017] [Indexed: 11/09/2022]
Abstract
The widespread use of tetracyclines (TCs) in food animals has led to concerns regarding unsafe residue levels in feed, food and manure. The determination of TCs in such matrices suffers from interference by the interactions between proteins and TCs. Three deproteination methods were compared in this study. In contrast with acid deproteination, which caused a large loss of TCs due to the strong adsorption of TCs on protein precipitates, a normal enzymatic hydrolysis was confirmed to have a merit of effectively releasing TCs from protein matrices, but required treatment time as long as 16 h. The adoption of ultrasound irradiation was proposed to shorten the enzymatic hydrolysis time. After investigating the effects of ultrasound power and irradiation time, the conditions of the ultrasound-enhanced enzymatic hydrolysis were optimized as ultrasound power of 100 W and irradiation time of 6 min. The ultrasound-enhanced enzymatic hydrolysis treatment of 6 min yielded recovery of TCs (from protein-containing matrices) as high as that obtained by the normal enzymatic hydrolysis treatment of 16 h. The acceleration effect of ultrasound irradiation was attributed to ultrasound-induced cavitation, which increased exposure of both the functional groups of trypsin and the C-terminal amino acid in the protein that was a cleavage site for trypsin attack. When the ultrasound-enhanced enzymatic hydrolysis method was used to determine TCs in complex matrices, it was found that this new method achieved recoveries of 89.5, 117.7, 110.4 and 100.0% for oxytetracycline, tetracycline, chlortetracycline and doxycycline, being much higher than those (29.6-39.4%) obtained using the common acid deproteination process. Copyright © 2017 John Wiley & Sons, Ltd.
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Affiliation(s)
- Qian Zhou
- Hubei Research Institute of Products Quality Supervision and Inspection, Wuchang District, Wuhan, 430070, PR China.,College of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Hongshan district, Wuhan, 430074, PR China
| | - Hong Wang
- Hubei Research Institute of Products Quality Supervision and Inspection, Wuchang District, Wuhan, 430070, PR China
| | - Kuanzheng Zhu
- Hubei Research Institute of Products Quality Supervision and Inspection, Wuchang District, Wuhan, 430070, PR China
| | - Lihua Zhu
- College of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Hongshan district, Wuhan, 430074, PR China
| | - Shengyin Zhou
- Hubei Research Institute of Products Quality Supervision and Inspection, Wuchang District, Wuhan, 430070, PR China
| | - Jin Peng
- Hubei Research Institute of Products Quality Supervision and Inspection, Wuchang District, Wuhan, 430070, PR China
| | - Xiya Lu
- Hubei Research Institute of Products Quality Supervision and Inspection, Wuchang District, Wuhan, 430070, PR China
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Wouters B, Dapic I, Valkenburg TS, Wouters S, Niezen L, Eeltink S, Corthals GL, Schoenmakers PJ. A cyclic-olefin-copolymer microfluidic immobilized-enzyme reactor for rapid digestion of proteins from dried blood spots. J Chromatogr A 2017; 1491:36-42. [DOI: 10.1016/j.chroma.2017.01.078] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2016] [Revised: 01/19/2017] [Accepted: 01/27/2017] [Indexed: 11/27/2022]
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9
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Combined “post-infiltration, subsequent photochemical cross-linking” and “cross-linking and selective etching” strategies to fabricate nanoporous layer-by-layer assembled multilayers. Colloid Polym Sci 2016. [DOI: 10.1007/s00396-016-3990-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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10
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Devi S, Wu BH, Chu PY, Liu YP, Wu HL, Ho YP. Studying the effect of microwave heating on the digestion process and identification of proteins. Electrophoresis 2016; 38:429-440. [PMID: 27770443 DOI: 10.1002/elps.201600392] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2016] [Revised: 10/06/2016] [Accepted: 10/12/2016] [Indexed: 11/07/2022]
Abstract
The impact of microwave irradiation on the in-solution digestion processes and the detection limit of proteins are systematically studied. Kinetic processes of many peptides produced through the trypsin digestion of various proteins under microwave heating at 50°C were investigated with MALDI-MS. This study also examines the detection limits and digestion completeness of individual proteins under microwave heating at 50°C and at different time intervals (1, 5 and 30 min) using LC-MS. We conclude that if the peptides without missed cleavage dictate the detection limit, conventional digestion will lead to a better detection limit. The detection limit may not differ between the microwave and conventional heating if the peptides with missed cleavage sites and strong intensity are formed at the very early stage (i.e., less than 1 min) and are not further digested throughout the entire digestion process. The digestion of Escherichia coli lysate was compared under conventional and short time (microwave) conditions. The number of proteins identified under conventional heating exceeded that obtained from microwave heating over heating periods less than 5 min. The overall results show that the microwave-assisted digestion is not complete. Although the sequence coverage might be better, the detection limit might be worse than that under conventional heating.
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Affiliation(s)
- Shobha Devi
- Department of Chemistry, National Dong Hwa University, Hualien, Taiwan
| | - Bo-Hung Wu
- Department of Chemistry, National Dong Hwa University, Hualien, Taiwan
| | - Pei-Yu Chu
- Department of Chemistry, National Dong Hwa University, Hualien, Taiwan
| | - Yue-Pei Liu
- Department of Chemistry, National Dong Hwa University, Hualien, Taiwan
| | - Hsin-Lin Wu
- Department of Chemistry, National Dong Hwa University, Hualien, Taiwan
| | - Yen-Peng Ho
- Department of Chemistry, National Dong Hwa University, Hualien, Taiwan
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11
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Lin R, Skandarajah A, Gerver RE, Neira HD, Fletcher DA, Herr AE. A lateral electrophoretic flow diagnostic assay. LAB ON A CHIP 2015; 15:1488-96. [PMID: 25608872 PMCID: PMC4383188 DOI: 10.1039/c4lc01370k] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Immunochromatographic assays are a cornerstone tool in disease screening. To complement existing lateral flow assays (based on wicking flow) we introduce a lateral flow format that employs directed electrophoretic transport. The format is termed a "lateral e-flow assay" and is designed to support multiplexed detection using immobilized reaction volumes of capture antigen. To fabricate the lateral e-flow device, we employ mask-based UV photopatterning to selectively immobilize unmodified capture antigen along the microchannel in a barcode-like pattern. The channel-filling polyacrylamide hydrogel incorporates a photoactive moiety (benzophenone) to immobilize capture antigen to the hydrogel without a priori antigen modification. We report a heterogeneous sandwich assay using low-power electrophoresis to drive biospecimen through the capture antigen barcode. Fluorescence barcode readout is collected via a low-resource appropriate imaging system (CellScope). We characterize lateral e-flow assay performance and demonstrate a serum assay for antibodies to the hepatitis C virus (HCV). In a pilot study, the lateral e-flow assay positively identifies HCV+ human sera in 60 min. The lateral e-flow assay provides a flexible format for conducting multiplexed immunoassays relevant to confirmatory diagnosis in near-patient settings.
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Affiliation(s)
- Robert Lin
- Department of Bioengineering, UC Berkeley, Berkeley, CA 94720 USA.
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12
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Jo H, Theato P. Post-polymerization Modification of Surface-Bound Polymers. CONTROLLED RADICAL POLYMERIZATION AT AND FROM SOLID SURFACES 2015. [DOI: 10.1007/12_2015_315] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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13
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Chung M, Kim D, Herr AE. Polymer sieving matrices in microanalytical electrophoresis. Analyst 2014; 139:5635-54. [DOI: 10.1039/c4an01179a] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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15
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Performance Evaluation of Monolith Based Immobilized Acetylcholinesterase Flow-Through Reactor for Copper(II) Determination with Spectrophotometric Detection. J CHEM-NY 2014. [DOI: 10.1155/2014/757069] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
A monolith based immobilized acetylcholinesterase (AChE) flow-through reactor has been developed for the determination of copper(II) using flow injection spectrophotometric system. The bioreactor was prepared inside a microcapillary column byin situpolymerization of butyl methacrylate, ethylene dimethacrylate, and 2,2-dimethoxy-1,2-diphynyletane-1-one in the presence of 1-decanol, followed by vinyl azlactone functionalization and AChE immobilization. The behavior of AChE before and after being immobilized on the monolith was evaluated by kinetic parameters from Lineweaver and Burk equation. The detection was based on measuring inhibition effect on the enzymatic activity of AChE by copper(II) using Ellman’s reaction with spectrophotometric detection at 410 nm. The linear range of the calibration graph was obtained over the range of 0.02–3.00 mg L−1. The detection limit, defined as 10% inhibition (I10), was found to be 0.04 mg L−1. The repeatability was 3.35 % (n=5) for 1.00 mg L−1of copper(II). The proposed method was applied to the determination of copper(II) in natural water samples with sampling rate of 4 h−1.
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Hassan El-Feky H, Cano-Òdena À, Gumí T. Facile synthesis of porous monolithic membrane microdevice. J Memb Sci 2013. [DOI: 10.1016/j.memsci.2013.03.008] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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17
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Currivan S, Connolly D, Paull B. Production of polymer monolithic capillary columns with integrated gold nano-particle modified segments for on-capillary extraction. Microchem J 2013. [DOI: 10.1016/j.microc.2012.08.007] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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18
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Chang CF, Truong QD, Chen JR. RETRACTED: Graphene as excellent support for rapid and efficient near infrared-assisted triptic proteolysis. Colloids Surf B Biointerfaces 2013; 104:221-8. [DOI: 10.1016/j.colsurfb.2012.11.040] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2012] [Revised: 10/24/2012] [Accepted: 11/13/2012] [Indexed: 11/17/2022]
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19
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Vlakh EG, Tennikova TB. Flow-through immobilized enzyme reactors based on monoliths: II. Kinetics study and application. J Sep Sci 2013; 36:1149-67. [DOI: 10.1002/jssc.201201090] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2012] [Revised: 12/17/2012] [Accepted: 12/17/2012] [Indexed: 11/10/2022]
Affiliation(s)
- Evgenia G. Vlakh
- Institute of Macromolecular Compounds; Russian Academy of Sciences; St. Petersburg Russia
- Faculty of Chemistry; Saint-Petersburg State University; St. Petersburg Russia
| | - Tatiana B. Tennikova
- Institute of Macromolecular Compounds; Russian Academy of Sciences; St. Petersburg Russia
- Faculty of Chemistry; Saint-Petersburg State University; St. Petersburg Russia
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Evaluating the potential nonthermal microwave effects of microwave-assisted proteolytic reactions. J Proteomics 2013; 80:160-70. [DOI: 10.1016/j.jprot.2013.01.005] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2012] [Revised: 01/09/2013] [Accepted: 01/09/2013] [Indexed: 11/18/2022]
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21
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Jia L, Lu Y, Shao J, Liang XJ, Xu Y. Nanoproteomics: a new sprout from emerging links between nanotechnology and proteomics. Trends Biotechnol 2013; 31:99-107. [DOI: 10.1016/j.tibtech.2012.11.010] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2012] [Revised: 11/29/2012] [Accepted: 11/29/2012] [Indexed: 10/27/2022]
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Vlakh EG, Tennikova TB. Flow-through immobilized enzyme reactors based on monoliths: I. Preparation of heterogeneous biocatalysts. J Sep Sci 2013; 36:110-27. [DOI: 10.1002/jssc.201200594] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2012] [Revised: 08/13/2012] [Accepted: 08/13/2012] [Indexed: 11/11/2022]
Affiliation(s)
- Evgenia G. Vlakh
- Institute of Macromolecular Compounds; Russian Academy of Sciences; St. Petersburg Russia
- Faculty of Chemistry; Saint-Petersburg State University; St. Petersburg Russia
| | - Tatiana B. Tennikova
- Institute of Macromolecular Compounds; Russian Academy of Sciences; St. Petersburg Russia
- Faculty of Chemistry; Saint-Petersburg State University; St. Petersburg Russia
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Weed AMK, Dvornik J, Stefancin JJ, Gyapong AA, Svec F, Zajickova Z. Photopolymerized organo-silica hybrid monolithic columns: Characterization of their performance in capillary liquid chromatography. J Sep Sci 2012; 36:270-8. [DOI: 10.1002/jssc.201200760] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2012] [Revised: 09/14/2012] [Accepted: 09/26/2012] [Indexed: 11/12/2022]
Affiliation(s)
| | - Jill Dvornik
- Department of Physical Sciences; Barry University; Miami Shores; FL; USA
| | | | | | - Frantisek Svec
- The Molecular Foundry; E. O. Lawrence Berkeley National Laboratory; Berkeley; CA; USA
| | - Zuzana Zajickova
- Department of Physical Sciences; Barry University; Miami Shores; FL; USA
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Lv Y, Alejandro FM, Fréchet JMJ, Svec F. Preparation of porous polymer monoliths featuring enhanced surface coverage with gold nanoparticles. J Chromatogr A 2012; 1261:121-8. [PMID: 22542442 PMCID: PMC3424317 DOI: 10.1016/j.chroma.2012.04.007] [Citation(s) in RCA: 109] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2012] [Revised: 04/02/2012] [Accepted: 04/03/2012] [Indexed: 11/20/2022]
Abstract
A new approach to the preparation of porous polymer monoliths with enhanced coverage of pore surface with gold nanoparticles has been developed. First, a generic poly(glycidyl methacrylate-co-ethylene dimethacrylate) monolith was reacted with cystamine followed by the cleavage of its disulfide bonds with tris(2-carboxylethyl)phosphine, which liberated the desired thiol groups. Dispersions of gold nanoparticles with sizes varying from 5 to 40 nm were then pumped through the functionalized monoliths. The materials were then analyzed using both energy dispersive X-ray spectroscopy and thermogravimetric analysis. We found that the quantity of attached gold was dependent on the size of nanoparticles, with the maximum attachment of more than 60 wt% being achieved with 40 nm nanoparticles. Scanning electron micrographs of the cross sections of all the monoliths revealed the formation of a non-aggregated, homogenous monolayer of nanoparticles. The surface of the bound gold was functionalized with 1-octanethiol and 1-octadecanethiol, and these monolithic columns were used successfully for the separations of proteins in reversed phase mode. The best separations were obtained using monoliths modified with 15, 20, and 30 nm nanoparticles since these sizes produced the most dense coverage of pore surface with gold.
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Affiliation(s)
- Yongqin Lv
- Department of Chemistry, University of California, Berkeley, CA 94720, USA
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25
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Bremus-Köbberling E, Gillner A, Avemaria F, Réthoré C, Bräse S. Photochemistry with laser radiation in condensed phase using miniaturized photoreactors. Beilstein J Org Chem 2012; 8:1213-8. [PMID: 23019450 PMCID: PMC3458740 DOI: 10.3762/bjoc.8.135] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2012] [Accepted: 06/18/2012] [Indexed: 12/02/2022] Open
Abstract
Miniaturized microreactors enable photochemistry with laser irradiation in flow mode to convert azidobiphenyl into carbazole with high efficiency.
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Affiliation(s)
| | - Arnold Gillner
- Fraunhofer Institute for Laser Technology, Steinbachstrasse 15, D-52074 Aachen, Germany
| | - Frank Avemaria
- Institute of Organic Chemistry, Karlsruhe Institute of Technology, Fritz-Haber-Weg 6, D-76131 Karlsruhe, Germany
| | - Céline Réthoré
- Institute of Organic Chemistry, Karlsruhe Institute of Technology, Fritz-Haber-Weg 6, D-76131 Karlsruhe, Germany
| | - Stefan Bräse
- Institute of Organic Chemistry, Karlsruhe Institute of Technology, Fritz-Haber-Weg 6, D-76131 Karlsruhe, Germany
- Institute of Toxicology and Genetics, Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, D-76344 Eggenstein-Leopoldshafen, Germany
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27
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Valveless gated injection for microfluidic chip-based liquid chromatography system with polymer monolithic column. J Chromatogr A 2012; 1246:123-8. [DOI: 10.1016/j.chroma.2012.03.045] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2011] [Revised: 03/13/2012] [Accepted: 03/16/2012] [Indexed: 11/24/2022]
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28
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Li Y, Aggarwal P, Tolley H, Lee M. Organic Monolith Column Technology for Capillary Liquid Chromatography. ADVANCES IN CHROMATOGRAPHY 2012; 50:237-80. [DOI: 10.1201/b11636-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
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29
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Buck ME, Lynn DM. Azlactone-Functionalized Polymers as Reactive Platforms for the Design of Advanced Materials: Progress in the Last Ten Years. Polym Chem 2012; 3:66-80. [PMID: 29492112 PMCID: PMC5826603 DOI: 10.1039/c1py00314c] [Citation(s) in RCA: 96] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Polymers functionalized with azlactone (or oxazolone) functionality have become increasingly useful for the rapid and modular design of functional materials. Because azlactones can react via ring-opening reactions with a variety of different nucleophilic species (e.g., primary amines, hydroxyl groups, and thiol functionality), azlactone-functionalized materials can serve as convenient 'reactive' platforms for the post-synthesis or post-fabrication introduction of a broad range of chemical functionality to soluble polymers, insoluble supports, and surfaces/interfaces. The last decade has seen an increase in both the number and the variety of reports that exploit the properties and the reactivities of azlactone-functionalized polymers. Here, we highlight recent work from several different laboratories, including our own, toward the design and characterization of azlactone-functionalized polymers, with a particular emphasis on: (i) new synthetic approaches for the preparation of well-defined azlactone-functionalized polymers using living/controlled methods of polymerization, (ii) the design and modular synthesis of side-chain functionalized polymers and block copolymers via post-polymerization modification of azlactone-functionalized polymers, (iii) the development of reactive polymeric supports useful in the contexts of separations and catalysis, and (iv) methods for the fabrication of reactive thin films and other approaches to the immobilization of azlactone functionality on surfaces and interfaces. Examples discussed herein reveal a growing awareness of azlactone functionality as a useful tool for polymer chemists, and highlight several ways that the unique reactivity of these materials can both complement and provide useful alternatives to other reactive polymers currently used to design functional materials.
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Affiliation(s)
- Maren E Buck
- Department of Chemistry, 1101 University Avenue, Madison, WI 53706
| | - David M Lynn
- Department of Chemistry, 1101 University Avenue, Madison, WI 53706
- Department of Chemical and Biological Engineering, 1415 Engineering Drive, University of Wisconsin-Madison, Madison, WI 53706
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Immobilized trypsin on epoxy organic monoliths with modulated hydrophilicity: Novel bioreactors useful for protein analysis by liquid chromatography coupled to tandem mass spectrometry. J Chromatogr A 2011; 1218:8937-45. [DOI: 10.1016/j.chroma.2011.05.059] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2011] [Revised: 05/16/2011] [Accepted: 05/17/2011] [Indexed: 10/18/2022]
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Fan Y, Rubakhin SS, Sweedler JV. Collection of peptides released from single neurons with particle-embedded monolithic capillaries followed by detection with matrix-assisted laser desorption/ionization mass spectrometry. Anal Chem 2011; 83:9557-63. [PMID: 22053721 DOI: 10.1021/ac202338e] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Characterization of the stimulated release of neuropeptides from brain slices and individual cultured neurons requires efficient collection of the releasate from relatively large volumes of physiological saline. Here, several collection approaches are optimized using particle-embedded monolithic capillaries (PEMCs) with poly(stearyl methacrylate-co-ethylene glycol dimethacrylate) monolith acting as a "glue". Two distinct extraction particles, with either pyrrolidone (PY) or ethylenediamine (EDA) as the functional group on polystyrene backbone, have been embedded into capillaries having an inner diameter of 250 μm. The capillaries act as collection devices for sampling neuropeptide release; the collection protocols are described, and the extraction efficiency of the probes are characterized. Specifically, the binding of angiotensin II from a peptide mixture onto the PY and EDA columns was 16 and 28 pmol, respectively, in a volume of 20 μL of saline. The peptides released from these columns have been characterized via matrix-assisted laser desorption/ionization time-of-flight mass spectrometry with low femtomole detection limits. When the PEMC columns were positioned in close proximity to individual neurons and 50 mM KCl was used as the secretagogue, peptides released from individual identified cultured neurons isolated from Aplysia californica were collected and characterized.
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Affiliation(s)
- Yi Fan
- Department of Chemistry, University of Illinois at Urbana-Champaign, Illinois 61801, United States
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Anderson EB, Buchmeiser MR. Catalysts Immobilized on Organic Polymeric Monolithic Supports: From Molecular Heterogeneous Catalysis to Biocatalysis. ChemCatChem 2011. [DOI: 10.1002/cctc.201100086] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Liang Y, Zhu G, Wang T, Zhang X, Liang Z, Zhang L, Zhang Y. Fast preparation of monolithic immobilized pH gradient column by photopolymerization and photografting techniques for isoelectric focusing separation of proteins. Electrophoresis 2011; 32:2911-4. [DOI: 10.1002/elps.201100195] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2011] [Revised: 03/29/2011] [Accepted: 05/06/2011] [Indexed: 11/10/2022]
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Urbanova I, Svec F. Monolithic polymer layer with gradient of hydrophobicity for separation of peptides using two-dimensional thin layer chromatography and MALDI-TOF-MS detection. J Sep Sci 2011; 34:2345-51. [DOI: 10.1002/jssc.201100202] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2011] [Revised: 05/08/2011] [Accepted: 05/08/2011] [Indexed: 11/11/2022]
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Wang H, Duan J, Xu H, Zhao L, Liang Y, Shan Y, Zhang L, Liang Z, Zhang Y. Monoliths with immobilized zirconium ions for selective enrichment of phosphopeptides. J Sep Sci 2011; 34:2113-21. [DOI: 10.1002/jssc.201100168] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2011] [Revised: 04/10/2011] [Accepted: 04/11/2011] [Indexed: 11/11/2022]
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Tretinnikov ON, Pilipenko VV, Firsov SP. Photoinitiated grafting polymerization of acrylic acid onto the surface of polyethylene under pulsed laser radiation. POLYMER SCIENCE SERIES B 2011. [DOI: 10.1134/s1560090411040099] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Namera A, Nakamoto A, Saito T, Miyazaki S. Monolith as a new sample preparation material: Recent devices and applications. J Sep Sci 2011; 34:901-24. [DOI: 10.1002/jssc.201000795] [Citation(s) in RCA: 90] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2010] [Revised: 01/12/2011] [Accepted: 01/15/2011] [Indexed: 11/07/2022]
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Abstract
A novel miniaturized system has been developed for measuring protein-protein interactions in solution with high efficiency and speed, and minimal use of protein. A chromatographic monolith synthesized in a capillary is used in the method to make interaction measurements by self-interaction chromatography (SIC) in a manner that, compared to column methods, is more efficient as well as more readily practicable even if only small amounts of protein are available. The microfluidic monolith requires much less protein for both column synthesis and the chromatographic measurements than a conventional SIC system, and in addition offers improved mass transfer and hence higher chromatographic efficiency than for previous SIC miniaturization systems. Protein self-interactions for catalase as a model protein, quantified by measurement of second virial coefficients, B(22), were determined by SIC and follow trends that are consistent with previously reported values. Different column derivatization conditions were studied in order to optimize the chromatographic behavior of the microfluidic system for SIC measurements. Chromatographic sensitivity can be further increased by using different column synthesis conditions.
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Affiliation(s)
- Cristina Martin
- Department of Chemical Engineering, University of Delaware, Newark, DE 19716, USA
| | - Abraham M. Lenhoff
- Department of Chemical Engineering, University of Delaware, Newark, DE 19716, USA
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Osiri JK, Shadpour H, Witek MA, Soper SA. Integrated multifunctional microfluidics for automated proteome analyses. Top Curr Chem (Cham) 2011; 304:261-94. [PMID: 21678138 DOI: 10.1007/128_2011_152] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Proteomics is a challenging field for realizing totally integrated microfluidic systems for complete proteome processing due to several considerations, including the sheer number of different protein types that exist within most proteomes, the large dynamic range associated with these various protein types, and the diverse chemical nature of the proteins comprising a typical proteome. For example, the human proteome is estimated to have >10(6) different components with a dynamic range of >10(10). The typical processing pipeline for proteomics involves the following steps: (1) selection and/or extraction of the particular proteins to be analyzed; (2) multidimensional separation; (3) proteolytic digestion of the protein sample; and (4) mass spectral identification of either intact proteins (top-down proteomics) or peptide fragments generated from proteolytic digestions (bottom-up proteomics). Although a number of intriguing microfluidic devices have been designed, fabricated and evaluated for carrying out the individual processing steps listed above, work toward building fully integrated microfluidic systems for protein analysis has yet to be realized. In this chapter, information will be provided on the nature of proteomic analysis in terms of the challenges associated with the sample type and the microfluidic devices that have been tested to carry out individual processing steps. These include devices such as those for multidimensional electrophoretic separations, solid-phase enzymatic digestions, and solid-phase extractions, all of which have used microfluidics as the functional platform for their implementation. This will be followed by an in-depth review of microfluidic systems, which are defined as units possessing two or more devices assembled into autonomous systems for proteome processing. In addition, information will be provided on the challenges involved in integrating processing steps into a functional system and the approaches adopted for device integration. In this chapter, we will focus exclusively on the front-end processing microfluidic devices and systems for proteome processing, and not on the interface technology of these platforms to mass spectrometry due to the extensive reviews that already exist on these types of interfaces.
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Affiliation(s)
- John K Osiri
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70817, USA
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Kang QS, Li Y, Xu JQ, Su LJ, Li YT, Huang WH. Polymer monolith-integrated multilayer poly(dimethylsiloxane) microchip for online microextraction and capillary electrophoresis. Electrophoresis 2010; 31:3028-34. [PMID: 20872608 DOI: 10.1002/elps.201000210] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
We reported the in situ synthesis and use of porous polymer monolith (PPM) columns in an integrated multilayer PDMS/glass microchip for microvalve-assisted on-line microextraction and microchip electrophoresis for the first time. Under the control of PDMS microvalves, the grafting of the microchannel surface and in situ photopolymerization of poly(methacrylic acid-co-ethylene glycol dimethacrylate) monolith in a defined zone were successfully achieved. Different factors including the surface grafting, polymerization time, PDMS elastic properties (ratio of oligomer/curing reagent) and UV intensity that affect the monolith synthesis in the PDMS microchannel were investigated and optimized. Dopamine, a model analyte, has been online microextracted, eluted, electrophoresized and electrochemically detected in the microchip, with a mean concentration enrichment factor of 80 (n=3). The results demonstrated that the PPM could be synthesized successfully in the PDMS microchip with a homogeneous structure and excellent mechanical properties. Furthermore, owing to the intrinsic character using PDMS in large-scale integrated microsystems, the implantation of PPM pretreatment units in PDMS microchips would make it possible to deal with complicated analytical processes in a high-throughput way.
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Affiliation(s)
- Qin-Shu Kang
- Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences, Wuhan University, Wuhan, P R China
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Hoffman JM, Ebara M, Lai JJ, Hoffman AS, Folch A, Stayton PS. A helical flow, circular microreactor for separating and enriching "smart" polymer-antibody capture reagents. LAB ON A CHIP 2010; 10:3130-8. [PMID: 20882219 PMCID: PMC3116725 DOI: 10.1039/c004978f] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
We report a mechanistic study of how flow and recirculation in a microreactor can be used to optimize the capture and release of stimuli-responsive polymer-protein reagents on stimuli-responsive polymer-grafted channel surfaces. Poly(N-isopropylacrylamide) (PNIPAAm) was grafted to polydimethylsiloxane (PDMS) channel walls, creating switchable surfaces where PNIPAAm-protein conjugates would adhere at temperatures above the lower critical solution temperature (LCST) and released below the LCST. A PNIPAAm-streptavidin conjugate that can capture biotinylated antibody-antigen targets was first characterized. The conjugate's immobilization and release were limited by mass transport to and from the functionalized PNIPAAm surface. Transport and adsorption efficiencies were dependent on the aggregate size of the PNIPAAm-streptavidin conjugate above the LCST and also were dependent on whether the conjugates were heated in the presence of the stimuli-responsive surface or pre-aggregated and then flowed across the surface. As conjugate size increased, through the addition of non-conjugated PNIPAAm, recirculation and mixing were shown to markedly improve conjugate immobilization compared to diffusion alone. Under optimized conditions of flow and reagent concentrations, approximately 60% of the streptavidin conjugate bolus could be captured at the surface and subsequently successfully released. The kinetic release profile sharpness was also strongly improved with recirculation and helical mixing. Finally, the concentration of protein-polymer conjugates could be achieved by continuous conjugate flow into the heated recirculator, allowing nearly linear enrichment of the conjugate reagent from larger volumes. This capability was shown with anti-p24 HIV monoclonal antibody reagents that were enriched over 5-fold using this protocol. These studies provide insight into the mechanism of smart polymer-protein conjugate capture and release in grafted channels and show the potential of this purification and enrichment module for processing diagnostic samples.
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Wang C, Jemere AB, Harrison DJ. Multifunctional protein processing chip with integrated digestion, solid-phase extraction, separation and electrospray. Electrophoresis 2010; 31:3703-10. [PMID: 20967777 DOI: 10.1002/elps.201000317] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2010] [Revised: 07/16/2010] [Accepted: 07/21/2010] [Indexed: 11/08/2022]
Abstract
We describe a microfluidic device in which integrated tryptic digestion, SPE, CE separation and electrospray ionization for MS are performed. The chip comprised of 10 × 30 μm channels for CE, and two serially connected 150 μm deep, 800 μm wide channels packed with 40 to 60 μm diameter beads, loaded with either immobilized trypsin, reversed-phase packing or both. On-chip digestion of cytochrome c using the trypsin bed showed complete consumption of the protein in 3 min, in contrast to the 2 h required for conventional solution phase tryptic digestion. SPE of 0.25 μg/mL solutions of the peptides leu-enkephalin, angiotensin II and LHRH gave concentration enhancements in the range of 4.4-12, for a ten times nominal volume ratio. A 100 nM cytochrome c sample concentrated 13.3 times on-chip gave a sequence coverage of 85.6%, with recovery values ranging from 41.2 to 106%. The same sample run without SPE showed only five fragment peaks and a sequence coverage of 41.3%. When both on-chip digestion and SPE (13.3 volume ratio concentration enhancement) were performed on 200 nM cytochrome c samples, a sequence coverage of 76.0% and recovery values of 21-105% were observed. Performing on-chip digestion alone on the same sample gave only one significant fragment peak. The above digestion/peptide concentration step was compared to on-chip protein concentration by SPE followed by on-chip digestion with solution phase trypsin. Both procedures gave similar recovery results; however, much larger trypsin autodigestion interference in the latter approach was apparent.
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Affiliation(s)
- Can Wang
- Department of Chemistry, University of Alberta, Edmonton, AB, Canada
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44
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Yao G, Deng C, Zhang X, Yang P. Efficient Tryptic Proteolysis Accelerated by Laser Radiation for Peptide Mapping in Proteome Analysis. Angew Chem Int Ed Engl 2010; 49:8185-9. [DOI: 10.1002/anie.201004152] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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45
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Efficient Tryptic Proteolysis Accelerated by Laser Radiation for Peptide Mapping in Proteome Analysis. Angew Chem Int Ed Engl 2010. [DOI: 10.1002/ange.201004152] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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46
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Non-invasive characterization of stationary phases in capillary flow systems using scanning capacitively coupled contactless conductivity detection (sC4D). Trends Analyt Chem 2010. [DOI: 10.1016/j.trac.2010.04.007] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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47
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Krenkova J, Lacher NA, Svec F. Highly efficient enzyme reactors containing trypsin and endoproteinase LysC immobilized on porous polymer monolith coupled to MS suitable for analysis of antibodies. Anal Chem 2010; 81:2004-12. [PMID: 19186936 DOI: 10.1021/ac8026564] [Citation(s) in RCA: 151] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Capillary enzymatic microreactors containing trypsin and endoproteinase LysC immobilized on a porous polymer monolith have been prepared and used for the characterization and identification of proteins such as cytochrome c, bovine serum albumin, and high-molecular weight human immunoglobulin G. The hydrophilicity of diol functionalities originating from the hydrolyzed poly(glycidyl methacrylate-co-ethylene dimethacrylate) monolith was not sufficient to avoid adsorption of hydrophobic albumin in a highly aqueous mobile phase. Therefore, this monolith was first hydrophilized via photografting of poly(ethylene glycol) methacrylate followed by photografting of a 4-vinyl-2,2-dimethylazlactone to provide the pore surface with reactive functionalities required for immobilization. This new approach reduced the undesired nonspecific adsorption of proteins and peptides and facilitated control of both the enzyme immobilization and protein digestion processes. The enzymatic reactors were coupled off-line with MALDI/TOF MS and/or on-line with ESI/TOF MS. Experimental conditions for digestion were optimized using cytochrome c and bovine serum albumin as model proteins. The optimized reactors were then integrated into a multidimensional system comprised of a monolithic capillary enzyme reactor, an in-line nanoLC separation of peptides using a poly(lauryl methacrylate-co-ethylene dimethacrylate) monolithic column, and ESI/TOF MS. With the use of this system, immunoglobulin G was digested at room temperature in 6 min to an extent similar to that achieved with soluble enzyme at 37 degrees C after 24 h.
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Affiliation(s)
- Jana Krenkova
- The Molecular Foundry, E. O. Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
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48
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Xu Y, Cao Q, Svec F, Fréchet JMJ. Porous polymer monolithic column with surface-bound gold nanoparticles for the capture and separation of cysteine-containing peptides. Anal Chem 2010; 82:3352-8. [PMID: 20302345 PMCID: PMC2875083 DOI: 10.1021/ac1002646] [Citation(s) in RCA: 184] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A new porous polymer monolithic capillary column modified with gold nanoparticles that enables the selective capture of cysteine-containing peptides has been developed to reduce the complexity of peptide mixtures generated in bottom-up proteomic analysis. The column is prepared from a poly(glycidyl methacrylate-co-ethylene dimethacrylate) monolith through reaction of some of its epoxide moieties with cysteamine to afford a monolith rich in surface thiol groups. In situ reduction of chloroauric acid within the column is then used to form gold nanoparticles attached to the surface of the pores of the monolith. This process preserves the excellent hydrodynamic properties of the monolithic column while providing a means to selectively retain cysteine-containing peptides from an analyte due to their high affinity for gold. Release of the retained peptides is subsequently achieved with an excess of 2-mercaptoethanol. The loading capacity determined for l-cysteine using frontal elution is 2.58 mumol/m. Since the gold-thiol link is less stable at elevated temperatures, the adsorption capacity is recovered by washing the column at 80 degrees C for 2 h. While regeneration is easy, the multiplicity of bonds between the monolithic support and the gold nanoparticles prevents their elution even under harsh conditions such as treatment with pure 2-mercaptoethanol or treatment with boiling water for 5 h. Application of the gold modified monolith in tandem with a packed C18 capillary column is demonstrated with baseline separation of a peptide mixture achieved in a two step process. The first involves retention of cysteine-containing peptides in monolith with reversed phase separation of all other peptides, while the retained peptides are released from monolith and separated in the second step.
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Affiliation(s)
- Yan Xu
- College of Chemistry, University of California, Berkeley, California 94720-1460, USA
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49
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Svec F. Porous polymer monoliths: amazingly wide variety of techniques enabling their preparation. J Chromatogr A 2010; 1217:902-24. [PMID: 19828151 PMCID: PMC2829304 DOI: 10.1016/j.chroma.2009.09.073] [Citation(s) in RCA: 423] [Impact Index Per Article: 30.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2009] [Revised: 09/11/2009] [Accepted: 09/28/2009] [Indexed: 10/20/2022]
Abstract
The porous polymer monoliths went a long way since their invention two decades ago. While the first studies applied the traditional polymerization processes at that time well established for the preparation of polymer particles, creativity of scientists interested in the monolithic structures has later led to the use of numerous less common techniques. This review article presents vast variety of methods that have meanwhile emerged. The text first briefly describes the early approaches used for the preparation of monoliths comprising standard free radical polymerizations and includes their development up to present days. Specific attention is paid to the effects of process variables on the formation of both porous structure and pore surface chemistry. Specific attention is also devoted to the use of photopolymerization. Then, several less common free radical polymerization techniques are presented in more detail such as those initiated by gamma-rays and electron beam, the preparation of monoliths from high internal phase emulsions, and cryogels. Living processes including stable free radicals, atom transfer radical polymerization, and ring-opening metathesis polymerization are also discussed. The review ends with description of preparation methods based on polycondensation and polyaddition reactions as well as on precipitation of preformed polymers affording the monolithic materials.
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Affiliation(s)
- Frantisek Svec
- The Molecular Foundry, E. O. Lawrence Berkeley National Laboratory, MS 67R6110, Berkeley, CA 94720-8139, USA.
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50
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Currivan S, Connolly D, Gillespie E, Paull B. Fabrication and characterisation of capillary polymeric monoliths incorporating continuous stationary phase gradients. J Sep Sci 2010; 33:484-92. [DOI: 10.1002/jssc.200900720] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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