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Mortelmans T, Marty B, Kazazis D, Padeste C, Li X, Ekinci Y. Three-Dimensional Microfluidic Capillary Device for Rapid and Multiplexed Immunoassays in Whole Blood. ACS Sens 2024; 9:2455-2464. [PMID: 38687557 PMCID: PMC11129352 DOI: 10.1021/acssensors.4c00153] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2024] [Revised: 04/11/2024] [Accepted: 04/16/2024] [Indexed: 05/02/2024]
Abstract
In this study, we demonstrate whole blood immunoassays using a microfluidic device optimized for conducting rapid and multiplexed fluorescence-linked immunoassays. The device is capable of handling whole blood samples without any preparatory treatment. The three-dimensional channels in poly(methyl methacrylate) are designed to passively load bodily fluids and, due to their linearly tapered profile, facilitate size-dependent immobilization of biofunctionalized particles. The channel geometry is optimized to allow for the unimpeded flow of cellular constituents such as red blood cells (RBCs). Additionally, to make the device easier to operate, the biofunctionalized particles are pretrapped in a first step, and the channel is dried under vacuum, after which it can be loaded with the biological sample. This novel approach and design eliminated the need for traditionally laborious steps such as filtering, incubation, and washing steps, thereby substantially simplifying the immunoassay procedures. Moreover, by leveraging the shallow device dimensions, we show that sample loading to read-out is possible within 5 min. Our results also show that the presence of RBCs does not compromise the sensitivity of the assays when compared to those performed in a pure buffer solution. This highlights the practical adaptability of the device for simple and rapid whole-blood assays. Lastly, we demonstrate the device's multiplexing capability by pretrapping particles of different sizes, each functionalized with a different antigen, thus enabling the performance of multiplexed on-chip whole-blood immunoassays, showcasing the device's versatility and effectiveness toward low-cost, simple, and multiplexed sensing of biomarkers and pathogens directly in whole blood.
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Affiliation(s)
- Thomas Mortelmans
- Laboratory for X-ray Nanoscience and Technologies, 5232 Villigen, Switzerland
- Swiss Nanoscience Institute, University of Basel, 4056 Basel, Switzerland
| | - Balz Marty
- Laboratory for X-ray Nanoscience and Technologies, 5232 Villigen, Switzerland
| | - Dimitrios Kazazis
- Laboratory for X-ray Nanoscience and Technologies, 5232 Villigen, Switzerland
| | - Celestino Padeste
- Laboratory of Nanoscale Biology, Paul Scherrer Institute, 5232 Villigen, Switzerland
| | - Xiaodan Li
- Laboratory of Biomolecular Research, Paul Scherrer Institute, 5232 Villigen, Switzerland
| | - Yasin Ekinci
- Laboratory for X-ray Nanoscience and Technologies, 5232 Villigen, Switzerland
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2
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Kemas AM, Zandi Shafagh R, Taebnia N, Michel M, Preiss L, Hofmann U, Lauschke VM. Compound Absorption in Polymer Devices Impairs the Translatability of Preclinical Safety Assessments. Adv Healthc Mater 2024; 13:e2303561. [PMID: 38053301 PMCID: PMC11469150 DOI: 10.1002/adhm.202303561] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2023] [Indexed: 12/07/2023]
Abstract
Organotypic and microphysiological systems (MPS) that can emulate the molecular phenotype and function of human tissues, such as liver, are increasingly used in preclinical drug development. However, despite their improved predictivity, drug development success rates have remained low with most compounds failing in clinical phases despite promising preclinical data. Here, it is tested whether absorption of small molecules to polymers commonly used for MPS fabrication can impact preclinical pharmacological and toxicological assessments and contribute to the high clinical failure rates. To this end, identical devices are fabricated from eight different MPS polymers and absorption of prototypic compounds with different physicochemical properties are analyzed. It is found that overall absorption is primarily driven by compound hydrophobicity and the number of rotatable bonds. However, absorption can differ by >1000-fold between polymers with polydimethyl siloxane (PDMS) being most absorptive, whereas polytetrafluoroethylene (PTFE) and thiol-ene epoxy (TEE) absorbed the least. Strikingly, organotypic primary human liver cultures successfully flagged hydrophobic hepatotoxins in lowly absorbing TEE devices at therapeutically relevant concentrations, whereas isogenic cultures in PDMS devices are resistant, resulting in false negative safety signals. Combined, these results can guide the selection of MPS materials and facilitate the development of preclinical assays with improved translatability.
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Affiliation(s)
- Aurino M. Kemas
- Department of Physiology and PharmacologyKarolinska InstitutetStockholm17177Sweden
| | - Reza Zandi Shafagh
- Department of Physiology and PharmacologyKarolinska InstitutetStockholm17177Sweden
- Dr. Margarete Fischer‐Bosch Institute of Clinical Pharmacology70376StuttgartGermany
- University of Tuebingen72074TuebingenGermany
- Division of Micro‐ and NanosystemsKTH Royal Institute of TechnologyStockholm10044Sweden
| | - Nayere Taebnia
- Department of Physiology and PharmacologyKarolinska InstitutetStockholm17177Sweden
| | - Maurice Michel
- Department of Oncology and PathologyScience for Life LaboratoryKarolinska InstitutetStockholm17165Sweden
| | - Lena Preiss
- Department of Physiology and PharmacologyKarolinska InstitutetStockholm17177Sweden
- Department of Drug Metabolism and Pharmacokinetics (DMPK)Merck KGaA64293DarmstadtGermany
| | - Ute Hofmann
- Dr. Margarete Fischer‐Bosch Institute of Clinical Pharmacology70376StuttgartGermany
| | - Volker M. Lauschke
- Department of Physiology and PharmacologyKarolinska InstitutetStockholm17177Sweden
- Dr. Margarete Fischer‐Bosch Institute of Clinical Pharmacology70376StuttgartGermany
- University of Tuebingen72074TuebingenGermany
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3
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Wang X, Ji F, Jia L. Chimeric AQP4-based immunosorbent for highly-specific removal of AQP4-IgG from blood. J Chromatogr A 2024; 1717:464701. [PMID: 38310704 DOI: 10.1016/j.chroma.2024.464701] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2023] [Revised: 01/26/2024] [Accepted: 01/30/2024] [Indexed: 02/06/2024]
Abstract
Anti-aquaporin-4 autoantibodies (AQP4-IgG) are implicated in the pathogenesis of neuromyelitis optica spectrum disorders (NMOSD), and their removal from the blood circulation is considered to be an effective method for acute treatment. An ideal extracorporeal AQP4-IgG removal system should have high specificity, which means that it can selectively remove AQP4-IgG without affecting normal immunoglobulins. However, the conventional tryptophan immobilized column lacks sufficient specificity and cannot achieve this goal. In this study, we successfully prepared a fusion protein chimeric AQP4, which consists of the complete antigenic epitopes of human AQP4 and the constant region of scaffold protein DARPin. Chimeric AQP4 was expressed and purified from Escherichia coli, and then immobilized on agarose gel as a ligand for selective capture of AQP4-IgG immunosorbent. The prepared immunosorbent had a theoretical maximum adsorption capacity of 20.48 mg/g gel estimated by Langmuir isotherm. In vitro plasma perfusion tests demonstrated that the chimeric AQP4 coupled adsorbent had remarkable adsorption performance, and could eliminate more than 85 % of AQP4-IgG under the gel-to-plasma ratio of 1:50. Moreover, it exhibited high specificity because other human plasma proteins were not adsorbed in the dynamic adsorption experiment. These results suggest that the chimeric AQP4 coupled immunosorbent can provide a new approach for specific immunoadsorption (IA) treatment of NMOSD.
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Affiliation(s)
- Xiaofei Wang
- MOE Key Laboratory of Bio-Intelligent Manufacturing, School of Bioengineering, Dalian University of Technology, Dalian, Liaoning 116023, China; Liaoning Key Laboratory of Molecular Recognition and Imaging, School of Bioengineering, Dalian University of Technology, Dalian, Liaoning 116023, China
| | - Fangling Ji
- MOE Key Laboratory of Bio-Intelligent Manufacturing, School of Bioengineering, Dalian University of Technology, Dalian, Liaoning 116023, China; Liaoning Key Laboratory of Molecular Recognition and Imaging, School of Bioengineering, Dalian University of Technology, Dalian, Liaoning 116023, China.
| | - Lingyun Jia
- MOE Key Laboratory of Bio-Intelligent Manufacturing, School of Bioengineering, Dalian University of Technology, Dalian, Liaoning 116023, China; Liaoning Key Laboratory of Molecular Recognition and Imaging, School of Bioengineering, Dalian University of Technology, Dalian, Liaoning 116023, China.
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Koyagura SS, Majarikar V, Takehara H, Ichiki T. Experimental Evaluation and Modeling of Adsorption Phenomena of Nanoliposomes on Poly(dimethylsiloxane) Surfaces. J PHOTOPOLYM SCI TEC 2021. [DOI: 10.2494/photopolymer.34.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
| | - Virendra Majarikar
- Department of Materials Engineering, School of Engineering, The University of Tokyo
| | - Hiroaki Takehara
- Department of Materials Engineering, School of Engineering, The University of Tokyo
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Yu F, Goh YT, Li H, Chakrapani NB, Ni M, Xu GL, Hsieh TM, Toh YC, Cheung C, Iliescu C, Yu H. A vascular-liver chip for sensitive detection of nutraceutical metabolites from human pluripotent stem cell derivatives. BIOMICROFLUIDICS 2020; 14:034108. [PMID: 32509050 PMCID: PMC7255812 DOI: 10.1063/5.0004286] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Accepted: 05/14/2020] [Indexed: 05/07/2023]
Abstract
Human pluripotent stem cell (hPSC) is a great resource for generating cell derivatives for drug efficiency testing. Metabolites of nutraceuticals can exert anti-inflammatory effects on blood vessels. However, the concentration of nutraceutical metabolites produced in hPSC-derived hepatocytes (hPSC-HEPs) is usually low. To enable the detection of these metabolites under the in vitro environment, we have developed a co-culture model consisting of parallel co-culture chambers and a recirculating microfluidic system with minimum fluid volume, optimal cell culture environment. The model allows cells to be exposed continuously to nutraceutical metabolites. In this perfused culturing model, hPSC-derived endothelial cells and hPSC-HEPs are co-cultured without physical contact. When an anti-inflammatory nutraceutical, quercetin, was administrated to the co-culture, higher levels of quercetin metabolites were detected on-chip compared with static control. We further induced inflammation with Interleukin-1β in the co-culture model and measured interleukin 8 (IL-8) generation. The IL-8 level was suppressed more significantly by quercetin metabolites in the perfusion co-culture, as compared to static culture. This is due to enhanced metabolites production on-chip. This microfluidic co-culture model enables in vitro screening of nutraceuticals using hPSC-derived cells.
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Affiliation(s)
| | | | - Huan Li
- Institute of Bioengineering and Nanotechnology, A*STAR, The Nanos, #04-01, 31 Biopolis Way, Singapore 138669
| | | | - Ming Ni
- School of Biological Sciences and Engineering, Yachay Tech University, Hacienda San José s/n, San Miguel de Urcuquí 100105, Ecuador
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Prada J, Cordes C, Harms C, Lang W. Design and Manufacturing of a Disposable, Cyclo-Olefin Copolymer, Microfluidic Device for a Biosensor †. SENSORS (BASEL, SWITZERLAND) 2019; 19:E1178. [PMID: 30866583 PMCID: PMC6427612 DOI: 10.3390/s19051178] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Revised: 02/26/2019] [Accepted: 03/01/2019] [Indexed: 12/20/2022]
Abstract
This contribution outlines the design and manufacturing of a microfluidic device implemented as a biosensor for retrieval and detection of bacteria RNA. The device is fully made of Cyclo-Olefin Copolymer (COC), which features low auto-fluorescence, biocompatibility and manufacturability by hot-embossing. The RNA retrieval was carried on after bacteria heat-lysis by an on-chip micro-heater, whose function was characterized at different working parameters. Carbon resistive temperature sensors were tested, characterized and printed on the biochip sealing film to monitor the heating process. Off-chip and on-chip processed RNA were hybridized with capture probes on the reaction chamber surface and identification was achieved by detection of fluorescence tags. The application of the mentioned techniques and materials proved to allow the development of low-cost, disposable albeit multi-functional microfluidic system, performing heating, temperature sensing and chemical reaction processes in the same device. By proving its effectiveness, this device contributes a reference to show the integration potential of fully thermoplastic devices in biosensor systems.
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Affiliation(s)
- Jorge Prada
- Institut für Mikrosensoren, -Aktoren und -Systeme, Universität Bremen, 28359 Bremen, Germany.
| | - Christina Cordes
- Bremerhavener Institut für Angewandte Molekularbiologie, Hochschule Bremerhaven, 27568 Bremerhaven, Germany.
| | - Carsten Harms
- Bremerhavener Institut für Angewandte Molekularbiologie, Hochschule Bremerhaven, 27568 Bremerhaven, Germany.
| | - Walter Lang
- Institut für Mikrosensoren, -Aktoren und -Systeme, Universität Bremen, 28359 Bremen, Germany.
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Liu C, Deb S, Ferreira VS, Xu E, Baumgart T. Kinetics of PTEN-mediated PI(3,4,5)P3 hydrolysis on solid supported membranes. PLoS One 2018; 13:e0192667. [PMID: 29447222 PMCID: PMC5813967 DOI: 10.1371/journal.pone.0192667] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2017] [Accepted: 01/26/2018] [Indexed: 11/18/2022] Open
Abstract
Phosphatidylinositides play important roles in cellular signaling and migration. Phosphatidylinositol-3,4,5-trisphosphate (PI(3,4,5)P3) is an important phosphatidylinositide because it acts as a secondary messenger to trigger cell movement and proliferation. A high level of PI(3,4,5)P3 at the plasma membrane is known to contribute to tumorigenesis. One key enzyme that regulates PI(3,4,5)P3 levels at the plasma membrane is phosphatase and tensin homologue deleted on chromosome 10 (PTEN), which dephosphorylates PI(3,4,5)P3 through hydrolysis to form phosphatidylinositol-4,5-bisphosphate (PI(4,5)P2). It has been reported that PI(4,5)P2 is involved in positive feedback in the PI(3,4,5)P3 hydrolysis by PTEN. However, how PI(3,4,5)P3 dephosphorylation by PTEN is regulated, is still under debate. How other PI(3,4,5)P3-binding proteins affect the dephosphorylation kinetics catalyzed by PTEN also remains unclear. Here, we develop a fluorescent-protein biosensor approach to study how PI(3,4,5)P3 dephosphorylation is regulated by PTEN as well as its membrane-mediated feedback mechanisms. Our observation of sigmoidal kinetics of the PI(3,4,5)P3 hydrolysis reaction supports the notion of autocatalysis in PTEN function. We developed a kinetic model to describe the observed reaction kinetics, which allowed us to i) distinguish between membrane-recruitment and allosteric activation of PTEN by PI(4,5)P2, ii) account for the influence of the biosensor on the observed reaction kinetics, and iii) demonstrate that all of these mechanisms contribute to the kinetics of PTEN-mediated catalysis.
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Affiliation(s)
- Chun Liu
- Department of Chemistry, School of Arts & Sciences, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Sanghamitra Deb
- Department of Chemistry, School of Arts & Sciences, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Vinicius S Ferreira
- Department of Chemistry, School of Arts & Sciences, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Eric Xu
- Department of Chemistry, School of Arts & Sciences, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Tobias Baumgart
- Department of Chemistry, School of Arts & Sciences, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
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8
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Chen X, Leary TF, Maldarelli C. Transport of biomolecules to binding partners displayed on the surface of microbeads arrayed in traps in a microfluidic cell. BIOMICROFLUIDICS 2017; 11:014101. [PMID: 28096941 PMCID: PMC5218969 DOI: 10.1063/1.4973247] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2016] [Accepted: 12/13/2016] [Indexed: 05/15/2023]
Abstract
Arrays of probe molecules integrated into a microfluidic cell are utilized as analytical tools to screen the binding interactions of the displayed probes against a target molecule. These assay platforms are useful in enzyme or antibody discovery, clinical diagnostics, and biosensing, as their ultraminiaturized design allows for high sensitivity and reduced consumption of reagents and target. We study here a platform in which the probes are first grafted to microbeads which are then arrayed in the microfluidic cell by capture in a trapping course. We examine a course which consists of V-shaped, half-open enclosures, and study theoretically and experimentally target mass transfer to the surface probes. Target binding is a two step process of diffusion across streamlines which convect the target over the microbead surface, and kinetic conjugation to the surface probes. Finite element simulations are obtained to calculate the target surface concentration as a function of time. For slow convection, large diffusive gradients build around the microbead and the trap, decreasing the overall binding rate. For rapid convection, thin diffusion boundary layers develop along the microbead surface and within the trap, increasing the binding rate to the idealized limit of untrapped microbeads in a channel. Experiments are undertaken using the binding of a target, fluorescently labeled NeutrAvidin, to its binding partner biotin, on the microbead surface. With the simulations as a guide, we identify convective flow rates which minimize diffusion barriers so that the transport rate is only kinetically determined and measure the rate constant.
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Affiliation(s)
- Xiaoxiao Chen
- Department of Chemical Engineering, Benjamin Levich Institute, City College of the City University of New York , New York, New York 10031, USA
| | - Thomas F Leary
- Department of Chemical Engineering, Benjamin Levich Institute, City College of the City University of New York , New York, New York 10031, USA
| | - Charles Maldarelli
- Department of Chemical Engineering, Benjamin Levich Institute, City College of the City University of New York , New York, New York 10031, USA
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9
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Song Q. Protein adsorption in microengraving immunoassays. SENSORS 2015; 15:26236-50. [PMID: 26501282 PMCID: PMC4634505 DOI: 10.3390/s151026236] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Revised: 10/01/2015] [Accepted: 10/09/2015] [Indexed: 11/29/2022]
Abstract
Microengraving is a novel immunoassay forcharacterizing multiple protein secretions from single cells. During the immunoassay, characteristic diffusion and kinetic time scales τD and τK determine the time for molecular diffusion of proteins secreted from the activated single lymphocytes and subsequent binding onto the glass slide surface respectively. Our results demonstrate that molecular diffusion plays important roles in the early stage of protein adsorption dynamics which shifts to a kinetic controlled mechanism in the later stage. Similar dynamic pathways are observed for protein adsorption with significantly fast rates and rapid shifts in transport mechanisms when C0* is increased a hundred times from 0.313 to 31.3. Theoretical adsorption isotherms follow the trend of experimentally obtained data. Adsorption isotherms indicate that amount of proteins secreted from individual cells and subsequently captured on a clean glass slide surface increases monotonically with time. Our study directly validates that protein secretion rates can be quantified by the microengraving immunoassay. This will enable us to apply microengraving immunoassays to quantify secretion rates from 104–105 single cells in parallel, screen antigen-specific cells with the highest secretion rate for clonal expansion and quantitatively reveal cellular heterogeneity within a small cell sample.
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Affiliation(s)
- Qing Song
- Chemical and Biomolecular Engineering, New York University Polytechnic School of Engineering, 6 Metro Tech Center, Brooklyn, NY 11201, USA.
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10
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Ghodbane M, Kulesa A, Yu HH, Maguire TJ, Schloss RR, Ramachandran R, Zahn JD, Yarmush ML. Development of a low-volume, highly sensitive microimmunoassay using computational fluid dynamics-driven multiobjective optimization. MICROFLUIDICS AND NANOFLUIDICS 2015; 18:199-214. [PMID: 25691853 PMCID: PMC4327895 DOI: 10.1007/s10404-014-1416-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Immunoassays are one of the most versatile and widely performed biochemical assays and, given their selectivity and specificity, are used in both clinical and research settings. However, the high cost of reagents and relatively large sample volumes constrain the integration of immunoassays into many applications. Scaling the assay down within microfluidic devices can alleviate issues associated with reagent and sample consumption. However, in many cases a new device is designed and empirically optimized for each specific analyte, a costly and time consuming approach. In this paper, we report the development of a microfluidic bead-based immunoassay which, using antibody coated microbeads, can potentially detect any analyte or combination of analytes for which antibody coated microbeads can be generated. We also developed a computational reaction model and optimization algorithm that can be used to optimize the device for any analyte. We applied this technique to develop a low volume IL-6 immunoassay with high sensitivity (358 fM, 10 pg/mL) and a large dynamic range (4 orders of magnitude). This device design and optimization technique can be used to design assays for any protein with an available antibody and can be used with a large number of applications including biomarker discovery, temporal in vitro studies using a reduced number of cells and reagents, and analysis of scarce biological samples in animal studies and clinical research settings.
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Affiliation(s)
- Mehdi Ghodbane
- Department of Biomedical Engineering, Rutgers, The State University of New Jersey, 599 Taylor Road, Piscataway, New Jersey 08854, USA
| | - Anthony Kulesa
- Department of Biomedical Engineering, Rutgers, The State University of New Jersey, 599 Taylor Road, Piscataway, New Jersey 08854, USA
| | - Henry H. Yu
- Department of Biomedical Engineering, Rutgers, The State University of New Jersey, 599 Taylor Road, Piscataway, New Jersey 08854, USA
| | - Tim J. Maguire
- Department of Biomedical Engineering, Rutgers, The State University of New Jersey, 599 Taylor Road, Piscataway, New Jersey 08854, USA
| | - Rene R. Schloss
- Department of Biomedical Engineering, Rutgers, The State University of New Jersey, 599 Taylor Road, Piscataway, New Jersey 08854, USA
| | - Rohit Ramachandran
- Department of Chemical and Biochemical Engineering, Rutgers, The State University of New Jersey, 98 Brett Road, Piscataway, NJ 08854, USA
| | - Jeffrey D. Zahn
- Department of Biomedical Engineering, Rutgers, The State University of New Jersey, 599 Taylor Road, Piscataway, New Jersey 08854, USA
| | - Martin L. Yarmush
- Department of Biomedical Engineering, Rutgers, The State University of New Jersey, 599 Taylor Road, Piscataway, New Jersey 08854, USA
- Center for Engineering in Medicine/Surgical Services, Massachusetts General Hospital, 51 Blossom Street, Boston, MA, 02114, USA
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Leary TF, Manafirasi S, Maldarelli C. Mass transfer in the biomolecular binding of a target against probe molecules on the surface of microbeads sequestered in wells in a microfluidic cell. LAB ON A CHIP 2015; 15:459-77. [PMID: 25408192 DOI: 10.1039/c4lc01185f] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Diagnostic tools which screen the binding interactions of a protein target against a display of biomolecular probes to identify molecules which bind the target are central to cell proteomic studies, and to diagnostic assays. Here, we study a microfluidic design for screening interactions in which the probe molecules are hosted on microbeads sequestered in wells arranged at the bottom of a microfluidic flow channel. Assays are undertaken by streaming an analyte solution with a fluorescently labelled target through the cell, and identifying the fluorescing beads. Numerical simulations are first constructed for the analyte flow over the microbeads in the well array, and the increase in the target concentration on the microbead surface. The binding profile is expressed as a function of the ratio of the convective to the diffusive transport rates (Peclet number or Pe), and the ratio of the kinetic to the diffusive rates (Damkohler number, Da). For any Pe, as Da becomes small enough, the transport is determined by the intrinsic kinetic binding rate. As Pe increases, a thin concentration boundary layer develops over the top surface of the microbead because of the convective flow, and target binds more rapidly. However, the relatively stagnant layers of liquid in the well provide a diffusion barrier which slows the target transport, and for any Da and Pe the transport is slower than equivalent patches of probes arranged on the channel wall. Experiments are also undertaken at high Pe, using the binding of fluorescently labelled NeutrAvidin as a target to probes of its binding partner, biotin, on the microbead surface. The binding profile is compared to the simulations to measure the kinetic rate constant, and this comparison shows that the transport in the cell is not kinetically limited because of the diffusion barriers created by the stagnant liquid layer in the well. Simulations and experiments on microbeads which are only partially recessed in the well demonstrate an increase in the mass transfer rate as more of the microbead surface intersects the flow and the diffusion limitation due to the stagnant layer of liquid surrounding the bottom part of the microbead is minimized.
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Affiliation(s)
- Thomas F Leary
- Levich Institute and Department of Chemical Engineering, The City College of the City University of New York, New York, New York 10031, USA.
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12
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Kechadi M, Faure M, Sotta B, Gamby J. Investigating the Kinetics of Antibody Adsorption onto Polyethylene Terephthalate (PET) Modified with Gold Nanoparticles in Flow Microchannel. J Flow Chem 2014. [DOI: 10.1556/jfc-d-13-00025] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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13
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Li P. Quantitative heterogeneous immunoassays in protein modified polydimethylsiloxane microfluidic channels for rapid detection of disease biomarkers. Methods Mol Biol 2013; 949:335-47. [PMID: 23329452 DOI: 10.1007/978-1-62703-134-9_21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/10/2023]
Abstract
Conventional detection of disease biomarkers employs techniques such as lateral-flow assays or central laboratory-based enzyme-linked immunosorbent assays (ELISA). Miniaturization and performance improvement of such traditional immunoassays using microfluidic technologies has proved promising in producing rapid, sensitive and automated next-generation immunosensors for quantitative diagnoses in the point-of-care setting. In this article a poly(dimethylsiloxane) (PDMS)-based immunosensor is presented for rapid detection of C-reactive protein. PDMS is selected in part because of the vast popularity of using PDMS as a material for microfluidic devices and in part because of the challenge of obtaining a stable surface coating with PDMS for immunosensing applications. Practical procedures for fabrication, surface modification, and preservation of the microfluidic immuno-chips as well as detailed descriptions of performing the microfluidic heterogeneous assay are presented.
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Affiliation(s)
- Peng Li
- Department of Mechanical, Industrial and Systems Engineering, University of Rhode Island, Kingston, RI, USA.
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14
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Wu CC, Yang DJ. A label-free impedimetric DNA sensing chip integrated with AC electroosmotic stirring. Biosens Bioelectron 2013; 43:348-54. [DOI: 10.1016/j.bios.2012.12.041] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2012] [Revised: 11/29/2012] [Accepted: 12/13/2012] [Indexed: 10/27/2022]
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15
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Ren L, Wang JC, Liu W, Tu Q, Liu R, Wang X, Xu J, Wang Y, Zhang Y, Li L, Wang J. An enzymatic immunoassay microfluidics integrated with membrane valves for microsphere retention and reagent mixing. Biosens Bioelectron 2012; 35:147-154. [DOI: 10.1016/j.bios.2012.02.034] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2011] [Revised: 02/14/2012] [Accepted: 02/16/2012] [Indexed: 01/12/2023]
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Yamazoe H. Fabrication of protein micropatterns using a functional substrate with convertible protein-adsorption surface properties. J Biomed Mater Res A 2011; 100:362-9. [DOI: 10.1002/jbm.a.33279] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2011] [Revised: 09/01/2011] [Accepted: 09/14/2011] [Indexed: 11/08/2022]
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17
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Kinetic analyses and performance of a colloidal magnetic nanoparticle based immunoassay dedicated to allergy diagnosis. Anal Bioanal Chem 2011; 400:3395-407. [DOI: 10.1007/s00216-011-5021-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2011] [Revised: 04/12/2011] [Accepted: 04/12/2011] [Indexed: 11/26/2022]
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18
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Salim M, McArthur SL, Vaidyanathan S, Wright PC. Towards proteomics-on-chip: The role of the surface. ACTA ACUST UNITED AC 2011; 7:101-15. [DOI: 10.1039/c005236a] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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19
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Abstract
This article describes two kinds of "Cell Programmable Assay" (CPA) chips that utilize passive pumping for the culture and autonomous staining of cells to simply common protocols. One is a single timer channel CPA (sCPA) chip that has one timer channel and one main channel containing a cell culture chamber. The sCPA is used to culture and stain cells using Hoechst nuclear staining dye (a 2 step staining process). The other is a dual timer channel CPA (dCPA) chip that has two timer channels and one main channel with a chamber for cell culture. The dCPA is used here to culture, fix, permeablize, and stain cells using DAPI. The additional timer channel of the dCPA chip allows for automation of 3 steps. The CPA chips were successfully evaluated using HEK 293 cells. In addition, we provide a simplified equation for tuning or redesigning CPA chips to meet the needs of a variety of protocols that may require different timings. The equation is easy to use as it only depends upon the dimensions of microchannel and the volume of the reagent drops. The sCPA and dCPA chips can be readily modified to apply to a wide variety of common cell culture methods and procedures.
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Affiliation(s)
- Jongil Ju
- Department of Biomedical Engineering & Wisconsin Institutes for Medical Research, University of Wisconsin-Madison, Madison, WI 53705, USA
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20
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Magnetic track array for efficient bead capture in microchannels. Anal Bioanal Chem 2009; 395:747-57. [DOI: 10.1007/s00216-009-3006-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2009] [Revised: 07/20/2009] [Accepted: 07/23/2009] [Indexed: 10/20/2022]
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21
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Lee BS, Lee JN, Park JM, Lee JG, Kim S, Cho YK, Ko C. A fully automated immunoassay from whole blood on a disc. LAB ON A CHIP 2009; 9:1548-55. [PMID: 19458861 DOI: 10.1039/b820321k] [Citation(s) in RCA: 191] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
A portable, disc-based, and fully automated enzyme-linked immuno-sorbent assay (ELISA) system is developed to test infectious diseases from whole blood. The innovative laser irradiated ferrowax microvalves and centrifugal microfluidics were utilized for the full integration of microbead-based suspension ELISA assays on a disc starting from whole blood. The concentrations of the antigen and the antibody of Hepatitis B virus (HBV), HBsAg and Anti-HBs respectively, were measured using the lab-on-a-disc (LOD). All the necessary reagents are preloaded on the disc and the total process of the plasma separation, incubation with target specific antigen or antibody coated microbeads, multiple steps of washing, enzyme reaction with substrates, and the absorbance detection could be finished within 30 minutes. Compared to the conventional ELISA, the operation time was dramatically reduced from over 2 hours to less than 30 minutes while the limit of detection was kept similar; e.g. the limit of detection of Anti-HBs tests were 8.6 mIU mL(-1) and 10 mIU mL(-1) for the disc-based and the conventional ELISA respectively.
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Affiliation(s)
- Beom Seok Lee
- Bio & Health Group, Samsung Advanced Institute of Technology, P.O. Box 111, Suwon, 440-600, Korea.
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22
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Salim M, Wright PC, McArthur SL. Studies of electroosmotic flow and the effects of protein adsorption in plasma‐polymerized microchannel surfaces. Electrophoresis 2009; 30:1877-87. [DOI: 10.1002/elps.200800619] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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23
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Warrick JW, Murphy WL, Beebe DJ. Screening the cellular microenvironment: a role for microfluidics. IEEE Rev Biomed Eng 2008; 1:75-93. [PMID: 20190880 DOI: 10.1109/rbme.2008.2008241] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
The cellular microenvironment is an increasingly discussed topic in cell biology as it has been implicated in the progression of cancer and the maintenance of stem cells. The microenvironment of a cell is an organized combination of extracellular matrix (ECM), cells, and interstitial fluid that influence cellular phenotype through physical, mechanical, and biochemical mechanisms. Screening can be used to map combinations of cells and microenvironments to phenotypic outcomes in a way that can help develop more predictive in vitro models and to better understand phenotypic mechanisms from a systems biology perspective. This paper examines microenvironmental screening in terms of outcomes and benefits, key elements of the screening process, challenges for implementation, and a possible role for microfluidics as the screening platform. To assess microfluidics for use in microenvironmental screening, examples and categories of micro-scale and microfluidic technology are highlighted. Microfluidic technology shows promise for simultaneous control of multiple parameters of the microenvironment and can provide a base for scaling advanced cell-based experiments into automated high-throughput formats.
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Affiliation(s)
- Jay W Warrick
- Department of Biomedical Engineering, University of Wisconsin, Madison, WI 53706-1609, USA
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24
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Costantino S, McQuinn CG, Kennedy TE, Wiseman PW. Fabrication of protein gradients for cell culture using a miniature squeegee. ACTA ACUST UNITED AC 2008; 70:1192-5. [PMID: 17597222 DOI: 10.1016/j.jbbm.2007.05.013] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2007] [Revised: 05/25/2007] [Accepted: 05/29/2007] [Indexed: 11/15/2022]
Abstract
We present a straightforward method to create spatial gradients of substrate bound protein for live cell studies using only mechanical parts. Protein concentration gradients on a micron scale can be fabricated in several minutes for a relatively low cost using a method that is generally applicable to any protein and substrate combination. We describe the details of the device construction, and provide examples of mammalian cells grown on substrates patterned with protein concentration gradients using this technique.
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Affiliation(s)
- Santiago Costantino
- McGill Program in NeuroEngineering, Department of Physics, McGill University, Montréal, Québec, Canada.
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25
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Ji, Zhang Y, Zhou X, Kong J, Tang Y, Liu B. Enhanced Protein Digestion through the Confinement of Nanozeolite-Assembled Microchip Reactors. Anal Chem 2008; 80:2457-63. [DOI: 10.1021/ac702218v] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Ji
- Department of Chemistry, Fudan University, Shanghai 200433, China
| | - Yahong Zhang
- Department of Chemistry, Fudan University, Shanghai 200433, China
| | - Xiaoqin Zhou
- Department of Chemistry, Fudan University, Shanghai 200433, China
| | - Jilie Kong
- Department of Chemistry, Fudan University, Shanghai 200433, China
| | - Yi Tang
- Department of Chemistry, Fudan University, Shanghai 200433, China
| | - Baohong Liu
- Department of Chemistry, Fudan University, Shanghai 200433, China
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26
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Nevill JT, Cooper R, Dueck M, Breslauer DN, Lee LP. Integrated microfluidic cell culture and lysis on a chip. LAB ON A CHIP 2007; 7:1689-95. [PMID: 18030388 DOI: 10.1039/b711874k] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
We present an integrated microfluidic cell culture and lysis platform for automated cell analysis that improves on systems which require multiple reagents and manual procedures. Through the combination of previous technologies developed in our lab (namely, on-chip cell culture and electrochemical cell lysis) we have designed, fabricated, and characterized an integrated microfluidic platform capable of culturing HeLa, MCF-7, Jurkat, and CHO-K1 cells for up to five days and subsequently lysing the cells without the need to add lysing reagents. On-demand lysis was accomplished by local hydroxide ion generation within microfluidic chambers, releasing both proteinacious (GFP) and genetic (Hoescht-stained DNA) material. Sample proteins exposed to the electrochemical lysis conditions were immunodetectable (p53) and their enzymatic activity (HRP) was investigated.
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Affiliation(s)
- J Tanner Nevill
- Biomolecular Nanotechnology Center, Berkeley Sensor & Actuator Center, Department of Bioengineering, University of California, UCSF/UCB Joint Graduate Group in Bioengineering, Berkeley, CA, USA
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27
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Liu Y, Xue Y, Ji J, Chen X, Kong J, Yang P, Girault HH, Liu B. Gold Nanoparticle Assembly Microfluidic Reactor for Efficient On-line Proteolysis. Mol Cell Proteomics 2007; 6:1428-36. [PMID: 17519226 DOI: 10.1074/mcp.t600055-mcp200] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
A microchip reactor coated with a gold nanoparticle network entrapping trypsin was designed for the efficient on-line proteolysis of low level proteins and complex extracts originating from mouse macrophages. The nanostructured surface coating was assembled via a layer-by-layer electrostatic binding of poly(diallyldimethylammonium chloride) and gold nanoparticles. The assembly process was monitored by UV-visible spectroscopy, atomic force microscopy, and quartz crystal microbalance. The controlled adsorption of trypsin was theoretically studied on the basis of the Langmuir isotherm model, and the fitted Gamma(max) and K values were estimated to be 1.2 x 10(-7) mol/m(2) and 4.1 x 10(5) M(-1), respectively. An enzymatic kinetics assay confirmed that trypsin, which was entrapped in the biocompatible gold nanoparticle network with a high loading capacity, preserved its bioactivity. The maximum proteolytic rate of the adsorbed trypsin was 400 mM/(min.microg). Trace amounts of proteins down to femtomole per analysis were digested using the microchip reactor, and the resulting tryptic products were identified by MALDI-TOF MS/MS. The protein mixtures extracted from the mouse macrophages were efficiently identified by on-line digestion and LC-ESI-MS/MS analysis.
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Affiliation(s)
- Yun Liu
- Department of Chemistry and Institute of Biomedical Sciences, Fudan University, Shanghai 200433, China
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28
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Ebara M, Hoffman JM, Stayton PS, Hoffman AS. Surface modification of microfluidic channels by UV-mediated graft polymerization of non-fouling and ‘smart’ polymers. Radiat Phys Chem Oxf Engl 1993 2007. [DOI: 10.1016/j.radphyschem.2007.02.072] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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29
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Hawkins KR, Steedman MR, Baldwin RR, Fu E, Ghosal S, Yager P. A method for characterizing adsorption of flowing solutes to microfluidic device surfaces. LAB ON A CHIP 2007; 7:281-5. [PMID: 17268632 DOI: 10.1039/b612894g] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
We present a method for characterizing the adsorption of solutes in microfluidic devices that is sensitive to both long-lived and transient adsorption and can be applied to a variety of realistic device materials, designs, fabrication methods, and operational parameters. We have characterized the adsorption of two highly adsorbing molecules (FITC-labeled bovine serum albumin (BSA) and rhodamine B) and compared these results to two low adsorbing species of similar molecular weights (FITC-labeled dextran and fluorescein). We have also validated our method by demonstrating that two well-known non-fouling strategies [deposition of the polyethylene oxide (PEO)-like surface coating created by radio-frequency glow discharge plasma deposition (RF-GDPD) of tetraethylene glycol dimethyl ether (tetraglyme, CH(3)O(CH(2)CH(2)O)(4)CH(3)), and blocking with unlabeled BSA] eliminate the characteristic BSA adsorption behavior observed otherwise.
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Affiliation(s)
- Kenneth R Hawkins
- Department of Bioengineering, University of Washington, Seattle, WA, USA.
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30
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Salim M, O'Sullivan B, McArthur SL, Wright PC. Characterization of fibrinogen adsorption onto glass microcapillary surfaces by ELISA. LAB ON A CHIP 2007; 7:64-70. [PMID: 17180206 DOI: 10.1039/b612521m] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Adsorption of biomolecules onto microchannel surfaces remains a critical issue in microfluidic devices. This paper investigates the adsorption of fibrinogen on glass microcapillaries using an immunoassay method (ELISA) and X-ray photoelectron spectroscopy (XPS). Various adsorption conditions such as protein concentrations and incubation times, buffer pH, buffer ionic strengths and effects of flow are presented. ELISA is successfully demonstrated as a facile and robust technique to examine these phenomena. The highest adsorption level occurs near the isoelectric point of fibrinogen (pH 5.0) and low buffer ionic strengths (0-8 mM). Microchannel surface saturation was achieved at a fibrinogen solution concentration of approximately 50 microg ml(-1). Fibrinogen adsorption under flow was always higher than that seen in static systems. The importance of diffusion phenomena in microchannels on protein adsorption was demonstrated. ELISA experiments using fused silica and PEEK have also confirmed significant adsorption on these mass spectrometer transfer line materials.
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Affiliation(s)
- Malinda Salim
- Department of Chemical and Process Engineering, University of Sheffield, Mappin Street, Sheffield, S1 3JD, UK
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31
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Liu Y, Zhong W, Meng S, Kong J, Lu H, Yang P, Girault HH, Liu B. Assembly-Controlled Biocompatible Interface on a Microchip: Strategy to Highly Efficient Proteolysis. Chemistry 2006; 12:6585-91. [PMID: 16800018 DOI: 10.1002/chem.200501622] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
A biocompatible interface was constructed on a microchip by using the layer-by-layer (LBL) assembly of charged polysaccharides incorporating proteases for highly efficient proteolysis. The controlled assembly of natural polyelectrolytes and the enzyme-adsorption step were monitored by using a quartz-crystal microbalance and atomic force microscopy (AFM). Such a multilayer-assembled membrane provides a biocompatible interconnected network with high enzyme-loading capacity. The maximum digestion rate of the adsorbed trypsin in a microchannel was significantly accelerated to 1600 mM min(-1) microg(-1), compared with the tryptic digestion in solution. Based on the Langmuir isotherm model, the thermodynamic constant of adsorption K was calculated to be 1.6 x 10(5) M(-1) and the maximum adsorption loading Gammamax was 3.6 x 10(-6) mol m(-2), 30 times more than a monolayer of trypsin on the native surface. The tunable interface containing trypsin was employed to construct a microchip reactor for digestion of femtomoles of proteins and the produced peptides were analyzed by MALDI-TOF mass spectroscopy. The efficient on-chip proteolysis was obtained within a few seconds, and the identification of biological samples was feasible.
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Affiliation(s)
- Yun Liu
- Department of Chemistry, Institute of Biomedical Sciences, Fudan University, Shanghai 200433, P. R. China
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32
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Lionello A, Josserand J, Jensen H, Girault HH. Dynamic protein adsorption in microchannels by "stop-flow" and continuous flow. LAB ON A CHIP 2005; 5:1096-103. [PMID: 16175266 DOI: 10.1039/b506009e] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
This work addresses two ways of loading proteins on microchannel surfaces for immunoassay applications: the "stop-flow" and the continuous flow processes. The "stop-flow" method consists of successive static incubation periods where the bulk solution depletes upon the adsorption process. In the present paper, a multi-step "stop-flow" protein coating is studied and compared to a coating under continuous flow conditions. For the "stop-flow", a non-dimensional parameter is here introduced, indicating the adsorbing capacity of the system, by which it is possible to calculate the number of loads necessary to reach the optimum coverage. For the continuous flow, the effects on the adsorption of the kinetic rates, flow velocity and wall capacity have been considered. This study shows the importance of a careful choice of the fluid velocity to minimise the sample waste. For diffusion controlled and kinetics controlled processes, two flow velocity criteria are provided in order to obtain the best possible coverage, with the same amount of sample as with the "stop-flow".
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Affiliation(s)
- Andrea Lionello
- Laboratoire d'Electrochimie Physique et Analytique, Institut des Sciences et Ingénierie Chimiques (ISIC), Ecole Polytechnique Fédérale de Lausanne, CH-1015, Lausanne, Switzerland
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