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Comparison of blocking reagents for antibody microarray-based immunoassays on glass and paper membrane substrates. Anal Bioanal Chem 2023; 415:1967-1977. [PMID: 36829042 DOI: 10.1007/s00216-023-04614-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Revised: 02/14/2023] [Accepted: 02/17/2023] [Indexed: 02/26/2023]
Abstract
Background noise due to nonspecific binding of biomolecules on the assay substrates is one of the most common challenges that limits the sensitivity of microarray-based immunoassays. Background signal intensity usually increases when complex biological fluids are used because they have a combination of molecules and vesicles that can adsorb onto substrate surfaces. Blocking strategies coupled with surface chemistries can reduce such nonspecific binding and improve assay sensitivity. In this paper, we conducted a systematic optimization of blocking strategies on a variety of commonly used substrates for protein measurement in complex biofluids. Four blocking strategies (BSA, non-fat milk, PEG, and a protein-free solution) coupled with four surface chemistries (3-glycidoxypropyltrimethoxysilane (GPS), poly-L-lysine (PLL), aminoalkylsilane (AAS), and nitrocellulose (NC)) were studied for their effect on background, microspot, and net signal intensities. We have also explored the effect that these blocking strategies have when proteins in complex samples (plasma, serum, cell culture media, and EV lysate) are measured. Irregular spot morphology could affect signal extraction using automated software. We found that the microspots with the best morphology were the ones printed on GPS glass surfaces for all immunoassays. On NC membrane, the protein-based blocking strategies yielded the highest net fluorescent intensity with the antigen contained in PBS, plasma, serum, and serum-free cell culture media. Differently, with EV lysate samples, Pierce™ protein-free blocker yielded the best net signal intensity on both GPS and NC surfaces. The choice of blocking strategies highly depends on the substrate. Moreover, the findings discovered in this study are not limited to microarray-based immunoassays but can provide insights for other assay formats.
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2
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Fischer T, Tenbusch J, Möller M, Singh S. A facile method for grafting functional hydrogel films on PTFE, PVDF, and TPX polymers. SOFT MATTER 2022; 18:4315-4324. [PMID: 35621021 DOI: 10.1039/d2sm00313a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
The use of polymeric materials in biomedical applications requires a judicious control of surface properties as they are directly related to cellular interactions and biocompatibility. The most desired chemical surface properties include hydrophilicity and the presence of functional groups for surface modification. In this work, we describe a method to graft a highly stable, ultra-thin, amine-functional hydrogel layer onto highly inert surfaces of poly(tetrafluoroethylene) (PTFE), poly(vinylidene fluoride) (PVDF), and poly(4-methyl-1-pentene) (PMP or TPX). Covalent grafting is realized with hydrophilic poly(vinylamine-co-acetamide)s by C-H insertion crosslinking (CHic) chemistry initiated by UV light. These polyvinylamides carry tetrafluorophenyl azide groups as photo or thermo activated binding sites and contain further free amine groups, which can be used to bind peptides such as biological ligands, polysaccharides, or other hydrogel layers. The covalently bound surface layers resist intensive Soxhlet extraction confirming the stability of the coating. Fluorescent staining verified the accessibility of free primary amine groups, which can be used for the functionalization of the surface with bioactive molecules. The coating demonstrates hydrophobic wetting behavior when conditioned in air and hydrophilic wetting behavior when conditioned in water showing the presence of loosely crosslinked polymer chains that can re-orient. We believe that the reported application of CHic for the surface modification of fluorinated polymers like PTFE and PVDF as well as TPX can form the basis for advanced biocompatible and biofunctional surface engineering.
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Affiliation(s)
- Thorsten Fischer
- DWI-Leibniz-Institute for Interactive Materials e.V., Forckenbeckstr. 50, 52056 Aachen, Germany
| | - Jan Tenbusch
- DWI-Leibniz-Institute for Interactive Materials e.V., Forckenbeckstr. 50, 52056 Aachen, Germany
| | - Martin Möller
- DWI-Leibniz-Institute for Interactive Materials e.V., Forckenbeckstr. 50, 52056 Aachen, Germany
| | - Smriti Singh
- DWI-Leibniz-Institute for Interactive Materials e.V., Forckenbeckstr. 50, 52056 Aachen, Germany
- Max-Planck-Institut für medizinische Forschung, Jahnstraße 29, 69120 Heidelberg, Germany.
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3
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Bergamaschi G, Musicò A, Frigerio R, Strada A, Pizzi A, Talone B, Ghezzi J, Gautieri A, Chiari M, Metrangolo P, Vanna R, Baldelli Bombelli F, Cretich M, Gori A. Composite Peptide-Agarose Hydrogels for Robust and High-Sensitivity 3D Immunoassays. ACS APPLIED MATERIALS & INTERFACES 2022; 14:4811-4822. [PMID: 35060693 DOI: 10.1021/acsami.1c18466] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Canonical immunoassays rely on highly sensitive and specific capturing of circulating biomarkers by interacting biomolecular baits. In this frame, bioprobe immobilization in spatially discrete three-dimensional (3D) spots onto analytical surfaces by hydrogel encapsulation was shown to provide relevant advantages over conventional two-dimensional (2D) platforms. Yet, the broad application of 3D systems is still hampered by hurdles in matching their straightforward fabrication with optimal functional properties. Herein, we report on a composite hydrogel obtained by combining a self-assembling peptide (namely, Q3 peptide) with low-temperature gelling agarose that is proved to have simple and robust application in the fabrication of microdroplet arrays, overcoming hurdles and limitations commonly associated with 3D hydrogel assays. We demonstrate the real-case scenario feasibility of our 3D system in the profiling of Covid-19 patients' serum IgG immunoreactivity, which showed remarkably improved signal-to-noise ratio over canonical assays in the 2D format and exquisite specificity. Overall, the new two-component hydrogel widens the perspectives of hydrogel-based arrays and represents a step forward towards their routine use in analytical practices.
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Affiliation(s)
- Greta Bergamaschi
- Istituto di Scienze e Tecnologie Chimiche "Giulio Natta"─National Research Council of Italy (SCITEC-CNR), 20131 Milan, Italy
| | - Angelo Musicò
- Istituto di Scienze e Tecnologie Chimiche "Giulio Natta"─National Research Council of Italy (SCITEC-CNR), 20131 Milan, Italy
| | - Roberto Frigerio
- Istituto di Scienze e Tecnologie Chimiche "Giulio Natta"─National Research Council of Italy (SCITEC-CNR), 20131 Milan, Italy
| | - Alessandro Strada
- Istituto di Scienze e Tecnologie Chimiche "Giulio Natta"─National Research Council of Italy (SCITEC-CNR), 20131 Milan, Italy
- Laboratory of Supramolecular and Bio-Nanomaterials (SBNLab), Department of Chemistry, Materials and Chemical Engineering "Giulio Natta", Politecnico di Milano, Via Luigi Mancinelli 7, 20131 Milan, Italy
| | - Andrea Pizzi
- Laboratory of Supramolecular and Bio-Nanomaterials (SBNLab), Department of Chemistry, Materials and Chemical Engineering "Giulio Natta", Politecnico di Milano, Via Luigi Mancinelli 7, 20131 Milan, Italy
| | - Benedetta Talone
- Physics Department, Politecnico di Milano, P.zza Leonardo da Vinci 32, 20133 Milan, Italy
| | - Jacopo Ghezzi
- Istituto di Scienze e Tecnologie Chimiche "Giulio Natta"─National Research Council of Italy (SCITEC-CNR), 20131 Milan, Italy
- Biomolecular Engineering Lab, Dept. Electronics, Information and Bioengineering, Politecnico di Milano, 20133 Milan, Italy
| | - Alfonso Gautieri
- Biomolecular Engineering Lab, Dept. Electronics, Information and Bioengineering, Politecnico di Milano, 20133 Milan, Italy
| | - Marcella Chiari
- Istituto di Scienze e Tecnologie Chimiche "Giulio Natta"─National Research Council of Italy (SCITEC-CNR), 20131 Milan, Italy
| | - Pierangelo Metrangolo
- Laboratory of Supramolecular and Bio-Nanomaterials (SBNLab), Department of Chemistry, Materials and Chemical Engineering "Giulio Natta", Politecnico di Milano, Via Luigi Mancinelli 7, 20131 Milan, Italy
| | - Renzo Vanna
- Istituto di Fotonica e Nanotecnologie─National Research Council of Italy (IFN-CNR), 20133 Milan, Italy
| | - Francesca Baldelli Bombelli
- Laboratory of Supramolecular and Bio-Nanomaterials (SBNLab), Department of Chemistry, Materials and Chemical Engineering "Giulio Natta", Politecnico di Milano, Via Luigi Mancinelli 7, 20131 Milan, Italy
| | - Marina Cretich
- Istituto di Scienze e Tecnologie Chimiche "Giulio Natta"─National Research Council of Italy (SCITEC-CNR), 20131 Milan, Italy
| | - Alessandro Gori
- Istituto di Scienze e Tecnologie Chimiche "Giulio Natta"─National Research Council of Italy (SCITEC-CNR), 20131 Milan, Italy
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4
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Len’shina NA, Shurygina MP, Chesnokov SA. Photoreduction Reaction of Carbonyl-Containing Compounds in the Synthesis and Modification of Polymers. POLYMER SCIENCE SERIES B 2021. [DOI: 10.1134/s1560090421060130] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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5
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Straub AJ, Scherag FD, Kim HI, Steiner MS, Brandstetter T, Rühe J. "CHicable" and "Clickable" Copolymers for Network Formation and Surface Modification. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2021; 37:6510-6520. [PMID: 34003660 DOI: 10.1021/acs.langmuir.1c00669] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
In this study, we present the generation of novel, multifunctional polymer networks through a combination of C,H-insertion cross-linking (CHic) and click chemistry. To this, copolymers consisting of hydrophilic N,N-dimethylacrylamide as matrix component and repeat units containing azide moieties, as well as benzophenone or anthraquinone groups, are generated. The benzophenone or anthraquinone groups allow photo-cross-linking, surface attachment or covalent immobilization of adjacent (bio)molecules through CHic reactions. The azide moieties either can react with available alkynes through conventional click reactions or can be activated to form nitrenes, which can also undergo CHic reactions. By choosing appropriate reaction conditions, the same polymer can be used to follow very different reaction paths, opening up a plethora of choices for the generation of functional polymer networks. In the exemplary presented case ("CHic-Click"), irradiation of the copolymers with UV-A light (λirr = 365 nm) leads to cross-linking (network formation) and surface attachment simultaneously. The azide units remain intact during this cross-linking step, and alkyne-modified (bio)molecules can be bound through click reactions. Biofunctionalization of the polymer network with alkynylated streptavidin, followed by application of biotin-conjugated antibody and a model analyte, highlights the potential of these surface architectures as a toolbox which can be adapted for diverse bioanalytical applications.
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Affiliation(s)
- Alexander J Straub
- Laboratory for Chemistry and Physics of Interfaces, Department of Microsystems Engineering (IMTEK), University of Freiburg, Georges-Köhler-Allee 103, 79110 Freiburg, Germany
| | - Frank D Scherag
- Laboratory for Chemistry and Physics of Interfaces, Department of Microsystems Engineering (IMTEK), University of Freiburg, Georges-Köhler-Allee 103, 79110 Freiburg, Germany
| | - Hye In Kim
- Laboratory for Chemistry and Physics of Interfaces, Department of Microsystems Engineering (IMTEK), University of Freiburg, Georges-Köhler-Allee 103, 79110 Freiburg, Germany
| | - Mark-Steven Steiner
- Microcoat Biotechnologie GmbH, Am Neuland 3, 82347 Bernried am Starnberger See, Germany
| | - Thomas Brandstetter
- Laboratory for Chemistry and Physics of Interfaces, Department of Microsystems Engineering (IMTEK), University of Freiburg, Georges-Köhler-Allee 103, 79110 Freiburg, Germany
| | - Jürgen Rühe
- Laboratory for Chemistry and Physics of Interfaces, Department of Microsystems Engineering (IMTEK), University of Freiburg, Georges-Köhler-Allee 103, 79110 Freiburg, Germany
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6
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Ching-Bin Ke, Jian-Lian Chen. Polyimide Substrates Pre-Treated by Capacitively Coupled Plasma and Coated with Composites of Tetracycline-Imprinted Polymethacrylates and Quantum Dots as Fluorescent Sensors. JOURNAL OF ANALYTICAL CHEMISTRY 2020. [DOI: 10.1134/s1061934820090063] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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7
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Stöbener DD, Weinhart M. Thermoresponsive Poly(glycidyl ether) Brush Coatings on Various Tissue Culture Substrates-How Block Copolymer Design and Substrate Material Govern Self-Assembly and Phase Transition. Polymers (Basel) 2020; 12:E1899. [PMID: 32846926 PMCID: PMC7563243 DOI: 10.3390/polym12091899] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 08/19/2020] [Accepted: 08/22/2020] [Indexed: 01/06/2023] Open
Abstract
Thermoresponsive poly(glycidyl ether) brushes can be grafted to applied tissue culture substrates and used for the fabrication of primary human cell sheets. The self-assembly of such brushes is achieved via the directed physical adsorption and subsequent UV immobilization of block copolymers equipped with a short, photo-reactive benzophenone-based anchor block. Depending on the chemistry and hydrophobicity of the benzophenone anchor, we demonstrate that such block copolymers exhibit distinct thermoresponsive properties and aggregation behaviors in water. Independent on the block copolymer composition, we developed a versatile grafting-to process which allows the fabrication of poly(glycidyl ether) brushes on various tissue culture substrates from dilute aqueous-ethanolic solution. The viability of this process crucially depends on the chemistry and hydrophobicity of, both, benzophenone-based anchor block and substrate material. Utilizing these insights, we were able to manufacture thermoresponsive poly(glycidyl ether) brushes on moderately hydrophobic polystyrene and polycarbonate as well as on rather hydrophilic polyethylene terephthalate and tissue culture-treated polystyrene substrates. We further show that the temperature-dependent switchability of the brush coatings is not only dependent on the cloud point temperature of the block copolymers, but also markedly governed by the hydrophobicity of the surface-bound benzophenone anchor and the subjacent substrate material. Our findings demonstrate that the design of amphiphilic thermoresponsive block copolymers is crucial for their phase transition characteristics in solution and on surfaces.
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Affiliation(s)
- Daniel David Stöbener
- Institute of Physical Chemistry and Electrochemistry, Leibniz Universität Hannover, Callinstr. 3A, 30167 Hannover, Germany;
- Institute of Chemistry and Biochemistry, Freie Universität Berlin, Takustr. 3, 14195 Berlin, Germany
| | - Marie Weinhart
- Institute of Physical Chemistry and Electrochemistry, Leibniz Universität Hannover, Callinstr. 3A, 30167 Hannover, Germany;
- Institute of Chemistry and Biochemistry, Freie Universität Berlin, Takustr. 3, 14195 Berlin, Germany
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8
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Seidi F, Zhao WF, Xiao HN, Jin YC, Saeb MR, Zhao CS. Advanced Surfaces by Anchoring Thin Hydrogel Layers of Functional Polymers. CHINESE JOURNAL OF POLYMER SCIENCE 2020. [DOI: 10.1007/s10118-020-2474-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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9
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Cimafonte M, Fulgione A, Gaglione R, Papaianni M, Capparelli R, Arciello A, Bolletti Censi S, Borriello G, Velotta R, Della Ventura B. Screen Printed Based Impedimetric Immunosensor for Rapid Detection of Escherichia coli in Drinking Water. SENSORS 2020; 20:s20010274. [PMID: 31947810 PMCID: PMC6982893 DOI: 10.3390/s20010274] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/29/2019] [Revised: 12/27/2019] [Accepted: 12/30/2019] [Indexed: 12/19/2022]
Abstract
The development of a simple and low cost electrochemical impedance immunosensor based on screen printed gold electrode for rapid detection of Escherichia coli in water is reported. The immunosensor is fabricated by immobilizing anti-E. coli antibodies onto a gold surface in a covalent way by the photochemical immobilization technique, a simple procedure able to bind antibodies upright onto gold surfaces. Impedance spectra are recorded in 0.01 M phosphate buffer solution (PBS) containing 10 mM Fe(CN)63−/Fe(CN)64− as redox probe. The Nyquist plots can be modelled with a modified Randles circuit, identifying the charge transfer resistance Rct as the relevant parameter after the immobilization of antibodies, the blocking with BSA and the binding of E. coli. The introduction of a standard amplification procedure leads to a significant enhancement of the impedance increase, which allows one to measure E. coli in drinking water with a limit of detection of 3 × 101 CFU mL−1 while preserving the rapidity of the method that requires only 1 h to provide a “yes/no” response. Additionally, by applying the Langmuir adsorption model, we are able to describe the change of Rct in terms of the “effective” electrode, which is modified by the detection of the analyte whose microscopic conducting properties can be quantified.
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Affiliation(s)
- Martina Cimafonte
- Department of Physics “Ettore Pancini”, University of Naples “Federico II”, Via Cinthia, 26, 80126 Naples, Italy; (M.C.); (R.V.)
| | - Andrea Fulgione
- Istituto Zooprofilattico Sperimentale del Mezzogiorno, Via Salute, 2, 80055 Portici Naples, Italy; (A.F.); (G.B.)
- Department of Agriculture, University of Naples “Federico II”, Via Università, 133, 80055 Portici Naples, Italy; (M.P.); (R.C.)
| | - Rosa Gaglione
- Department of Chemical Sciences, University of Naples “Federico II”, Via Cinthia, 26, 80126 Naples, Italy; (R.G.); (A.A.)
| | - Marina Papaianni
- Department of Agriculture, University of Naples “Federico II”, Via Università, 133, 80055 Portici Naples, Italy; (M.P.); (R.C.)
| | - Rosanna Capparelli
- Department of Agriculture, University of Naples “Federico II”, Via Università, 133, 80055 Portici Naples, Italy; (M.P.); (R.C.)
| | - Angela Arciello
- Department of Chemical Sciences, University of Naples “Federico II”, Via Cinthia, 26, 80126 Naples, Italy; (R.G.); (A.A.)
| | | | - Giorgia Borriello
- Istituto Zooprofilattico Sperimentale del Mezzogiorno, Via Salute, 2, 80055 Portici Naples, Italy; (A.F.); (G.B.)
| | - Raffaele Velotta
- Department of Physics “Ettore Pancini”, University of Naples “Federico II”, Via Cinthia, 26, 80126 Naples, Italy; (M.C.); (R.V.)
| | - Bartolomeo Della Ventura
- Department of Physics, Politecnico di Milano, Piazza Leonardo da Vinci, 32, 20133 Milano, Italy
- Correspondence:
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10
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Stumpf A, Brandstetter T, Hübner J, Rühe J. Hydrogel based protein biochip for parallel detection of biomarkers for diagnosis of a Systemic Inflammatory Response Syndrome (SIRS) in human serum. PLoS One 2019; 14:e0225525. [PMID: 31790441 PMCID: PMC6886838 DOI: 10.1371/journal.pone.0225525] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2019] [Accepted: 11/06/2019] [Indexed: 11/18/2022] Open
Abstract
The Systemic Inflammatory Response Syndrome (SIRS), a sepsis related inflammatory state, is a self-defense mechanism against specific and nonspecific stimuli. The six most extensively studied inflammatory biomarkers for the clinical diagnosis of SIRS are interleukin 4 (hIL-4), interleukin 6 (hIL-6), interleukin 10 (hIL-10), tumor necrosis factor alpha (hTNF-α), interferon gamma (hIFN-γ) and procalcitonin (hPCT). These biomarkers are naturally present (but usually only at low concentration) in SIRS infected patients [1, 2] and thus the development of a highly sensitive detection method is of major clinical interest. However, the existing analytical techniques are lacking in required analytical sensitivity and parallel determination of these biomarkers. We developed a fast, easy and cost-efficient protein microarray biochip where the capture molecules are attached on hydrogel spots, enabling SIRS diagnosis by parallel detection of these six clinically relevant biomarkers with a sample volume of 25 μl. With our hydrogel based protein microarray biochip we achieved a limit of detection for hIL-4 of 75.2 pg/ml, for hIL-6 of 45.1 pg/ml, for hIL-10 of 71.5 pg/ml, for hTNF-α of 56.7 pg/ml, for IFN-γ of 46.4 pg/ml and for hPCT of 1.1 ng/ml in spiked human serum demonstrating sufficient sensitivity for clinical usage. Additionally, we demonstrated successful detection of two relevant SIRS biomarkers in clinical patient samples with a turnaround time of the complete analysis from sample-to-answer in less than 200 minutes.
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Affiliation(s)
- Anne Stumpf
- Laboratory for Chemistry and Physics of Interfaces, Department of Microsystems Engineering, University of Freiburg, Georges-Koehler-Allee, Freiburg, Germany
| | - Thomas Brandstetter
- Laboratory for Chemistry and Physics of Interfaces, Department of Microsystems Engineering, University of Freiburg, Georges-Koehler-Allee, Freiburg, Germany
| | - Johannes Hübner
- Division of Pediatric Infectious Diseases, Dr. von Hauner Children's Hospital, Ludwig Maximilian's University, Munich, Germany, Lindwurmstr, Munich, Germany
| | - Jürgen Rühe
- Laboratory for Chemistry and Physics of Interfaces, Department of Microsystems Engineering, University of Freiburg, Georges-Koehler-Allee, Freiburg, Germany
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11
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Brittain WJ, Brandsetter T, Prucker O, Rühe J. The Surface Science of Microarray Generation-A Critical Inventory. ACS APPLIED MATERIALS & INTERFACES 2019; 11:39397-39409. [PMID: 31322854 DOI: 10.1021/acsami.9b06838] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Microarrays are powerful tools in biomedical research and have become indispensable for high-throughput multiplex analysis, especially for DNA and protein analysis. The basis for all microarray processing and fabrication is surface modification of a chip substrate and many different strategies to couple probe molecules to such substrates have been developed. We present here a critical assessment of typical biochip generation processes from a surface science point of view. While great progress has been made from a molecular biology point of view on the development of qualitative assays and impressive results have been obtained on the detection of rather low concentrations of DNA or proteins, quantitative chip-based assays are still comparably rare. We argue that lack of stable and reliable deposition chemistries has led in many cases to suboptimal quantitative reproducibility, impeded further progress in microarray development and prevented a more significant penetration of microarray technology into the diagnostic market. We suggest that surface-attached hydrogel networks might be a promising strategy to achieve highly sensitive and quantitatively reproducible microarrays.
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Affiliation(s)
- William J Brittain
- Department of Chemistry & Biochemistry , Texas State University , 601 University Drive , San Marcos , Texas 78666 , United States
- Department of Microsystems Engineering , University of Freiburg , Georges-Köhler-Allee 103 , Freiburg 79110 , Germany
| | - Thomas Brandsetter
- Department of Microsystems Engineering , University of Freiburg , Georges-Köhler-Allee 103 , Freiburg 79110 , Germany
| | - Oswald Prucker
- Department of Microsystems Engineering , University of Freiburg , Georges-Köhler-Allee 103 , Freiburg 79110 , Germany
| | - Jürgen Rühe
- Department of Microsystems Engineering , University of Freiburg , Georges-Köhler-Allee 103 , Freiburg 79110 , Germany
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12
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Díaz-Betancor Z, Bañuls MJ, Maquieira Á. Photoclick chemistry to create dextran-based nucleic acid microarrays. Anal Bioanal Chem 2019; 411:6745-6754. [PMID: 31482291 DOI: 10.1007/s00216-019-02050-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2019] [Revised: 07/22/2019] [Accepted: 07/24/2019] [Indexed: 11/29/2022]
Abstract
In the literature, there are reports of the utilization of various hydrogels to create generic platforms for protein microarray applications. Here, a novel strategy was developed to obtain high-performance microarrays. In it, a dextran hydrogel is used to covalently immobilize oligonucleotides and proteins. This method employs aqueous solutions of dextran methacrylate (Dx-MA), which is a biocompatible photopolymerizable monomer. Capture probes are immobilized inside the hydrogel via a light-induced thiol-acrylate coupling reaction at the same time as the dextran polymer is formed. Hydrogel microarrays based on this technique were prepared on different surfaces, such as a Blu-ray Disk and polycarbonate or alkene-functionalized glass slides, and these systems showed high probe-loading capabilities and good biorecognition yields. This methodology presents advantages such as a low cost, a short analysis time, a low limit of detection, and multiplexing capabilities, among others. Confocal fluorescence microscopy analysis demonstrated that in these hydrogel-based microarrays, receptor immobilization and the biorecognition event occurred within the hydrogel and not merely on the surface.
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Affiliation(s)
- Zeneida Díaz-Betancor
- IDM, Instituto Interuniversitario de Investigación de Reconocimiento Molecular y Desarrollo Tecnológico, Universitat Politècnica de València, Universitat de València, Camino de Vera s/n, 46022, Valencia, Spain
| | - María-José Bañuls
- IDM, Instituto Interuniversitario de Investigación de Reconocimiento Molecular y Desarrollo Tecnológico, Universitat Politècnica de València, Universitat de València, Camino de Vera s/n, 46022, Valencia, Spain. .,Departamento de Química, Universitat Politècnica de València, Camino de Vera s/n, 46022, Valencia, Spain.
| | - Ángel Maquieira
- IDM, Instituto Interuniversitario de Investigación de Reconocimiento Molecular y Desarrollo Tecnológico, Universitat Politècnica de València, Universitat de València, Camino de Vera s/n, 46022, Valencia, Spain.,Departamento de Química, Universitat Politècnica de València, Camino de Vera s/n, 46022, Valencia, Spain
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13
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Phosphorylcholine-based hydrogel for immobilization of biomolecules. Application to fluorometric microarrays for use in hybridization assays and immunoassays, and nanophotonic biosensing. Mikrochim Acta 2019; 186:570. [DOI: 10.1007/s00604-019-3691-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Accepted: 07/07/2019] [Indexed: 12/11/2022]
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14
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Gagni P, Romanato A, Bergamaschi G, Bettotti P, Vanna R, Piotto C, Morasso CF, Chiari M, Cretich M, Gori A. A self-assembling peptide hydrogel for ultrarapid 3D bioassays. NANOSCALE ADVANCES 2019; 1:490-497. [PMID: 36132256 PMCID: PMC9473263 DOI: 10.1039/c8na00158h] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2018] [Accepted: 10/22/2018] [Indexed: 05/08/2023]
Abstract
Biosensing analytical platforms rely on the intimate structure-function relationship of immobilized probes. In this context, hydrogels are appealing semi-wet systems to locally confine biomolecules while preserving their structural integrity and function. Yet, limitations imposed by biomolecule diffusion rates or fabrication difficulties still hamper their broad application. Here, using a self-assembling peptide, a printable and self-adhesive hydrogel was obtained and applied to fabricate arrays of localized bio-functional 3D microenvironments on analytical interfaces. This soft matrix represents a robust and versatile material, allowing fast and selective tuning of analyte diffusion, which is exploited here to run in-gel immunoassays under solution-like conditions in an unprecedented (<10 min) time frame. The developed material overcomes major limitations associated with hydrogels for bioassays, widening the prospects for easy fabrication of multifunctional bio-interfaces for high-throughput, molecular recognition assays.
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Affiliation(s)
- Paola Gagni
- National Research Council of Italy, Istituto di Chimica del Riconoscimento Molecolare (ICRM) Via Mario Bianco, 9 20131-Milano Italy
| | - Alessandro Romanato
- National Research Council of Italy, Istituto di Chimica del Riconoscimento Molecolare (ICRM) Via Mario Bianco, 9 20131-Milano Italy
| | - Greta Bergamaschi
- National Research Council of Italy, Istituto di Chimica del Riconoscimento Molecolare (ICRM) Via Mario Bianco, 9 20131-Milano Italy
| | - Paolo Bettotti
- Nanoscience Laboratory, Department of Physics, University of Trento Via Sommarive 14 38123 Povo Italy
| | - Renzo Vanna
- Istituti Clinici Scientifici Maugeri IRCCS Via Maugeri 4 27100 Pavia Italy
| | - Chiara Piotto
- Nanoscience Laboratory, Department of Physics, University of Trento Via Sommarive 14 38123 Povo Italy
| | - Carlo F Morasso
- Istituti Clinici Scientifici Maugeri IRCCS Via Maugeri 4 27100 Pavia Italy
| | - Marcella Chiari
- National Research Council of Italy, Istituto di Chimica del Riconoscimento Molecolare (ICRM) Via Mario Bianco, 9 20131-Milano Italy
| | - Marina Cretich
- National Research Council of Italy, Istituto di Chimica del Riconoscimento Molecolare (ICRM) Via Mario Bianco, 9 20131-Milano Italy
| | - Alessandro Gori
- National Research Council of Italy, Istituto di Chimica del Riconoscimento Molecolare (ICRM) Via Mario Bianco, 9 20131-Milano Italy
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15
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Widyaya VT, Müller C, Al-Ahmad A, Lienkamp K. Three-Dimensional, Bifunctional Microstructured Polymer Hydrogels Made from Polyzwitterions and Antimicrobial Polymers. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:1211-1226. [PMID: 30563333 PMCID: PMC7611509 DOI: 10.1021/acs.langmuir.8b03410] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Biofilm-associated infections of medical devices are a global problem. For the prevention of such infections, biomaterial surfaces are chemically or topographically modified to slow down the initial stages of biofilm formation. In the bifunctional material here presented, chemical and topographical cues are combined, so that protein and bacterial adhesion as well as bacterial proliferation are effectively inhibited. Upon changes in the surface topography parameters and investigation of the effect of these changes on bioactivity, structure-property relationships are obtained. The target material is obtained by microcontact printing (μCP), a soft lithography method. The antimicrobial component, poly(oxanorbornene)-based synthetic mimics of an antimicrobial peptide (SMAMP), was printed onto a protein-repellent polysulfobetaine hydrogel, so that bifunctional 3D structured polymer surfaces with 1, 2, and 8.5 μm spacing are obtained. These surfaces are characterized with fluorescence microscopy, surface plasmon resonance spectroscopy, atomic force microscopy, and contact angle measurements. Biological studies show that the bifunctional surfaces with 1 and 2 μm spacing are 100% antimicrobially active against Escherichia coli and Staphylococcus aureus, 100% fibrinogen-repellent, and nontoxic to human gingival mucosal keratinocytes. At 8.5 μm spacing, the broad-band antimicrobial activity and the protein repellency are compromised, which indicates that this spacing is above the upper limit for effective simultaneous antimicrobial activity and protein repellency of polyzwitterionic-polycationic materials.
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Affiliation(s)
- Vania Tanda Widyaya
- Bioactive Polymer Synthesis and Surface Engineering Group, Department of Microsystems Engineering (IMTEK) and Freiburg Center for Interactive Materials and Bioinspired Technologies (FIT), Albert-Ludwigs-Universität Freiburg, Georges-Köhler-Allee 105, 79110 Freiburg, Germany
| | - Claas Müller
- Laboratory for Process Technology, Department of Microsystem Engineering (IMTEK), Albert-Ludwigs-Universität Freiburg, Georges-Köhler-Allee 103, 79110 Freiburg, Germany
| | - Ali Al-Ahmad
- Department of Operative Dentistry and Periodontology, Center for Dental Medicine of the Albert-Ludwigs-Universität, Freiburg, Hugstetter Str. 55, 79106 Germany
| | - Karen Lienkamp
- Bioactive Polymer Synthesis and Surface Engineering Group, Department of Microsystems Engineering (IMTEK) and Freiburg Center for Interactive Materials and Bioinspired Technologies (FIT), Albert-Ludwigs-Universität Freiburg, Georges-Köhler-Allee 105, 79110 Freiburg, Germany
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16
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Randriantsilefisoa R, Cuellar-Camacho JL, Chowdhury MS, Dey P, Schedler U, Haag R. Highly sensitive detection of antibodies in a soft bioactive three-dimensional bioorthogonal hydrogel. J Mater Chem B 2019. [DOI: 10.1039/c9tb00234k] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
This three-dimensional detection method of antibodies offers a high sensitivity and good biomolecule stability for new biosensing devices.
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Affiliation(s)
| | | | | | - Pradip Dey
- Institut für Chemie und Biochemie
- Freie Universität Berlin
- Takustr. 3
- Berlin
- Germany
| | - Uwe Schedler
- PolyAn GmbH
- Rudolf-Baschant-Strasse 2
- 13086 Berlin
- Germany
| | - Rainer Haag
- Institut für Chemie und Biochemie
- Freie Universität Berlin
- Takustr. 3
- Berlin
- Germany
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17
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Scherag FD, Mader A, Zinggeler M, Birsner N, Kneusel RE, Brandstetter T, Rühe J. Blocking-Free and Substrate-Independent Serological Microarray Immunoassays. Biomacromolecules 2018; 19:4641-4649. [DOI: 10.1021/acs.biomac.8b01334] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- Frank D. Scherag
- Laboratory for Chemistry and Physics of Interfaces, Department of Microsystems Engineering (IMTEK), University of Freiburg, Georges-Köhler-Allee 103, 79110 Freiburg, Germany
| | - Andreas Mader
- Scienion AG, Volmerstrasse 7b, 12489 Berlin, Germany
| | - Marc Zinggeler
- Laboratory for Chemistry and Physics of Interfaces, Department of Microsystems Engineering (IMTEK), University of Freiburg, Georges-Köhler-Allee 103, 79110 Freiburg, Germany
| | - Nicole Birsner
- Laboratory for Chemistry and Physics of Interfaces, Department of Microsystems Engineering (IMTEK), University of Freiburg, Georges-Köhler-Allee 103, 79110 Freiburg, Germany
| | | | - Thomas Brandstetter
- Laboratory for Chemistry and Physics of Interfaces, Department of Microsystems Engineering (IMTEK), University of Freiburg, Georges-Köhler-Allee 103, 79110 Freiburg, Germany
| | - Jürgen Rühe
- Laboratory for Chemistry and Physics of Interfaces, Department of Microsystems Engineering (IMTEK), University of Freiburg, Georges-Köhler-Allee 103, 79110 Freiburg, Germany
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18
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Surface-attached hydrogel coatings via C,H-insertion crosslinking for biomedical and bioanalytical applications (Review). Biointerphases 2018; 13:010801. [DOI: 10.1116/1.4999786] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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19
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Kotrade PF, Rühe J. Malonic Acid Diazoesters for C−H Insertion Crosslinking (CHic) Reactions: A Versatile Method for the Generation of Tailor-Made Surfaces. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201704486] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Affiliation(s)
- Philip F. Kotrade
- Department of Mircosystems Engineering (IMTEK); University Freiburg; Georges-Köhler-Allee 103 Freiburg Germany
| | - Jürgen Rühe
- Department of Mircosystems Engineering (IMTEK); University Freiburg; Georges-Köhler-Allee 103 Freiburg Germany
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20
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Kotrade PF, Rühe J. Malonic Acid Diazoesters for C−H Insertion Crosslinking (CHic) Reactions: A Versatile Method for the Generation of Tailor-Made Surfaces. Angew Chem Int Ed Engl 2017; 56:14405-14410. [DOI: 10.1002/anie.201704486] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2017] [Revised: 08/04/2017] [Indexed: 12/19/2022]
Affiliation(s)
- Philip F. Kotrade
- Department of Mircosystems Engineering (IMTEK); University Freiburg; Georges-Köhler-Allee 103 Freiburg Germany
| | - Jürgen Rühe
- Department of Mircosystems Engineering (IMTEK); University Freiburg; Georges-Köhler-Allee 103 Freiburg Germany
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21
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Chen JL. Determination of tetracycline using imprinted polymethacrylates along with fluorescent CdTe quantum dots on plastic substrates. Mikrochim Acta 2017. [DOI: 10.1007/s00604-017-2118-2] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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22
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Scherag FD, Niestroj-Pahl R, Krusekopf S, Lücke K, Brandstetter T, Rühe J. Highly Selective Capture Surfaces on Medical Wires for Fishing Tumor Cells in Whole Blood. Anal Chem 2017; 89:1846-1854. [PMID: 28208267 DOI: 10.1021/acs.analchem.6b04219] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The detection of circulating tumor cells (CTCs) in the blood of cancer patients is a challenging task. CTCs are, especially at the early stages of cancer development, extremely rare cells hidden in a vast background of regular blood cells. We describe a new strategy for the isolation of CTCs from whole blood. The key component is a medical wire coated with a multilayer assembly that allows highly specific capture of EpCAM (epithelial cell adhesion molecule) positive CTCs from blood. The assembly is generated in a layer-by-layer fashion through photochemically induced C,H insertion reactions and consists of a protective layer, which shields the contacting solution from the metal, a protein resistant layer, which prevents nonspecific interactions with proteins and a layer containing the EpCAM antibodies. In vitro experiments show that these surfaces can capture tumor cells from whole blood with enrichment factors (specifically vs nonspecifically bound cells) of up to about 3000 compared to the number of leucocytes in the blood. The purity of the isolated cells is greater than 90%. After "fishing" them from the blood, the cells, still bound to the wire, can be genetically analyzed. This demonstrates that this strategy might prove useful for next generation sequencing.
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Affiliation(s)
- Frank D Scherag
- Department of Microsystems Engineering, University of Freiburg , Georges-Köhler-Allee 103, D-79110 Freiburg, Germany
| | | | | | - Klaus Lücke
- GILUPI GmbH , Hermannswerder 20a, 14473 Potsdam, Germany
| | - Thomas Brandstetter
- Department of Microsystems Engineering, University of Freiburg , Georges-Köhler-Allee 103, D-79110 Freiburg, Germany
| | - Jürgen Rühe
- Department of Microsystems Engineering, University of Freiburg , Georges-Köhler-Allee 103, D-79110 Freiburg, Germany
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Gao W, Wang W, Yao S, Wu S, Zhang H, Zhang J, Jing F, Mao H, Jin Q, Cong H, Jia C, Zhang G, Zhao J. Highly sensitive detection of multiple tumor markers for lung cancer using gold nanoparticle probes and microarrays. Anal Chim Acta 2016; 958:77-84. [PMID: 28110687 DOI: 10.1016/j.aca.2016.12.016] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2016] [Revised: 10/18/2016] [Accepted: 12/07/2016] [Indexed: 01/10/2023]
Abstract
Assay of multiple serum tumor markers such as carcinoembryonic antigen (CEA), cytokeratin 19 fragment antigen (CYFRA21-1), and neuron specific enolase (NSE), is important for the early diagnosis of lung cancer. Dickkopf-1 (DKK1), a novel serological and histochemical biomarker, was recently reported to be preferentially expressed in lung cancer. Four target proteins were sandwiched by capture antibodies attached to microarrays and detection antibodies carried on modified gold nanoparticles. Optical signals generated by the sandwich structures were amplified by gold deposition with HAuCl4 and H2O2, and were observable by microscopy or the naked eye. The four tumor markers were subsequently measured in 106 lung cancer patients and 42 healthy persons. The assay was capable of detecting multiple biomarkers in serum sample at concentration of <1 ng mL-1 in 1 h. Combined detection of the four tumor markers highly improved the sensitivity (to 87.74%) for diagnosis of lung cancer compared with sensitivity of single markers. A rapid, highly sensitive co-detection method for multiple biomarkers based on gold nanoparticles and microarrays was developed. In clinical use, it would be expected to improve the early diagnosis of lung cancer.
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Affiliation(s)
- Wanlei Gao
- State Key Laboratory of Transducer Technology, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai, 200050, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Wentao Wang
- State Key Laboratory of Transducer Technology, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai, 200050, China; The department of Respiratory Medicine of The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, 450052, China
| | - Shihua Yao
- Changhai Hospital, Second Military Medical University, Shanghai, 200433, China
| | - Shan Wu
- State Key Laboratory of Transducer Technology, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai, 200050, China; Center of Laboratory Medicine, Affiliated Hospital of Nantong University, Nantong, Jiangsu, 226001, China
| | - Honglian Zhang
- State Key Laboratory of Transducer Technology, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai, 200050, China
| | - Jishen Zhang
- State Key Laboratory of Transducer Technology, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai, 200050, China
| | - Fengxiang Jing
- State Key Laboratory of Transducer Technology, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai, 200050, China
| | - Hongju Mao
- State Key Laboratory of Transducer Technology, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai, 200050, China
| | - Qinghui Jin
- State Key Laboratory of Transducer Technology, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai, 200050, China
| | - Hui Cong
- Center of Laboratory Medicine, Affiliated Hospital of Nantong University, Nantong, Jiangsu, 226001, China
| | - Chunping Jia
- State Key Laboratory of Transducer Technology, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai, 200050, China.
| | - Guojun Zhang
- The department of Respiratory Medicine of The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, 450052, China.
| | - Jianlong Zhao
- State Key Laboratory of Transducer Technology, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai, 200050, China
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24
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Yodmongkol S, Sutapun B, Praphanphoj V, Srikhirin T, Brandstetter T, Rühe J. Fabrication of protein microarrays for alpha fetoprotein detection by using a rapid photo-immobilization process. SENSING AND BIO-SENSING RESEARCH 2016. [DOI: 10.1016/j.sbsr.2016.01.010] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
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25
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Klapproth H, Bednar S, Baader J, Lehmann M, Freund I, Brandstetter T, Rühe J. Development of a multi-analyte CMOS sensor for point-of-care testing. SENSING AND BIO-SENSING RESEARCH 2015. [DOI: 10.1016/j.sbsr.2015.08.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
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26
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Abstract
Options for biomedical analysis continue to evolve from many fields of study, employing diverse detection and quantification methods. New technologies in this arena focus on improving the sensitivity of analysis and the speed of testing, as well as producing systems at low cost which can be used on site as a point-of-care device for telemedicine applications. In this article, the most important original experimental platforms as well as current commercial approaches to biomedical analysis are critically chosen and reviewed, covering January 2010 to January 2014. While literature is quite broad and numerous, there is clear emphasis on biological recognition and imaging for the most impactful works. The analytical approaches are discussed in terms of their utility in diagnostics and biomedical testing.
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Affiliation(s)
- Christine F Woolley
- Chemistry and Biochemistry, Arizona State University, Physical Sciences Building, Room D-102, PO Box 871604, Tempe, Arizona 85287-1604, USA.
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27
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