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Label-free quantification of peptides in solution by disposable patterned hydrophilic chip based MALDI imaging. CHINESE CHEM LETT 2016. [DOI: 10.1016/j.cclet.2016.02.020] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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Lamberti A, Angelini A, Ricciardi S, Frascella F. A flow-through holed PDMS membrane as a reusable microarray spotter for biomedical assays. LAB ON A CHIP 2015; 15:67-71. [PMID: 25360791 DOI: 10.1039/c4lc01027b] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
We propose the exploitation of a holed-designed poly(dimethyl)siloxane (PDMS) membrane as an innovative microarray spotter. The membrane is fabricated by a simple technological approach and can be reused several times. A good level of reproducibility is found upon spotting fluorescent proteins at different concentrations over large areas.
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Affiliation(s)
- A Lamberti
- Department of Applied Science and Technology - DISAT, Politecnico di Torino, C.so Duca degli Abruzzi 24, 10129 Torino, Italy.
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Luk VN, Fiddes LK, Luk VM, Kumacheva E, Wheeler AR. Digital microfluidic hydrogel microreactors for proteomics. Proteomics 2012; 12:1310-8. [PMID: 22589180 DOI: 10.1002/pmic.201100608] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Proteolytic digestion is an essential step in proteomic sample processing. While this step has traditionally been implemented in homogeneous (solution) format, there is a growing trend to use heterogeneous systems in which the enzyme is immobilized on hydrogels or other solid supports. Here, we introduce the use of immobilized enzymes in hydrogels for proteomic sample processing in digital microfluidic (DMF) systems. In this technique, preformed cylindrical agarose discs bearing immobilized trypsin or pepsin were integrated into DMF devices. A fluorogenic assay was used to optimize the covalent modification procedure for enzymatic digestion efficiency, with maximum efficiency observed at 31 μg trypsin in 2-mm diameter agarose gel discs. Gel discs prepared in this manner were used in an integrated method in which proteomic samples were sequentially reduced, alkylated, and digested, with all sample and reagent handling controlled by DMF droplet operation. Mass spectrometry analysis of the products revealed that digestion using the trypsin gel discs resulted in higher sequence coverage in model analytes relative to conventional homogenous processing. Proof-of-principle was demonstrated for a parallel digestion system in which a single sample was simultaneously digested on multiple gel discs bearing different enzymes. We propose that these methods represent a useful new tool for the growing trend toward miniaturization and automation in proteomic sample processing.
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Affiliation(s)
- Vivienne N Luk
- Department of Chemistry, University of Toronto, Toronto, ON, Canada
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Yeh CH, Tsai SH, Wu LW, Lin YC. Using a co-culture microsystem for cell migration under fluid shear stress. LAB ON A CHIP 2011; 11:2583-90. [PMID: 21695290 DOI: 10.1039/c1lc20113a] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
We have successfully developed a microsystem to co-cultivate two types of cells with a minimum defined gap of 50 μm, and to quantitatively study the impact of fluid shear stress on the mutual influence of cell migration velocity and distance. We used the hydrostatic pressure to seed two different cells, endothelial cells (ECs) and smooth muscle cells (SMCs), on opposite sides of various gap sizes (500 μm, 200 μm, 100 μm, and 50 μm). After cultivating the cells for 12 h and peeling the co-culture microchip from the culture dish, we studied the impacts of gap size on the migration of either cell type in the absence or presence of fluid shear stress (7 dyne cm(-2) and 12 dyne cm(-2)) influence. We found that both gap size and shear stress have profound influence on cell migration. Smaller gap sizes (100 μm and 50 μm) significantly enhanced cell migration, suggesting a requirement of an effective concentration of released factor(s) by either cell type in the gap region. Flow-induced shear stress delayed the migration onset of either cell type in a dose-dependent manner regardless of the gap size. Moreover, shear stress-induced decrease of cell migration becomes evident when the gap size was 500 μm. We have developed a co-culture microsystem for two kinds of cells and overcome the conventional difficulties in observation and mixed culture, and it would have more application for bio-manipulation and tissue repair engineering.
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Affiliation(s)
- Chia-Hsien Yeh
- Department of Engineering Science, National Cheng Kung University, 1 University Road, Tainan, 701, Taiwan, ROC
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Liu L, Toledano R, Danieli T, Zhang JQ, Hu JM, Mandler D. Electrochemically patterning sol–gel structures on conducting and insulating surfaces. Chem Commun (Camb) 2011; 47:6909-11. [DOI: 10.1039/c1cc00007a] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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7
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Hughes AJ, Herr AE. Quantitative enzyme activity determination with zeptomole sensitivity by microfluidic gradient-gel zymography. Anal Chem 2010; 82:3803-11. [PMID: 20353191 DOI: 10.1021/ac100201z] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
We describe a sensitive zymography technique that utilizes an automated microfluidic platform to report enzyme molecular weight, amount, and activity (including k(cat) and K(m)) from dilute protein mixtures. Calf intestinal alkaline phosphatase (CIP) is examined in detail as a model enzyme system, and the method is also demonstrated for horseradish peroxidase (HRP). The 40 min assay has a detection limit of 5 zmol ( approximately 3 000 molecules) of CIP. Two-step pore-limit electrophoresis with enzyme assay (PLENZ) is conducted in a single, straight microchannel housing a polyacrylamide (PA) pore-size gradient gel. In the first step, pore limit electrophoresis (PLE) sizes and pseudoimmobilizes resolved proteins. In the second step, electrophoresis transports both charged and neutral substrates into the PLE channel to the entrapped proteins. Arrival of substrate at the resolved enzyme band generates fluorescent product that reveals enzyme molecular weight against a fluorescent protein ladder. Additionally, the PLENZ zymography assay reports the kinetic properties of CIP in a fully quantitative manner. In contrast to covalent enzyme immobilization, physical pseudoimmobilization of CIP in the PA gel does not significantly reduce its maximum substrate turnover rate. However, an 11-fold increase in the Michaelis constant (over the free solution value) is observed, consistent with diffusional limitations on substrate access to the enzyme active site. PLENZ offers a robust platform for rapid and multiplexed functional analysis of heterogeneous protein samples in drug discovery, clinical diagnostics, and biocatalyst engineering.
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Affiliation(s)
- Alex J Hughes
- Department of Bioengineering, University of California, Berkeley, California 94720, USA
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Matosevic S, Lye GJ, Baganz F. Design and characterization of a prototype enzyme microreactor: quantification of immobilized transketolase kinetics. Biotechnol Prog 2010; 26:118-26. [PMID: 19927318 DOI: 10.1002/btpr.319] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
In this work, we describe the design of an immobilized enzyme microreactor (IEMR) for use in transketolase (TK) bioconversion process characterization. The prototype microreactor is based on a 200-microm ID fused silica capillary for quantitative kinetic analysis. The concept is based on the reversible immobilization of His(6)-tagged enzymes via Ni-NTA linkage to surface derivatized silica. For the initial microreactor design, the mode of operation is a stop-flow analysis which promotes higher degrees of conversion. Kinetics for the immobilized TK-catalysed synthesis of L-erythrulose from substrates glycolaldehyde (GA) and hydroxypyruvate (HPA) were evaluated based on a Michaelis-Menten model. Results show that the TK kinetic parameters in the IEMR (V(max(app)) = 0.1 +/- 0.02 mmol min(-1), K(m(app)) = 26 +/- 4 mM) are comparable with those measured in free solution. Furthermore, the k(cat) for the microreactor of 4.1 x 10(5) s(-1) was close to the value for the bioconversion in free solution. This is attributed to the controlled orientation and monolayer surface coverage of the His(6)-immobilized TK. Furthermore, we show quantitative elution of the immobilized TK and the regeneration and reuse of the derivatized capillary over five cycles. The ability to quantify kinetic parameters of engineered enzymes at this scale has benefits for the rapid and parallel evaluation of evolved enzyme libraries for synthetic biology applications and for the generation of kinetic models to aid bioconversion process design and bioreactor selection as a more efficient alternative to previously established microwell-based systems for TK bioprocess characterization.
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Affiliation(s)
- S Matosevic
- The Advanced Centre for Biochemical Engineering, Department of Biochemical Engineering, University College London, London WC1E 7JE, U.K
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Luk VN, Wheeler AR. A Digital Microfluidic Approach to Proteomic Sample Processing. Anal Chem 2009; 81:4524-30. [PMID: 19476392 DOI: 10.1021/ac900522a] [Citation(s) in RCA: 88] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Affiliation(s)
- Vivienne N. Luk
- Department of Chemistry, University of Toronto, 80 Street George St., Toronto, Ontario M5S 3H6, Canada, Donnelly Centre for Cellular and Biomolecular Research, 160 College Street, Toronto, Ontario M5S 3E1, Canada, and Institute for Biomaterials and Biomedical Engineering, University of Toronto, 164 College Street, Toronto, Ontario M5S 3G9, Canada
| | - Aaron R. Wheeler
- Department of Chemistry, University of Toronto, 80 Street George St., Toronto, Ontario M5S 3H6, Canada, Donnelly Centre for Cellular and Biomolecular Research, 160 College Street, Toronto, Ontario M5S 3E1, Canada, and Institute for Biomaterials and Biomedical Engineering, University of Toronto, 164 College Street, Toronto, Ontario M5S 3G9, Canada
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Bernardino SMSA, Fernandes P, Fonseca LP. A new biocatalyst: Penicillin G acylase immobilized in sol-gel micro-particles with magnetic properties. Biotechnol J 2009; 4:695-702. [DOI: 10.1002/biot.200800287] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Ma B, Zhang G, Qin J, Lin B. Characterization of drug metabolites and cytotoxicity assay simultaneously using an integrated microfluidic device. LAB ON A CHIP 2009; 9:232-8. [PMID: 19107278 DOI: 10.1039/b809117j] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
An integrated microfluidic device was developed for the characterization of drug metabolites and a cytotoxicity assay simultaneously. The multi-layer device was composed of a quartz substrate with embedded separation microchannels and a perforated three-microwell array containing sol-gel bioreactors of human liver microsome (HLM), and two PDMS layers. By aligning the microwell array on the quartz substrate with cell culture chambers on the bottom PDMS layer, drug metabolism studies related to functional units, including metabolite generation, detection and incubation with cultured cells to assess metabolism induced cytotoxicity, were all integrated into the microfluidic device. To validate the feasibility of drug metabolism study on the microfluidic chip, UDP-glucuronosyltransferase (UGT) metabolism of acetaminophen (AP) and its effect on hepG2 cytotoxicity were studied first. Then metabolism based drug-drug interaction between AP and phenytoin (PH), which resulted in increased hepG2 cytotoxicity, was proved on this device. All this demonstrated that the developed microfluidic device could be a potential useful tool for drug metabolism and metabolism based drug-drug interaction research.
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Affiliation(s)
- Bo Ma
- Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian, 116023, China
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SAKAI-KATO K, ISHIKURA K. Integration of Biomolecules into Analytical Systems by Means of Silica Sol-Gel Technology. ANAL SCI 2009; 25:969-78. [DOI: 10.2116/analsci.25.969] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Affiliation(s)
| | - Keiko ISHIKURA
- Division of Drugs, National Institute of Health Sciences
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Kwok A, Arumuganathar S, Irvine S, McEwan JR, Jayasinghe SN. A hybrid bio-jetting approach for directly engineering living cells. Biomed Mater 2008; 3:025008. [DOI: 10.1088/1748-6041/3/2/025008] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Kwon JA, Lee H, Lee KN, Chae K, Lee S, Lee DK, Kim S. High diagnostic accuracy of antigen microarray for sensitive detection of hepatitis C virus infection. Clin Chem 2008; 54:424-8. [PMID: 18223133 DOI: 10.1373/clinchem.2007.090464] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/09/2022]
Abstract
BACKGROUND Hepatitis C virus (HCV) can be transmitted through blood transfusion. Screening ELISA, the most widely used method for HCV diagnosis, sometimes yields false-positive and false-negative results, so a confirmatory test is used. This secondary testing is labor-intensive and expensive, and thus is impractical for massive blood bank screening. Therefore, a new massive screening method with high accuracy is needed for sensitive and specific detection of HCV. METHODS With sol-gel material, we designed novel antigen microarray in 96-well plates for HCV detection. Each individual well was spotted with 4 different HCV antigens. We used this new system to test 154 patient serum samples previously tested for HCV by ELISA (87 HCV positive and 67 HCV negative) (HCV EIA3.0, ABBOTT). We assessed the detection limit of our microarray system with the use of serial 10-fold dilutions of an HCV-positive sample. RESULTS Our microarray assay was reproducible and displayed higher diagnostic accuracy (specificity) (98.78%) than did the ELISA (81.71%). Our method yielded significantly fewer false-positive results than did the ELISA. The detection limit of our assay was 1000 times more sensitive than that of the ELISA. In addition, we found this novel assay technology to be compatible with the currently employed automated methods used for ELISA. CONCLUSION We successfully applied the sol-gel-based protein microarray technology to a screening assay for HCV diagnosis with confirmatory test-level accuracy. This new, inexpensive method will improve the specificity and sensitivity of massive sample diagnosis.
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Affiliation(s)
- Jung-Ah Kwon
- Diagnosis Division, Kuro Korea University Hospital, Seoul, Korea
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Wang H, Meng S, Guo K, Liu Y, Yang P, Zhong W, Liu B. Microfluidic immunosensor based on stable antibody-patterned surface in PMMA microchip. Electrochem commun 2008. [DOI: 10.1016/j.elecom.2008.01.005] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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Kohli N, Worden RM, Lee I. Direct Transfer of Preformed Patterned Bio-Nanocomposite Films on Polyelectrolyte Multilayer Templates. Macromol Biosci 2007; 7:789-97. [PMID: 17541924 DOI: 10.1002/mabi.200700006] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Microarrays containing multiple, nanostructured layers of biological materials would enable high-throughput screening of drug candidates, investigation of protein-mediated cell adhesion, and fabrication of novel biosensors. In this paper, we have examined in detail an approach that allows high-quality microarrays of layered, bionanocomposite films to be deposited on virtually any substrate. The approach uses LBL self-assembly to pre-establish a multilayered structure on an elastomeric stamp, and then uses microCP to transfer the 3-D structure intact to the target surface. For examples, different 3-D patterns containing dendrimers, polyelectrolyte multilayers and two proteins, sADH and sDH, have been fabricated. For the first time, the approach was also extended to create overlaid bionanocomposite patterns and multiple proteins containing patterns. The approach overcomes a problem encountered when using microCP to establish a pattern on the target surface and then building sequential layers on the pattern via LBL self-assembly. Amphiphilic molecules such as proteins and dendrimers tend to adsorb both to the patterned features as well as the underlying substrate, resulting in low-quality patterns. By circumventing this problem, this research significantly extends the range of surfaces and layering constituents that can be used to fabricate 3-D, patterned, bionanocomposite structures. [image in text]
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Affiliation(s)
- Neeraj Kohli
- Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, MI-48824, USA
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Sol–gel process for vegetal cell encapsulation. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2007. [DOI: 10.1016/j.msec.2006.04.010] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Shi M, Peng Y, Yu S, Liu B, Kong J. Site-specific protein immobilization in a microfluidic chip channelvia an IEF-gelation process. Electrophoresis 2007; 28:1587-94. [PMID: 17447236 DOI: 10.1002/elps.200600569] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
A novel strategy for site-specific protein immobilization via combining chip IEF with low-temperature sol-gel technology, called IEF-GEL here, in the channel of a modified poly(methyl methacrylate) (PMMA) microfluidic chip is proposed in this work. The IEF-GEL process involves firstly IEF for homogeneously dissolved protein in PBS containing alumina sol and carrier ampholyte with prearranged pH gradient, and then gelation locally for protein encapsulation. The process and feasibility of proposed IEF-GEL were investigated by EOF measurements, fluorescence microscopic photography, Raman spectrum and further demonstrated by glucose oxidase (GOx) reactors integrated with end-column electrochemical detection. Site-controllable immobilization of protein was realized in a 30 mm long microfluidic chip channel by the strategy to create a approximately 1.7 mm concentrated FITC-BSA band, which leads to great improvement of the elute peak shape, accomplished with remarkably increased sensitivity, approximately 20 times higher than that without IEF-GEL treatment to GOx reactors. The kinetic response of GOx after IEF-GEL treatment was also investigated. The proposed system holds the advantages of IEF and low-temperature sol-gel technologies, i.e. concentrating the protein to be focused and retaining the biological activity for the gel-embedded protein, thus realizes site-specific immobilization of low-concentration protein at nL volume level.
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Affiliation(s)
- Mianhong Shi
- Department of Chemistry, Fudan University, Shanghai, PR China
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Chollet C, Lazare S, Labrugère C, Guillemot F, Bareille R, Durrieu M. RGD peptides micro-patterning on poly(ethylene terephthalate) surfaces. Ing Rech Biomed 2007. [DOI: 10.1016/j.rbmret.2007.03.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Lewandowski AT, Yi H, Luo X, Payne GF, Ghodssi R, Rubloff GW, Bentley WE. Protein assembly onto patterned microfabricated devices through enzymatic activation of fusion pro-tag. Biotechnol Bioeng 2007; 99:499-507. [PMID: 17625789 DOI: 10.1002/bit.21580] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
We report a versatile approach for covalent surface-assembly of proteins onto selected electrode patterns of pre-fabricated devices. Our approach is based on electro-assembly of the aminopolysaccharide chitosan scaffold as a stable thin film onto patterned conductive surfaces of the device, which is followed by covalent assembly of the target protein onto the scaffold surface upon enzymatic activation of the protein's "pro-tag." For our demonstration, the model target protein is green fluorescent protein (GFP) genetically fused with a pentatyrosine pro-tag at its C-terminus, which assembles onto both two-dimensional chips and within fully packaged microfluidic devices in situ and under flow. Our surface-assembly approach enables spatial selectivity and orientational control under mild experimental conditions. We believe that our integrated approach harnessing genetic manipulation, in situ enzymatic activation, and electro-assembly makes it advantageous for a wide variety of bioMEMS and biosensing applications that require facile "biofunctionalization" of microfabricated devices.
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Affiliation(s)
- Angela T Lewandowski
- Department of Chemical and Biomolecular Engineering, University of Maryland, College Park, Maryland, USA
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Suh IB, Ryu SW, Lee Y, Hur DS, Chung C, Chang JK, Lim CS. Development of a New Blood Typing Kit Using the Microfluidics Separation Technique. THE KOREAN JOURNAL OF HEMATOLOGY 2007. [DOI: 10.5045/kjh.2007.42.4.392] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Affiliation(s)
- In Bum Suh
- Department of Laboratory Medicine, Kangwon National University College of Medicine, Chuncheon, Korea
| | - Sook Won Ryu
- Department of Laboratory Medicine, Kangwon National University College of Medicine, Chuncheon, Korea
| | - Yongku Lee
- Digital Bio Technology Co, Seoul, Korea
- Seoul National University School of Mechanical and Aerospace Engineering, Seoul, Korea
| | | | | | - Jun Keun Chang
- Digital Bio Technology Co, Seoul, Korea
- Seoul National University School of Electrical Engineering and Computer Science, Seoul, Korea
| | - Chae Seung Lim
- Department of Laboratory Medicine, Korea University College of Medicine, Seoul, Korea
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A designer ormosil gel for preparation of sensitive immunosensor for carcinoembryonic antigen based on simple direct electron transfer. Electrochem commun 2006. [DOI: 10.1016/j.elecom.2006.08.026] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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Zhang Q, Xu JJ, Chen HY. Patterning microbeads inside poly(dimethylsiloxane) microfluidic channels and its application for immobilized microfluidic enzyme reactors. Electrophoresis 2006; 27:4943-51. [PMID: 17117456 DOI: 10.1002/elps.200600024] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
We propose a convenient and reliable approach for immobilizing microbeads on poly(dimethylsiloxane) (PDMS) microchips. It is built upon a simple fabrication procedure of PDMS chip through directly printing the master with an office laser printer which was described in our previous work (J. Chromatogr. A 2005, 1089, 270-275). On the printed toners used as the positive relief of the master, microbeads were immobilized by a thermal treatment and then transferred to the surface of the microchip by direct molding of the prepolymer on the master. With this approach, the region-selective immobilization of microbeads and the fabrication of PDMS microchips can be accomplished at the same time. Then, using these microbeads as supports, further modification with enzyme was achieved. Surface characteristics of the microbeads-modified PDMS microchannels were investigated with scanning electron microscope, atomic force microscope, and inverse fluorescence microscope. The electrokinetic properties of the native PDMS and the modified PDMS chips were also compared. Based on this approach, an immobilized glucose oxidase (GOD) reactor was constructed and the reaction using glucose as substrate was studied. All these experiments aim to show that the proposed approach may have a good potential in the study of biochemistry and other related areas.
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Affiliation(s)
- Qing Zhang
- The Key Laboratory of Analytical Chemistry for Life Science (MOE), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, China
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Wu HL, Yang PY, Fan GR, Tian YP, Lu HJ, Jin H. Sol-gel-derived Poly(dimethylsiloxane) Enzymatic Reactor for Microfluidic Peptide Mapping. CHINESE J CHEM 2006. [DOI: 10.1002/cjoc.200690172] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Huang Y, Shan W, Liu B, Liu Y, Zhang Y, Zhao Y, Lu H, Tang Y, Yang P. Zeolite nanoparticle modified microchip reactor for efficient protein digestion. LAB ON A CHIP 2006; 6:534-9. [PMID: 16572216 DOI: 10.1039/b517590a] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
An enzymatic microreactor has been fabricated based on the poly(methyl methacrylate) (PMMA) microchchip surface-modified with zeolite nanoparticles. By introducing the silanol functional groups, the surface of PMMA microchannel has been successfully modified with silicalite-1 nanoparticle for the first time due to its large external surface area and high dispersibility in solutions. Trypsin can be stably immobilized in the microchannel to form a bioreactor using silica sol-gel matrix. The immobilization of enzyme can be realized with a stable gel network through a silicon-oxygen-silicon bridge via tethering to those silanol groups, which has been investigated by scanning electron microscopy and microchip capillary electrophoresis with laser-induced fluorescence detection. The maximum proteolytic rate constant of the immobilized trypsin is measured to be about 6.6 mM s(-1). Using matrix assisted laser desorption and ionization time-of-flight mass spectrometry, the proposed microreactor provides an efficient digestion of cytochrome c and bovine serum albumin at a fast flow rate of 4.0 microL min(-1), which affords a very short reaction time of less than 5 s.
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Affiliation(s)
- Yi Huang
- Department of Chemistry, Fudan University, Shanghai 200433, People's Republic of China
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Urban PL, Goodall DM, Bruce NC. Enzymatic microreactors in chemical analysis and kinetic studies. Biotechnol Adv 2006; 24:42-57. [PMID: 16055295 DOI: 10.1016/j.biotechadv.2005.06.001] [Citation(s) in RCA: 171] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2005] [Accepted: 06/03/2005] [Indexed: 11/27/2022]
Abstract
The fields of application of microreactors are becoming wider every year. A considerable number of papers have been published recently reporting successful application of enzymatic microreactors in chemistry and biochemistry. Most are devices with enzymes immobilized on beads or walls of microfluidic channels, whilst some use dissolved enzymes to run a reaction in the microfluidic system. Apart from model systems, mostly with glucose oxidase, horseradish peroxidase and alkaline phosphatase, the principal fields of application of microreactors are tryptic digestion of proteins and polymerase chain reaction in automated analyses of proteomic and genetic material, respectively. Enzymatic microreactors also facilitate characterization of enzyme activity as a function of substrate concentration, and enable fast screening of new biocatalysts and their substrates. They may constitute key parts of lab-on-a-chip and muTAS, assisting the analysis of biomolecules. This review provides systematic coverage of examples of reports on enzymatic microreactors published recently, as well as relevant older papers.
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Affiliation(s)
- Pawel L Urban
- Department of Chemistry, University of York, Heslington, UK
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Kato M, Sakai-Kato K, Toyo'oka T. Silica sol-gel monolithic materials and their use in a variety of applications. J Sep Sci 2005. [DOI: 10.1002/jssc.200500225] [Citation(s) in RCA: 92] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Tsai HC, Doong RA. Simultaneous determination of pH, urea, acetylcholine and heavy metals using array-based enzymatic optical biosensor. Biosens Bioelectron 2005; 20:1796-804. [PMID: 15681196 DOI: 10.1016/j.bios.2004.07.008] [Citation(s) in RCA: 113] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2004] [Revised: 06/28/2004] [Accepted: 07/09/2004] [Indexed: 11/23/2022]
Abstract
An array-based optical biosensor for the simultaneous analysis of multiple samples in the presence of unrelated multi-analytes was fabricated. Urease and acetylcholinesterase (AChE) were used as model enzymes and were co-entrapped with the sensing probe, FITC-dextran, in the sol-gel matrix to measure pH, urea, acetylcholine (ACh) and heavy metals (enzyme inhibitors). Environmental and biological samples spiked with metal ions were also used to evaluate the application of the array biosensor to real samples. The biosensor exhibited high specificity in identifying multiple analytes. No obvious cross-interference was observed when a 50-spot array biosensor was used for simultaneous analysis of multiple samples in the presence of multiple analytes. The sensing system can determine pH over a dynamic range from 4 to 8.5. The limits of detection (LODs) of 2.5-50 microM with a dynamic range of 2-3 orders of magnitude for urea and ACh measurements were obtained. Moreover, the urease-encapsulated array biosensor was used to detect heavy metals. The analytical ranges of Cd(II), Cu(II), and Hg(II) were between 10 nM and 100 mM. When real samples were spiked with heavy metals, the array biosensor also exhibited potential effectiveness in screening enzyme inhibitors.
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Affiliation(s)
- Hsiao-chung Tsai
- Department of Atomic Science, National Tsing Hua University, 101, Sec. 2, Kuang Fu Road, Hsinchu 30013, Taiwan
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31
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Kohli N, Worden RM, Lee I. Intact transfer of layered, bionanocomposite arrays by microcontact printing. Chem Commun (Camb) 2005:316-8. [PMID: 15645022 DOI: 10.1039/b406430e] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A novel approach is presented that allows high-quality, 3D patterned bionanocomposite layered films to be constructed on substrates whose surface properties are incompatible with existing self-assembly methods.
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Affiliation(s)
- Neeraj Kohli
- Department of Chemical Engineering & Materials Science, Michigan State University, East Lansing, Michigan 48824, USA
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32
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Jindal R, Cramer SM. On-chip electrochromatography using sol–gel immobilized stationary phase with UV absorbance detection. J Chromatogr A 2004; 1044:277-85. [PMID: 15354449 DOI: 10.1016/j.chroma.2004.05.065] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A chromatography column on a chip was fabricated by immobilizing reversed-phase stationary phase particles (5 microm, C4) using sol-gel technology. Channels were fabricated in quartz using photolithography and wet etching. Localization of the stationary phase was achieved by immobilizing the stationary phase at the desired location in the separation channel prior to bonding of the cover plate. Cross channel design was employed for gated injection. An optical fiber setup was developed for carrying out on-chip UV absorbance detection. The effective optical path length was theoretically determined for the trapezoidal shaped channel and the result was shown to match closely with the experimentally determined value. The effect of applied voltage on velocity was evaluated using thiourea as an unretained marker. Separation performance of the stationary phase was demonstrated by separation of three peptides (Trp-Ala, Leu-Trp and Trp-Trp) under isocratic chromatographic conditions.
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Affiliation(s)
- Rohit Jindal
- Howard P. Isermann Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy, NY 12180, USA
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33
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Srinivasan A, Bach H, Sherman DH, Dordick JS. Bacterial P450-catalyzed polyketide hydroxylation on a microfluidic platform. Biotechnol Bioeng 2004; 88:528-35. [PMID: 15459906 DOI: 10.1002/bit.20285] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The incorporation of a multicomponent, cofactor-dependant P450 into a microfluidic biochip is demonstrated. The PikC hydroxylase Streptomyces venezuelae was incorporated into a PDMS-based microfluidic channel. The enzyme was immobilized to Ni-NTA agarose beads via in situ attachment following the addition of the beads to the microchannel. The enzyme loading was approximately 6 microg per mg of beads resulting in a microchannel loading of 10.7 mg/mL. This high enzyme loading enabled the rapid hydroxylation of the macrolide YC-17 to methymycin and neomethymycin in about equal amounts with a conversion of >90% at a flow rate of 70 nL/min. This high reactivity allowed rapid hydroxylation reactions to be performed with short residence times, which is critical for complex enzymes with limited inherent stability.
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Affiliation(s)
- Aravind Srinivasan
- Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy, New York 12180, USA
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34
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Yoon JY, Garrell RL. Preventing Biomolecular Adsorption in Electrowetting-Based Biofluidic Chips. Anal Chem 2003; 75:5097-5102. [PMID: 27669630 DOI: 10.1021/ac0342673] [Citation(s) in RCA: 156] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Electrowetting-on-dielectric (EWOD) is a new method for moving liquids in biofluidic chips through electrical modification of the surface hydrophobicity. EWOD-based devices are reconfigurable, have low power requirements, and can handle neutral and charged analytes, as well as particulates. We show that biomolecular adsorption in EWOD is minimized by limiting the time during which no potential is applied and through choice of solution pH and electrode polarity. The same approach may be useful for controlling biomolecular adsorption in other applications of hydrophobic dielectric materials. These results demonstrate the feasibility of implementing EWOD for fluid actuation in biofluidic chips.
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Affiliation(s)
- Jeong-Yeol Yoon
- Department of Chemistry and Biochemistry, and Biomedical Engineering Interdepartmental Program, University of California, Los Angeles, California 90095-1569
| | - Robin L Garrell
- Department of Chemistry and Biochemistry, and Biomedical Engineering Interdepartmental Program, University of California, Los Angeles, California 90095-1569
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35
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Zhang T, Tian B, Kong J, Yang P, Liu B. A sensitive mediator-free tyrosinase biosensor based on an inorganic–organic hybrid titania sol–gel matrix. Anal Chim Acta 2003. [DOI: 10.1016/s0003-2670(03)00758-x] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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36
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Park SS, Joo HS, Cho SI, Kim MS, Kim YK, Kim BG. Multi-step reactions on microchip platform using nitrocellulose membrane reactor. BIOTECHNOL BIOPROC E 2003. [DOI: 10.1007/bf02942275] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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37
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Lee MY, Srinivasan A, Ku B, Dordick JS. Multienzyme catalysis in microfluidic biochips. Biotechnol Bioeng 2003; 83:20-8. [PMID: 12740929 DOI: 10.1002/bit.10642] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The attachment of enzymes to glass microfluidic channels has been achieved using a highly reactive poly(maleic anhydride-alt-alpha-olefin) (PMA)-based coating that is supplied to the microchannel in a toluene solution. The PMA reacts with 3-aminopropyltriethoxysilane groups linked to the glass surface to form a matrix that enables additional maleic anhydride groups to react with free amino groups on enzymes to give a mixed covalent-noncovalent immobilization support. Using a simple T-channel microfluidic design, with reaction channel dimensions of 200 microm wide (at the center), 15 microm deep, and 30 mm long giving a reaction volume of 90 nL, soybean peroxidase (SBP) was attached at an amount up to 0.6 microg/channel. SBP-catalyzed oxidation of p-cresol was performed in aqueous buffer (with 20% [v/v], dimethylformamide) containing H(2)O(2), with microfluidic transport enabled by electroosmotic flow (EOF). Michaelis-Menten kinetics were obtained with K(m) and V(max) values of 0.98 mM and 0.21 micromol H(2)O(2) converted/mg SBP per minute, respectively. These values are nearly identical to nonimmobilized SBP kinetics in aqueous-DMF solutions in 20-microL volumes in 384-well plates and 5-mL reaction volumes in 20-mL scintillation vials. These results indicate that SBP displays intrinsically native activity even in the immobilized form at the microscale, and further attests to the mild immobilization conditions afforded by PMA. Bienzymic and trienzymic reactions were also performed in the microfluidic biochip. Specifically, a combined Candida antarctica lipase B-SBP bienzymic system was used to convert tolyl acetate into poly(p-cresol), and an invertase-glucose oxidase SBP trienzymic system was used to take sucrose and generate H(2)O(2) for SBP-catalyzed synthesis of poly(p-cresol).
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Affiliation(s)
- Moo-Yeal Lee
- Department of Chemical Engineering, Rensselaer Polytechnic Institute, 103 Ricketts Building, Troy, New York 12180, USA
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38
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Srinivasan A, Wu X, Lee MY, Dordick JS. Microfluidic peroxidase biochip for polyphenol synthesis. Biotechnol Bioeng 2003; 81:563-9. [PMID: 12514805 DOI: 10.1002/bit.10499] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
An enzyme-containing microfluidic biochip has been developed for the oxidative polymerization of phenols. The biochip consists of a simple T-junction with two feed reservoirs 20 mm apart and a microreaction channel 30 mm long. The channel is 15 microm deep and 200 microm wide at the center, giving a reaction volume of 90 nL. The biochip was fabricated using conventional photolithographic methods on a glass substrate etched using a HF-based solution. Fluid transport was enabled using electroosmotic flow. Soybean peroxidase was used as the phenol oxidizing catalyst, and in the presence of p-cresol and H(2)O(2), essentially complete conversion of the H(2)O(2) (the limiting substrate) occurred in the microchannel at a flow rate of ca. 290 nL/min. Thus, peroxidase was found to be intrinsically active even upon dramatic scale-down as achieved in microfluidic reactors. These results were extended to a series of phenols, thereby demonstrating that the microfluidic peroxidase reactor may have application in high-throughput screening of phenolic polymerization reactions for use in phenolic resin synthesis. Finally, rapid growth of poly(p-cresol) on the walls of the microreaction channel could be performed in the presence of higher H(2)O(2) concentrations. This finding suggests that solution-phase peroxidase catalysis can be used in the controlled deposition of polymers on the walls of microreactors.
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Affiliation(s)
- Aravind Srinivasan
- Department of Chemical Engineering, Rensselaer Polytechnic Institute, Troy, New York 12180, USA
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39
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Davies R, Bartholomeusz DA, Andrade J. Personal sensors for the diagnosis and management of metabolic disorders. IEEE ENGINEERING IN MEDICINE AND BIOLOGY MAGAZINE : THE QUARTERLY MAGAZINE OF THE ENGINEERING IN MEDICINE & BIOLOGY SOCIETY 2003; 22:32-42. [PMID: 12683060 DOI: 10.1109/memb.2003.1191447] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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40
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Abstract
Technological advances in miniaturization have found a niche in biology and signal the beginning of a new revolution. Most of the attention and advances have been made with DNA chips yet a lot of progress is being made in the use of other biomolecules and cells. A variety of reviews have covered only different aspects and technologies but leading to the shared terminology of "biochips." This review provides a basic introduction and an in-depth survey of the different technologies and applications involving the use of non-DNA molecules such as proteins and cells. The review focuses on microarrays and microfluidics, but also describes some cellular systems (studies involving patterning and sensor chips) and nanotechnology. The principles of each technology including parameters involved in biochip design and operation are outlined. A discussion of the different biological and biomedical applications illustrates the significance of biochips in biotechnology.
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Affiliation(s)
- Jocelyn H Ng
- IMI Consulting GmbH, Auf dem Amtshof 3, 30938 Burgwedel, Germany.
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41
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Drevon GF, Danielmeier K, Federspiel W, Stolz DB, Wicks DA, Yu PC, Russell AJ. High-activity enzyme-polyurethane coatings. Biotechnol Bioeng 2002; 79:785-94. [PMID: 12209801 DOI: 10.1002/bit.10334] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The synthesis of water-borne polyurethane coatings in the presence of diisopropylfluorophosphatase (DFPase, E.C. 3.8.2.1) enabled the irreversible attachment of the enzyme to the polymeric matrix. The distribution of immobilized DFPase as well as activity retention are homogeneous within the coating. The resulting enzyme-containing coating (ECC) film hydrolyzes diisopropylfluorophosphate (DFP) in buffered media at high rates, retaining approximately 39% intrinsic activity. Decreasing ECC hydrophilicity, via the use of a less hydrophilic polyisocyanate during polymerization, significantly enhanced the intrinsic activity of the ECC. DFPase-ECC has biphasic deactivation kinetics, where the initial rapid deactivation of DFPase-ECC leads to the formation of a hyperstable and active form of enzyme.
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Affiliation(s)
- Géraldine F Drevon
- Department of Chemical and Petroleum Engineering, University of Pittsburgh, 1249 Benedum Hall, Pennsylvania 15261, USA
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42
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Dordick JS, Khosla C. Engineering of molecular and cellular biocatalysts: selected contributions by James E. Bailey. Biotechnol Bioeng 2002; 79:490-5. [PMID: 12209820 DOI: 10.1002/bit.10404] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
James (Jay) E. Bailey was a pioneer in biotechnology and biochemical engineering. During his 30 years in academia he made seminal contributions to many fields of chemical engineering science, including catalysis and reaction engineering, bioprocess engineering, mathematical modeling of cellular processes, recombinant DNA technology, enzyme engineering, and metabolic engineering. This article celebrates some of his contributions to the engineering of molecular and cellular biocatalysts, and identifies the influence he had on current and future research in biotechnology.
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Affiliation(s)
- Jonathan S Dordick
- Department of Chemical Engineering, Rensselaer Polytechnic Institute, Troy, New York 12180-3590, USA.
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43
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Park CB, Clark DS. Sol-gel encapsulated enzyme arrays for high-throughput screening of biocatalytic activity. Biotechnol Bioeng 2002; 78:229-35. [PMID: 11870613 DOI: 10.1002/bit.10238] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
We developed versatile low-cost arrays of sol-gel-encapsulated enzymes (referred to as solzymes) suitable for repeated assays of bioactivity or enzyme inhibition. Sol-gel microstructures containing active enzymes were stabilized on glass at moderate pH and room temperature without harsh calcination. A multi-well bilayer of polydimethylsiloxane was used to support the solzyme array and contain the reaction medium. Each of the 147 microwells has a working volume of 5 muL and contains 50 mug of immobilized enzyme. The solzyme arrays maintained high activity through repeated applications and exhibited superior thermostability compared to soluble enzymes. Among the enzymes used were lipases, glucose oxidase, and horseradish peroxidase. Twenty different lipases and proteases were also used to prepare a hydrolase array, for which bromthymol blue served as a generic indicator of activity. The relative activities of the encapsulated hydrolases correlated closely with those of the soluble hydrolases, illustrating that sol-gel encapsulation preserved the hierarchy of enzyme activity. The development of solzyme arrays paves the way to higher throughput screening of diverse proteins and enzymes, including those that are available only in trace amounts.
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Affiliation(s)
- Chan B Park
- Department of Chemical Engineering, University of California, Berkeley, California 94720, USA
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44
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Abstract
Recent advances in chip-based separation of proteins provide methods that are faster and more convenient than conventional gel electrophoresis. Rapid and automated protein sizing on a chip is at the commercial stage and first attempts have been made to perform two-dimensional separation on a chip. Numerous designs have been described to interface a microfluidic chip to a mass spectrometer. Impressive integration efforts are demonstrated by the ability to perform on-chip trypsin digestion, separation and injection into a mass spectrometer with a single device.
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Affiliation(s)
- Stephane Mouradian
- Caliper Technologies Corp., 605 Fairchild Drive, Mountain View, California 94043, USA.
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