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Schaubeder JB, Fürk P, Amering R, Gsöls L, Ravn J, Nypelö T, Spirk S. Deciphering heterogeneous enzymatic surface reactions on xylan using surface plasmon resonance spectroscopy. Carbohydr Polym 2024; 337:122137. [PMID: 38710567 DOI: 10.1016/j.carbpol.2024.122137] [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: 10/01/2023] [Revised: 03/07/2024] [Accepted: 04/05/2024] [Indexed: 05/08/2024]
Abstract
Xylans' unique properties make it attractive for a variety of industries, including paper, food, and biochemical production. While for some applications the preservation of its natural structure is crucial, for others the degradation into monosaccharides is essential. For the complete breakdown, the use of several enzymes is required, due to its structural complexity. In fact, the specificity of enzymatically-catalyzed reactions is guided by the surface, limiting or regulating accessibility and serving structurally encoded input guiding the actions of the enzymes. Here, we investigate enzymes at surfaces rich in xylan using surface plasmon resonance spectroscopy. The influence of diffusion and changes in substrate morphology is studied via enzyme surface kinetics simulations, yielding reaction rates and constants. We propose kinetic models, which can be applied to the degradation of multilayer biopolymer films. The most advanced model was verified by its successful application to the degradation of a thin film of polyhydroxybutyrate treated with a polyhydroxybutyrate-depolymerase. The herein derived models can be employed to quantify the degradation kinetics of various enzymes on biopolymers in heterogeneous environments, often prevalent in industrial processes. The identification of key factors influencing reaction rates such as inhibition will contribute to the quantification of intricate dynamics in complex systems.
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Affiliation(s)
- Jana B Schaubeder
- Graz University of Technology, Institute of Bioproducts and Paper Technology (BPTI), Inffeldgasse 23, 8010 Graz, Austria
| | - Peter Fürk
- Graz University of Technology, Institute for Chemistry and Technology of Materials (ICTM), Stremayrgasse 9, 8010 Graz, Austria
| | - Richard Amering
- Graz University of Technology, Institute of Bioproducts and Paper Technology (BPTI), Inffeldgasse 23, 8010 Graz, Austria
| | - Lena Gsöls
- Graz University of Technology, Institute of Molecular Biotechnology, Petersgasse 14, 8010 Graz, Austria; The COMET Center, Acib GmbH, Krenngasse 37, 8010 Graz, Austria
| | - Jonas Ravn
- Chalmers University of Technology, Department of Life Sciences, 412 96 Gothenburg, Sweden
| | - Tiina Nypelö
- Chalmers University of Technology, Department of Chemistry and Chemical Engineering, 412 96 Gothenburg, Sweden; Aalto University, Department of Bioproducts and Biosystems, Vuorimiehentie 1, 02150 Espoo, Finland
| | - Stefan Spirk
- Graz University of Technology, Institute of Bioproducts and Paper Technology (BPTI), Inffeldgasse 23, 8010 Graz, Austria.
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2
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McDonough R, Williams CC, Hartley CJ, French N, Scott C, Lewis DA. Kinetic Model for the Heterogeneous Biocatalytic Reactions Using Tethered Cofactors. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2024; 40:6685-6693. [PMID: 38525517 DOI: 10.1021/acs.langmuir.3c02958] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/26/2024]
Abstract
Understanding the mechanism of interfacial enzyme kinetics is critical to the development of synthetic biological systems for the production of value-added chemicals. Here, the interfacial kinetics of the catalysis of β-nicotinamide adenine dinucleotide (NAD+)-dependent enzymes acting on NAD+ tethered to the surface of silica nanoparticles (SiNPs) has been investigated using two complementary and supporting kinetic approaches: enzyme excess and reactant (NAD+) excess. Kinetic models developed for these two approaches characterize several critical reaction steps including reversible enzyme adsorption, complexation, decomplexation, and catalysis of the surface-bound enzyme/NAD+ complex. The analysis reveals a concentrating effect resulting in a very high local concentration of enzyme and cofactor on the particle surface, in which the enzyme is saturated by surface-bound NAD, facilitating a rate enhancement of enzyme/NAD+ complexation and catalysis. This resulted in high enzyme efficiency within the tethered NAD+ system compared to that of the free enzyme/NAD+ system, which increases with decreasing enzyme concentration. The role of enzyme adsorption onto solid substrates with a tethered catalyst (such as NAD+) has potential for creating highly efficient flow biocatalytic systems.
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Affiliation(s)
- Rowan McDonough
- Institute for Nanoscale Science and Technology, School of Chemical and Physical Sciences, Flinders University, Bedford Park, SA 5042, Australia
| | | | | | - Nigel French
- CSIRO Environment, Black Mountain, ACT 2601, Australia
| | - Colin Scott
- CSIRO Environment, Black Mountain, ACT 2601, Australia
| | - David A Lewis
- Institute for Nanoscale Science and Technology, School of Chemical and Physical Sciences, Flinders University, Bedford Park, SA 5042, Australia
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Jang SJ, Kim TH. Triple multivalent aptamers within DNA tetrahedron on reduced graphene oxide electrode: Unlocking enhanced sensitivity and accelerated reactions in electrochemical sensing. Biosens Bioelectron 2024; 249:116039. [PMID: 38241797 DOI: 10.1016/j.bios.2024.116039] [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: 12/09/2023] [Revised: 01/11/2024] [Accepted: 01/12/2024] [Indexed: 01/21/2024]
Abstract
DNA nanostructures are emerging as promising biosensing platforms due to their programmability, predictable assembly, and compatibility with aptamers for enhanced selectivity. This study focuses on a triple-multivalent aptamer (tApt) complex immobilized on a tetrahedral DNA nanostructure (TDN) and integrated with an electrochemically reduced graphene oxide (ERGO) electrode for highly sensitive mercury ion (Hg2+) detection. Compared to a linear multivalent aptamer-modified electrode (S2/ERGO-GCE), the 3D tApt/ERGO-GCE aptasensor exhibits superior sensitivity, signal amplification, and reaction kinetics. The tApt/ERGO-GCE sensor achieves an exceptional limit of detection (LOD) of 4.1 zM, surpassing the LOD of 0.71 fM for S2/ERGO-GCE. Additionally, the tApt/ERGO-GCE sensor demonstrates faster response times, with a half-saturation time (T1/2) of 6 minutes compared to 17 minutes for S2/ERGO/GCE. The 3D tApt aptamer's superior performance is attributed to its tetrahedral DNA structure integrated on ERGO, providing multiple aptamer binding sites, facilitating oriented immobilization on the electrode surface, and enhancing analyte capture and concentration. In contrast, the linear S2 aptamers lack rigidity, resulting in a disordered orientation on the electrode surface, hindering efficient Hg2+ binding and reducing target molecule binding efficiency. This study underscores the potential of triple-multivalent aptamer-based nanostructures for ultrasensitive and rapid biosensing applications. The tApt/ERGO-GCE aptasensor's exceptional sensitivity, signal amplification, and reaction kinetics make it a promising tool for Hg2+ detection and other biosensing applications.
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Affiliation(s)
- Seung Joo Jang
- Department of Chemistry, Soonchunhyang University, Asan 31538, Republic of Korea
| | - Tae Hyun Kim
- Department of Chemistry, Soonchunhyang University, Asan 31538, Republic of Korea.
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Novikova TS, Ermakov EA, Kostina EV, Sinyakov AN, Sizikov AE, Nevinsky GA, Buneva VN. Hydrolysis of Oligodeoxyribonucleotides on the Microarray Surface and in Solution by Catalytic Anti-DNA Antibodies in Systemic Lupus Erythematosus. Curr Issues Mol Biol 2023; 45:9887-9903. [PMID: 38132463 PMCID: PMC10742339 DOI: 10.3390/cimb45120617] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2023] [Revised: 11/23/2023] [Accepted: 12/06/2023] [Indexed: 12/23/2023] Open
Abstract
Anti-DNA antibodies are known to be classical serological hallmarks of systemic lupus erythematosus (SLE). In addition to high-affinity antibodies, the autoantibody pool also contains natural catalytic anti-DNA antibodies that recognize and hydrolyze DNA. However, the specificity of such antibodies is uncertain. In addition, DNA binding to a surface such as the cell membrane, can also affect its recognition by antibodies. Here, we analyzed the hydrolysis of short oligodeoxyribonucleotides (ODNs) immobilized on the microarray surface and in solution by catalytic anti-DNA antibodies from SLE patients. It has been shown that IgG antibodies from SLE patients hydrolyze ODNs more effectively both in solution and on the surface, compared to IgG from healthy individuals. The data obtained indicate a more efficient hydrolysis of ODNs in solution than immobilized ODNs on the surface. In addition, differences in the specificity of recognition and hydrolysis of certain ODNs by anti-DNA antibodies were revealed, indicating the formation of autoantibodies to specific DNA motifs in SLE. The data obtained expand our understanding of the role of anti-DNA antibodies in SLE. Differences in the recognition and hydrolysis of surface-tethered and dissolved ODNs need to be considered in DNA microarray applications.
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Affiliation(s)
- Tatiana S. Novikova
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences, 630090 Novosibirsk, Russia
- Department of Natural Sciences, Novosibirsk State University, 630090 Novosibirsk, Russia
| | - Evgeny A. Ermakov
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences, 630090 Novosibirsk, Russia
- Department of Natural Sciences, Novosibirsk State University, 630090 Novosibirsk, Russia
| | - Elena V. Kostina
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences, 630090 Novosibirsk, Russia
| | - Alexander N. Sinyakov
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences, 630090 Novosibirsk, Russia
| | - Alexey E. Sizikov
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences, 630090 Novosibirsk, Russia
- Institute of Clinical Immunology, Siberian Branch of the Russian Academy of Sciences, 630099 Novosibirsk, Russia
| | - Georgy A. Nevinsky
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences, 630090 Novosibirsk, Russia
- Department of Natural Sciences, Novosibirsk State University, 630090 Novosibirsk, Russia
| | - Valentina N. Buneva
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences, 630090 Novosibirsk, Russia
- Department of Natural Sciences, Novosibirsk State University, 630090 Novosibirsk, Russia
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Xylan-cellulose thin film platform for assessing xylanase activity. Carbohydr Polym 2022; 294:119737. [DOI: 10.1016/j.carbpol.2022.119737] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Revised: 06/01/2022] [Accepted: 06/12/2022] [Indexed: 11/18/2022]
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Ahmad S, Hossain MN, Ahmadi S, Kerman K, Kraatz HB. Electrochemical distinction of neuronal and neuroblastoma cells via the phosphorylation of the cellular extracellular membrane. Anal Biochem 2021; 645:114434. [PMID: 34785194 DOI: 10.1016/j.ab.2021.114434] [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: 09/01/2020] [Revised: 10/10/2021] [Accepted: 10/21/2021] [Indexed: 11/20/2022]
Abstract
In this contribution we establish a proof of concept method for monitoring, quantifying and differentiating the extracellular phosphorylation of Human SHSY5Y undifferentiated neuronal cells and neuroblastoma cells by three prominent ectokinases PKA, PKC and Src. Herein it is demonstrated that a combination of different experimental techniques, including fluroesence microscopy, quartz crystal microscopy (QCM) and electrochemistry, can be used to detect extracellular phosphorylation levels of neuronal and neuroblastoma cells. Phosphorylation profiles of the three ectokinases, PKA, PKC and Src, were investigated using fluorescence microscopy and the number of phosphorylation sites per kinase was estimated using QCM. Finally, the phosphorylation of the extracellular membrane was determined using electrochemistry. Our results clearly demonstrate that the extracellular phosphorylation of neuronal cells differs significantly in terms of its phosphorylation profile from diseased neuroblastoma cells and the strength of surface electrochemical techniques in the differentiation process. We reveal that using electrochemistry, the percent compositions of neuronal and neuroblastoma cells can also be identified.
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Affiliation(s)
- S Ahmad
- Department of Physical and Environmental Sciences, University of Toronto Scarborough, 1265 Military Trail, Toronto, M1C 1A4, Canada; Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, M5S 3H6, Canada
| | - M N Hossain
- Department of Physical and Environmental Sciences, University of Toronto Scarborough, 1265 Military Trail, Toronto, M1C 1A4, Canada; Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, M5S 3H6, Canada
| | - S Ahmadi
- Department of Physical and Environmental Sciences, University of Toronto Scarborough, 1265 Military Trail, Toronto, M1C 1A4, Canada; Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, M5S 3H6, Canada
| | - K Kerman
- Department of Physical and Environmental Sciences, University of Toronto Scarborough, 1265 Military Trail, Toronto, M1C 1A4, Canada; Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, M5S 3H6, Canada
| | - H-B Kraatz
- Department of Physical and Environmental Sciences, University of Toronto Scarborough, 1265 Military Trail, Toronto, M1C 1A4, Canada; Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, M5S 3H6, Canada.
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Vogel K, Wei R, Pfaff L, Breite D, Al-Fathi H, Ortmann C, Estrela-Lopis I, Venus T, Schulze A, Harms H, Bornscheuer UT, Maskow T. Enzymatic degradation of polyethylene terephthalate nanoplastics analyzed in real time by isothermal titration calorimetry. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 773:145111. [PMID: 33940717 DOI: 10.1016/j.scitotenv.2021.145111] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Revised: 01/06/2021] [Accepted: 01/06/2021] [Indexed: 06/12/2023]
Abstract
Plastics are globally used for a variety of benefits. As a consequence of poor recycling or reuse, improperly disposed plastic waste accumulates in terrestrial and aquatic ecosystems to a considerable extent. Large plastic waste items become fragmented to small particles through mechanical and (photo)chemical processes. Particles with sizes ranging from millimeter (microplastics, <5 mm) to nanometer (nanoplastics, NP, <100 nm) are apparently persistent and have adverse effects on ecosystems and human health. Current research therefore focuses on whether and to what extent microorganisms or enzymes can degrade these NP. In this study, we addressed the question of what information isothermal titration calorimetry, which tracks the heat of reaction of the chain scission of a polyester, can provide about the kinetics and completeness of the degradation process. The majority of the heat represents the cleavage energy of the ester bonds in polymer backbones providing real-time kinetic information. Calorimetry operates even in complex matrices. Using the example of the cutinase-catalyzed degradation of polyethylene terephthalate (PET) nanoparticles, we found that calorimetry (isothermal titration calorimetry-ITC) in combination with thermokinetic models is excellently suited for an in-depth analysis of the degradation processes of NP. For instance, we can separately quantify i) the enthalpy of surface adsorption ∆AdsH = 129 ± 2 kJ mol-1, ii) the enthalpy of the cleavage of the ester bonds ∆EBH = -58 ± 1.9 kJ mol-1 and the apparent equilibrium constant of the enzyme substrate complex K = 0.046 ± 0.015 g L-1. It could be determined that the heat production of PET NP degradation depends to 95% on the reaction heat and only to 5% on the adsorption heat. The fact that the percentage of cleaved ester bonds (η = 12.9 ± 2.4%) is quantifiable with the new method is of particular practical importance. The new method promises a quantification of enzymatic and microbial adsorption to NP and their degradation in mimicked real-world aquatic conditions.
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Affiliation(s)
- Kristina Vogel
- Department of Environmental Microbiology, Helmholtz-Centre for Environmental Research - UFZ, Permoserstraße 15, D-04318 Leipzig, Germany; Institute for Drug Discovery, Leipzig University Medical School, Leipzig University, Bruederstr, 34, D-04103 Leipzig, Germany
| | - Ren Wei
- Department of Biotechnology and Enzyme Catalysis, Institute for Biochemistry, University of Greifswald, Felix-Hausdorff-Str. 4, D-17487 Greifswald, Germany.
| | - Lara Pfaff
- Department of Biotechnology and Enzyme Catalysis, Institute for Biochemistry, University of Greifswald, Felix-Hausdorff-Str. 4, D-17487 Greifswald, Germany
| | - Daniel Breite
- Leibniz Institute of Surface Engineering (IOM), Permoserstraße 15, D-04318 Leipzig, Germany
| | - Hassan Al-Fathi
- Department of Environmental Microbiology, Helmholtz-Centre for Environmental Research - UFZ, Permoserstraße 15, D-04318 Leipzig, Germany
| | | | - Irina Estrela-Lopis
- Institute for Medical Physics and Biophysics, Medical Faculty, Leipzig University, Härtelstr, 16-18, D-04107 Leipzig, Germany
| | - Tom Venus
- Institute for Medical Physics and Biophysics, Medical Faculty, Leipzig University, Härtelstr, 16-18, D-04107 Leipzig, Germany
| | - Agnes Schulze
- Leibniz Institute of Surface Engineering (IOM), Permoserstraße 15, D-04318 Leipzig, Germany
| | - Hauke Harms
- Department of Environmental Microbiology, Helmholtz-Centre for Environmental Research - UFZ, Permoserstraße 15, D-04318 Leipzig, Germany
| | - Uwe T Bornscheuer
- Department of Biotechnology and Enzyme Catalysis, Institute for Biochemistry, University of Greifswald, Felix-Hausdorff-Str. 4, D-17487 Greifswald, Germany
| | - Thomas Maskow
- Department of Environmental Microbiology, Helmholtz-Centre for Environmental Research - UFZ, Permoserstraße 15, D-04318 Leipzig, Germany.
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Label-Free Fluorescence Molecular Beacon Probes Based on G-Triplex DNA and Thioflavin T for Protein Detection. Molecules 2021; 26:molecules26102962. [PMID: 34067563 PMCID: PMC8156537 DOI: 10.3390/molecules26102962] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Revised: 05/07/2021] [Accepted: 05/11/2021] [Indexed: 11/16/2022] Open
Abstract
Protein detection plays an important role in biological and biomedical sciences. The immunoassay based on fluorescence labeling has good specificity but a high labeling cost. Herein, on the basis of G-triplex molecular beacon (G3MB) and thioflavin T (ThT), we developed a simple and label-free biosensor for protein detection. The biotin and streptavidin were used as model enzymes. In the presence of target streptavidin (SA), the streptavidin hybridized with G3MB-b (biotin-linked-G-triplex molecular beacon) perfectly and formed larger steric hindrance, which hindered the hydrolysis of probes by exonuclease III (Exo III). In the absence of target streptavidin, the exonuclease III successively cleaved the stem of G3MB-b and released the G-rich sequences which self-assembled into a G-triplex and subsequently activated the fluorescence signal of thioflavin T. Compared with the traditional G-quadruplex molecular beacon (G4MB), the G3MB only needed a lower dosage of exonuclease III and a shorter reaction time to reach the optimal detection performance, because the concise sequence of G-triplex was good for the molecular beacon design. Moreover, fluorescence experiment results exhibited that the G3MB-b had good sensitivity and specificity for streptavidin detection. The developed label-free biosensor provides a valuable and general platform for protein detection.
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Ahmad S, Hossain MN, Ahmadi S, Kerman K, Kraatz HB. Electrochemical detection of neuronal extracellular phosphorylation by PKA, PKC and Src. Anal Biochem 2020; 608:113892. [PMID: 32810472 DOI: 10.1016/j.ab.2020.113892] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Revised: 07/21/2020] [Accepted: 07/24/2020] [Indexed: 11/30/2022]
Abstract
The focus of this work described here is to establish a method for monitoring and quantifying the extracellular phosphorylation of Human SHSY5Y undifferentiated neuronal cells by three ectokinases PKA, PKC and Src; these are kinases that are known to be present in the extracellular matrix. Here is demonstrated that a combination of different experimental techniques, including microscopy and electrochemistry, can be used to detect extracellular phosphorylations. Phosphorylation profiles of the three ectokinases, PKA, PKC and Src, were investigated using fluorescence microscopy and the number of phosphorylation sites per kinase was estimated using QCM. Finally, the phosphorylation of the extracellular membrane was determined using electrochemistry. Our results clearly demonstrate the extracellular phosphorylation of neuronal cells and the strength of surface electrochemical techniques in the investigation of cellular phosphorylation.
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Affiliation(s)
- S Ahmad
- Department of Physical and Environmental Sciences, University of Toronto Scarborough, 1265 Military Trail, Toronto, M1C 1A4, Canada; Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, M5S 3H6, Canada
| | - M N Hossain
- Department of Physical and Environmental Sciences, University of Toronto Scarborough, 1265 Military Trail, Toronto, M1C 1A4, Canada; Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, M5S 3H6, Canada
| | - S Ahmadi
- Department of Physical and Environmental Sciences, University of Toronto Scarborough, 1265 Military Trail, Toronto, M1C 1A4, Canada; Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, M5S 3H6, Canada
| | - K Kerman
- Department of Physical and Environmental Sciences, University of Toronto Scarborough, 1265 Military Trail, Toronto, M1C 1A4, Canada; Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, M5S 3H6, Canada
| | - H-B Kraatz
- Department of Physical and Environmental Sciences, University of Toronto Scarborough, 1265 Military Trail, Toronto, M1C 1A4, Canada; Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, M5S 3H6, Canada.
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10
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Electrochemical studies of human nAChR a7 subunit phosphorylation by kinases PKA, PKC and Src. Anal Biochem 2019; 574:46-56. [DOI: 10.1016/j.ab.2019.03.012] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Revised: 03/19/2019] [Accepted: 03/19/2019] [Indexed: 12/19/2022]
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Enzymatic removal of protein fouling from self-assembled cellulosic nanofilms: experimental and modeling studies. EUROPEAN BIOPHYSICS JOURNAL: EBJ 2018; 47:951-960. [DOI: 10.1007/s00249-018-1320-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2018] [Revised: 06/09/2018] [Accepted: 07/04/2018] [Indexed: 10/28/2022]
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Castañeda AD, Brenes NJ, Kondajji A, Crooks RM. Detection of microRNA by Electrocatalytic Amplification: A General Approach for Single-Particle Biosensing. J Am Chem Soc 2017; 139:7657-7664. [DOI: 10.1021/jacs.7b03648] [Citation(s) in RCA: 100] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Alma D. Castañeda
- Department of Chemistry and
Center for Electrochemistry, The University of Texas at Austin, 105 E. 24th Street, Stop A5300, Austin, Texas 78712-1224, United States
| | - Nicholas J. Brenes
- Department of Chemistry and
Center for Electrochemistry, The University of Texas at Austin, 105 E. 24th Street, Stop A5300, Austin, Texas 78712-1224, United States
| | - Aditya Kondajji
- Department of Chemistry and
Center for Electrochemistry, The University of Texas at Austin, 105 E. 24th Street, Stop A5300, Austin, Texas 78712-1224, United States
| | - Richard M. Crooks
- Department of Chemistry and
Center for Electrochemistry, The University of Texas at Austin, 105 E. 24th Street, Stop A5300, Austin, Texas 78712-1224, United States
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Lee HK, Heo J, Myung S, Shin IS, Kim TH. Homogeneous Electrochemical Assay for Real-time Monitoring of Exonuclease III Activity Based on a Graphene Monolayer. ELECTROANAL 2017. [DOI: 10.1002/elan.201700006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
- Heon-Kyu Lee
- Department of Chemistry; Soonchunhyang University; Asan 31538 Republic of Korea
| | - Jihye Heo
- Department of Chemistry; Soonchunhyang University; Asan 31538 Republic of Korea
| | - Sung Myung
- Thin Film Materials Research Center; Korea Research Institute of Chemical Technology; Daejeon 34114 Republic of Korea
| | - Ik-Soo Shin
- Department of Chemistry; Soongsil University; Seoul 06978 Republic of Korea
| | - Tae Hyun Kim
- Department of Chemistry; Soonchunhyang University; Asan 31538 Republic of Korea
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14
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Castañeda AD, Robinson DA, Stevenson KJ, Crooks RM. Electrocatalytic amplification of DNA-modified nanoparticle collisions via enzymatic digestion. Chem Sci 2016; 7:6450-6457. [PMID: 28451102 PMCID: PMC5356041 DOI: 10.1039/c6sc02165d] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2016] [Accepted: 06/22/2016] [Indexed: 01/04/2023] Open
Abstract
We report a new and general approach that will be useful for adapting the method of electrocatalytic amplification (ECA) to biosensing applications. In ECA, individual collisions of catalytic nanoparticles with a noncatalytic electrode surface lead to bursts of current. In the work described here, the current arises from catalytic electrooxidation of N2H4 at the surface of platinum nanoparticles (PtNPs). The problem with using ECA for biosensing applications heretofore, is that it is necessary to immobilize a receptor, such as DNA (as in the case here) or an antibody on the PtNP surface. This inactivates the colliding NP, however, and leads to very small collision signatures. In the present article, we show that single-stranded DNA (ssDNA) present on the PtNP surface can be detected by selectively removing a fraction of the ssDNA using the enzyme Exonuclease I (Exo I). About half of the current associated with collisions of naked PtNPs can be recovered from fully passivated PtNPs after exposure to Exo I. Experiments carried out using both Au and Hg ultramicroelectrodes reveal some mechanistic aspects of the collision process before and after treatment of the ssDNA-modified PtNPs with Exo I.
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Affiliation(s)
- Alma D Castañeda
- Department of Chemistry , Center for Electrochemistry, and the Center for Nano- and Molecular Science and Technology , The University of Texas at Austin , 105 E. 24th St., Stop A5300 , Austin , TX 78712-1224 , USA . ; Tel: +1-512-475-8674
| | - Donald A Robinson
- Department of Chemistry , Center for Electrochemistry, and the Center for Nano- and Molecular Science and Technology , The University of Texas at Austin , 105 E. 24th St., Stop A5300 , Austin , TX 78712-1224 , USA . ; Tel: +1-512-475-8674
| | - Keith J Stevenson
- Department of Chemistry , Center for Electrochemistry, and the Center for Nano- and Molecular Science and Technology , The University of Texas at Austin , 105 E. 24th St., Stop A5300 , Austin , TX 78712-1224 , USA . ; Tel: +1-512-475-8674
| | - Richard M Crooks
- Department of Chemistry , Center for Electrochemistry, and the Center for Nano- and Molecular Science and Technology , The University of Texas at Austin , 105 E. 24th St., Stop A5300 , Austin , TX 78712-1224 , USA . ; Tel: +1-512-475-8674
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Fasoli J, Corn RM. Surface Enzyme Chemistries for Ultrasensitive Microarray Biosensing with SPR Imaging. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2015; 31:9527-9536. [PMID: 25641598 PMCID: PMC4564839 DOI: 10.1021/la504797z] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2014] [Revised: 01/30/2015] [Indexed: 06/01/2023]
Abstract
The sensitivity and selectivity of surface plasmon resonance imaging (SPRI) biosensing with nucleic acid microarrays can be greatly enhanced by exploiting various nucleic acid ligases, nucleases, and polymerases that manipulate the surface-bound DNA and RNA. We describe here various examples from each of these different classes of surface enzyme chemistries that have been incorporated into novel detection strategies that either drastically enhance the sensitivity of or create uniquely selective methods for the SPRI biosensing of proteins and nucleic acids. A dual-element generator-detector microarray approach that couples a bioaffinity adsorption event on one microarray element to nanoparticle-enhanced SPRI measurements of nucleic acid hybridization adsorption on a different microarray element is used to quantitatively detect DNA, RNA, and proteins at femtomolar concentrations. Additionally, this dual-element format can be combined with the transcription and translation of RNA from surface-bound double-stranded DNA (dsDNA) templates for the on-chip multiplexed biosynthesis of aptamer and protein microarrays in a microfluidic format; these microarrays can be immediately used for real-time SPRI bioaffinity sensing measurements.
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17
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Dutta D, Pulsipher A, Luo W, Yousaf MN. PI3 kinase enzymology on fluid lipid bilayers. Analyst 2014; 139:5127-33. [PMID: 25133271 DOI: 10.1039/c4an00998c] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
We report the use of fluid lipid bilayer membrane as a model platform to study the influence of the bilayer microenvironment and composition on the enzymology in membrane. As a model system we determined the enzyme kinetics on membranes for the transformation of bilayers containing phosphoinositol(4,5)-bisphosphate (PI(4,5)P2) to phosphoinositol(3,4,5)-trisphosphate (PI(3,4,5)P3) by the enzyme phosphoinositol-3-kinase (PI3K) using radiolabeled ATP. The activity of the enzyme was monitored as a function of the radioactivity incorporated within the bilayer. The transformation of PI(4,5)P2 to PI(3,4,5)P3 was determined using a mass strip assay. The fluidity of the bilayer was confirmed by Fluorescence Recovery After Photobleaching (FRAP) experiments. Kinetic simulations were performed based on Langmuir adsorption and Michaelis-Menton kinetics equations to generate the rate constants for the enzymatic reaction. The effect of cholesterol on the enzyme kinetics was studied by doping the bilayer with 1% cholesterol. This leads to significant reduction in reaction rate due to change in membrane microenvironment. This strategy provides a method to study the enzymology of various kinases and phosphatases occurring at the membrane and also how these reactions are affected by the membrane composition and surface microenvironment.
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Affiliation(s)
- Debjit Dutta
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
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18
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Šípová H, Homola J. Surface plasmon resonance sensing of nucleic acids: a review. Anal Chim Acta 2013; 773:9-23. [PMID: 23561902 DOI: 10.1016/j.aca.2012.12.040] [Citation(s) in RCA: 137] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2012] [Revised: 12/19/2012] [Accepted: 12/21/2012] [Indexed: 12/12/2022]
Abstract
Biosensors based on surface plasmon resonance (SPR) have become a central tool for the investigation and quantification of biomolecules and their interactions. Nucleic acids (NAs) play a vital role in numerous biological processes and therefore have been one of the major groups of biomolecules targeted by the SPR biosensors. This paper discusses the advances of NA SPR biosensor technology and reviews its applications both in the research of molecular interactions involving NAs (NA-NA, NA-protein, NA-small molecule), as well as for the field of bioanalytics in the areas of food safety, medical diagnosis and environmental monitoring.
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Affiliation(s)
- Hana Šípová
- Institute of Photonics and Electronics, Academy of Sciences of the Czech Republic, Chaberská 57, Prague, Czech Republic
| | - Jiří Homola
- Institute of Photonics and Electronics, Academy of Sciences of the Czech Republic, Chaberská 57, Prague, Czech Republic.
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19
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Anne A, Demaille C. Kinetics of enzyme action on surface-attached substrates: a practical guide to progress curve analysis in any kinetic situation. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2012; 28:14665-14671. [PMID: 22978617 DOI: 10.1021/la3030827] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
In the present work, exact kinetic equations describing the action of an enzyme in solution on a substrate attached to a surface have been derived in the framework of the Michaelis-Menten mechanism but without resorting to the often-used steady-state approximation. The here-derived kinetic equations are cast in a workable format, allowing us to introduce a simple and universal procedure for the quantitative analysis of enzyme surface kinetics that is valid for any kinetic situation. The results presented here should allow experimentalists studying the kinetics of enzyme action on immobilized substrates to analyze their data in a perfectly rigorous way.
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Affiliation(s)
- Agnès Anne
- Laboratoire d'Electrochimie Moléculaire, UMR 7591 CNRS, Université Paris Diderot, Sorbonne Paris Cité, 15 rue Jean-Antoine de Baïf, F-75205 Paris Cedex 13, France
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20
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Zelzer M, Todd SJ, Hirst AR, McDonald TO, Ulijn RV. Enzyme responsive materials: design strategies and future developments. Biomater Sci 2012; 1:11-39. [PMID: 32481995 DOI: 10.1039/c2bm00041e] [Citation(s) in RCA: 227] [Impact Index Per Article: 18.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Enzyme responsive materials (ERMs) are a class of stimuli responsive materials with broad application potential in biological settings. This review highlights current and potential future design strategies for ERMs and provides an overview of the present state of the art in the area.
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Affiliation(s)
- Mischa Zelzer
- WestCHEM, Thomas Graham Building, 295 Cathedral Street, Glasgow, G1 1XL, U.K..
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21
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Zou Q, Menegazzo N, Booksh KS. Development and Investigation of a Dual-Pad In-Channel Referencing Surface Plasmon Resonance Sensor. Anal Chem 2012; 84:7891-8. [DOI: 10.1021/ac301528z] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Qiongjing Zou
- Department
of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716, United States
| | - Nicola Menegazzo
- Department
of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716, United States
| | - Karl S. Booksh
- Department
of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716, United States
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22
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Algar WR, Malonoski A, Deschamps JR, Blanco-Canosa JB, Susumu K, Stewart MH, Johnson BJ, Dawson PE, Medintz IL. Proteolytic activity at quantum dot-conjugates: kinetic analysis reveals enhanced enzyme activity and localized interfacial "hopping". NANO LETTERS 2012; 12:3793-802. [PMID: 22731798 PMCID: PMC9354701 DOI: 10.1021/nl301727k] [Citation(s) in RCA: 95] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Recent studies show that polyvalent, ligand-modified nanoparticles provide significantly enhanced binding characteristics compared to isolated ligands. Here, we assess the ability of substrate-modified nanoparticles to provide enhanced enzymatic activity. Energy transfer assays allowed quantitative, real-time measurement of proteolytic digestion at polyvalent quantum dot-peptide conjugates. Enzymatic progress curves were analyzed using an integrated Michaelis-Menten (MM) formalism, revealing mechanistic details, including deviations from classic MM-behavior. A "hopping" mode of proteolysis at the nanoparticle was identified, confirming enhanced activity.
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Affiliation(s)
- W. Russ Algar
- Center for Bio/Molecular Science and Engineering, Code 6900
- College of Science George Mason University Fairfax, VA 22030, USA
| | | | | | - Juan B. Blanco-Canosa
- Departments of Cell Biology and Chemistry The Scripps Research Institute La Jolla, CA 92037, USA
| | - Kimihiro Susumu
- Optical Sciences Division, Code 5611 U.S. Naval Research Laboratory Washington, DC 20375, USA
| | - Michael H. Stewart
- Optical Sciences Division, Code 5611 U.S. Naval Research Laboratory Washington, DC 20375, USA
| | | | - Philip E. Dawson
- Departments of Cell Biology and Chemistry The Scripps Research Institute La Jolla, CA 92037, USA
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23
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Anne A, Chovin A, Demaille C. Optimizing electrode-attached redox-peptide systems for kinetic characterization of protease action on immobilized substrates. Observation of dissimilar behavior of trypsin and thrombin enzymes. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2012; 28:8804-8813. [PMID: 22591015 DOI: 10.1021/la301316r] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
In this work, we experimentally address the issue of optimizing gold electrode attached ferrocene (Fc)-peptide systems for kinetic measurements of protease action. Considering human α-thrombin and bovine trypsin as proteases of interest, we show that the recurring problem of incomplete cleavage of the peptide layer by these enzymes can be solved by using ultraflat template-stripped gold, instead of polished polycrystalline gold, as the Fc-peptide bearing electrode material. We describe how these fragile surfaces can be mounted in a rotating disk configuration so that enzyme mass transfer no longer limits the overall measured cleavage kinetics. Finally, we demonstrate that, once the system has been optimized, in situ real-time cyclic voltammetry monitoring of the protease action can yield high-quality kinetic data, showing no sign of interfering effects. The cleavage progress curves then closely match the Langmuirian variation expected for a kinetically controlled surface process. Global fit of the progress curves yield accurate values of the peptide cleavage rate for both trypsin and thrombin. It is shown that, whereas trypsin action on the surface-attached peptide closely follows Michaelis-Menten kinetics, thrombin displays a specific and unexpected behavior characterized by a nearly enzyme-concentration-independent cleavage rate in the subnanomolar enzyme concentration range. The reason for this behavior has still to be clarified, but its occurrence may limit the sensitivity of thrombin sensors based on Fc-peptide layers.
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Affiliation(s)
- Agnès Anne
- Laboratoire d'Electrochimie Moléculaire, UMR 7591 CNRS, Univ Paris Diderot, Sorbonne Paris Cité, 15 rue Jean-Antoine de Baïf, F-75205 Paris Cedex 13, France.
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24
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Kong DH, Jung SH, Lee ST, Kim YM, Ha KS. Monitoring of proteolytic enzyme activity using phase transition-based peptide arrays. Biosens Bioelectron 2012; 36:147-53. [DOI: 10.1016/j.bios.2012.04.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2011] [Revised: 03/18/2012] [Accepted: 04/09/2012] [Indexed: 02/01/2023]
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25
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Lee AG, Beebe DJ, Palecek SP. Quantification of kinase activity in cell lysates via photopatterned macroporous poly(ethylene glycol) hydrogel arrays in microfluidic channels. Biomed Microdevices 2012; 14:247-57. [PMID: 22069079 PMCID: PMC3299890 DOI: 10.1007/s10544-011-9602-y] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/15/2022]
Abstract
The efficacy of tyrosine kinase inhibitors (TKIs) as cancer therapeutics varies amongst individual patients as a result of patient-specific differences in molecular regulation of cancer development and progression, and acquisition of resistance to TKIs during therapy. A sensitive assay that can quantify kinase activity and predict inhibition of that activity from minimally invasive patient tissue samples may aid design of efficacious individualized TKI treatments. A microfluidic format can be useful in reducing limitations in standard protein kinase assays, including sensitivity required and low sample volume available. We present photopatterned macroporous poly(ethylene glycol) diacrylate hydrogel pillars functionalized with kinase substrates within microchannels for quantifying kinase activity in complex cellular lysates. We determined the effect of using a porogen to induce macroporosity in hydrogel pillars and showed that hydrogel poration enhanced the sensitivity of detecting Bcr-Abl activity in cell lysates by an order of magnitude. Bcr-Abl tyrosine kinase activity in K562 cell lysates could be detected from 0.01 μg/μL of cell lysate, corresponding to approximately 500 cells, using GST-Crkl immobilized in macroporous hydrogels. This device was also capable of quantifying inhibition of Bcr-Abl activity by imatinib mesylate, which demonstrates the potential to predict the biochemical response to drug inhibitors. These results indicate that microfluidic devices containing macroporous hydrogels functionalized with kinase substrates provide a promising platform for sensitive and specific quantification of kinase activity and efficacy of kinase inhibitors in cancer cell lysates.
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Affiliation(s)
- Andrew G. Lee
- Department of Chemical and Biological Engineering, University of Wisconsin - Madison, 1415 Engineering Drive, Madison, WI 53706
| | - David J. Beebe
- Department of Biomedical Engineering, University of Wisconsin – Madison, 1550 Engineering Drive, Madison, WI 53706
| | - Sean P. Palecek
- Department of Chemical and Biological Engineering, University of Wisconsin - Madison, 1415 Engineering Drive, Madison, WI 53706
- Department of Biomedical Engineering, University of Wisconsin – Madison, 1550 Engineering Drive, Madison, WI 53706
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26
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Detection of mismatched caspase-3 DNA oligonucleotides with an SPR biosensor following amplification by Taq polymerase. Mikrochim Acta 2012. [DOI: 10.1007/s00604-012-0799-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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27
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D’Agata R, Spoto G. Surface Plasmon Resonance-Based Methods. DETECTION OF NON-AMPLIFIED GENOMIC DNA 2012. [DOI: 10.1007/978-94-007-1226-3_9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
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28
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Real-time monitoring of matrix metalloproteinase-9 collagenolytic activity with a surface plasmon resonance biosensor. Anal Biochem 2011; 419:53-60. [DOI: 10.1016/j.ab.2011.07.031] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2011] [Revised: 07/23/2011] [Accepted: 07/25/2011] [Indexed: 11/18/2022]
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29
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Seefeld TH, Zhou WJ, Corn RM. Rapid microarray detection of DNA and proteins in microliter volumes with surface plasmon resonance imaging measurements. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2011; 27:6534-40. [PMID: 21488682 PMCID: PMC3093654 DOI: 10.1021/la200649n] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
A four-chamber microfluidic biochip is fabricated for the rapid detection of multiple proteins and nucleic acids from microliter volume samples with the technique of surface plasmon resonance imaging (SPRI). The 18 mm × 18 mm biochip consists of four 3 μL microfluidic chambers attached to an SF10 glass substrate, each of which contains three individually addressable SPRI gold thin film microarray elements. The 12-element (4 × 3) SPRI microarray consists of gold thin film spots (1 mm(2) area; 45 nm thickness), each in individually addressable 0.5 μL volume microchannels. Microarrays of single-stranded DNA and RNA (ssDNA and ssRNA, respectively) are fabricated by either chemical and/or enzymatic attachment reactions in these microchannels; the SPRI microarrays are then used to detect femtomole amounts (nanomolar concentrations) of DNA and proteins (ssDNA binding protein and thrombin via aptamer-protein bioaffinity interactions). Microarrays of ssRNA microarray elements are also used for the ultrasensitive detection of zeptomole amounts (femtomolar concentrations) of DNA via the technique of RNase H-amplified SPRI. Enzymatic removal of ssRNA from the surface due to the hybridization adsorption of target ssDNA is detected as a reflectivity decrease in the SPR imaging measurements. The observed reflectivity loss is proportional to the log of the target ssDNA concentration with a detection limit of 10 fM or 30 zeptomoles (18 000 molecules). This enzymatic amplified ssDNA detection method is not limited by diffusion of ssDNA to the interface, and thus is extremely fast, requiring only 200 s in the microliter volume format.
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30
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Renckens T, Almeida A, Damen M, Kreutzer M, Mul G. Product desorption limitations in selective photocatalytic oxidation. Catal Today 2010. [DOI: 10.1016/j.cattod.2009.12.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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31
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Clé C, Martin C, Field RA, Kuzmič P, Bornemann S. Detection of enzyme-catalyzed polysaccharide synthesis on surfaces. BIOCATAL BIOTRANSFOR 2009. [DOI: 10.3109/10242420903388744] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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32
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Mugherli L, Burchak O, Balakireva L, Thomas A, Chatelain F, Balakirev M. In Situ Assembly and Screening of Enzyme Inhibitors with Surface-Tension Microarrays. Angew Chem Int Ed Engl 2009; 48:7639-44. [DOI: 10.1002/anie.200901139] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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33
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Mugherli L, Burchak O, Balakireva L, Thomas A, Chatelain F, Balakirev M. In Situ Assembly and Screening of Enzyme Inhibitors with Surface-Tension Microarrays. Angew Chem Int Ed Engl 2009. [DOI: 10.1002/ange.200901139] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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34
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Frisk ML, Tepp WH, Johnson EA, Beebe DJ. Self-assembled peptide monolayers as a toxin sensing mechanism within arrayed microchannels. Anal Chem 2009; 81:2760-7. [PMID: 19253949 PMCID: PMC2760437 DOI: 10.1021/ac802707u] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A sensor for the lethal bacterial enzyme, botulinum neurotoxin type A (BoNT/A), was developed using self-assembled monolayers (SAMs). SAMs consisting of an immobilized synthetic peptide that mimicked the toxin's in vivo SNAP-25 protein substrate were formed on Au and interfaced with arrayed microfluidic channels. Efforts to optimize SAM composition and assay conditions for greatest reaction efficiency and sensitivity are described in detail. Channel design provided facile fluid manipulation, sample incubation, analyte concentration, and fluorescence detection all within a single microfluidic channel, thus avoiding sample transfer and loss. Peptide SAMs were exposed to varying concentrations of BoNT/A or its catalytic light chain (ALC), resulting in enzymatic cleavage of the peptide substrate from the surface. Fluorescence detection was achieved down to 20 pg/mL ALC and 3 pg/mL BoNT/A in 3 h. Toxin sensing was also accomplished in vegetable soup, demonstrating practicality of the method. The modular design of this microfluidic SAM platform allows for extension to sensing other toxins that operate via enzymatic cleavage, such as the remaining BoNT serotypes B-G, anthrax, and tetanus toxin.
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Affiliation(s)
- Megan L. Frisk
- Department of Chemistry, University of Wisconsin, Madison, Wisconsin 53706
| | - William H. Tepp
- Department of Food Microbiology and Toxicology, Department of Bacteriology, University of Wisconsin, Madison, Wisconsin 53706
| | - Eric A. Johnson
- Department of Food Microbiology and Toxicology, Department of Bacteriology, University of Wisconsin, Madison, Wisconsin 53706
| | - David J. Beebe
- Department of Biomedical Engineering, University of Wisconsin, Madison, Wisconsin 53706
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35
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Hardesty JO, Cascão-Pereira L, Kellis JT, Robertson CR, Frank CW. Enzymatic proteolysis of a surface-bound alpha-helical polypeptide. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2008; 24:13944-13956. [PMID: 19360953 DOI: 10.1021/la8020386] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
In this work, we studied the interactions of enzymes with model substrate surfaces using label-free techniques. Our model system was based on serine proteases (a class of enzymes that digests proteins) and surface-bound polypeptide substrates. While previous studies have focused on bulk media factors such as pH, ionic strength, and surfactants, this study focuses on the role of the surface-bound substrate itself. In particular, we assess how the substrate density of a polypeptide with an alpha-helical secondary structure influences surface reactivity. An alpha-helical secondary structure was chosen based on literature indicating that stable alpha-helices can resist enzymatic digestion. To investigate the protease resistance of a surface-bound a-helix, we designed an a-helical polypeptide (SS-polypeptide, where SS = disulfide), used it to form films of varying surface coverage and then measured responses of the films to enzymatic exposure. Using quartz-crystal microbalance with dissipation (QCM-D), angle-resolved X-ray photoelectron spectroscopy (AR-XPS), grazing-angle infrared spectroscopy (GAIRS), and other techniques, we characterized the degradation of films to determine how the lateral packing density of the surface-bound SS-polypeptide substrate affected surface proteolysis. Characterization of pure SS-polypeptide films indicated dense packing of helices that maintained their helical structure and were generally oriented normal to the surface. We found that films of pure SS-polypeptide significantly resisted enzymatic digestion, while incorporation of very minor amounts of a diluent in such films resulted in rapid digestion. In part, this may be due to the need for the enzyme to bind several peptides along the peptide substrate within the cleft for digestion to occur. Only SS-polypeptide films that were densely packed and did not permit catalytic access to multiple peptides (e.g., terminal peptides only) were resistant to enzymatic proteolysis.
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Affiliation(s)
- Jasper O Hardesty
- Biochemistry Department, Genencor International, Palo Alto, California 94304, USA
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36
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Foose LL, Blanch HW, Radke CJ. Kinetics of adsorption and proteolytic cleavage of a multilayer ovalbumin film by subtilisin Carlsberg. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2008; 24:7388-7393. [PMID: 18564867 DOI: 10.1021/la8007014] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Adsorption and proteolytic activity of the enzyme subtilisin Carlsberg have been studied on an immobilized, multilayer ovalbumin film. The cross-linked multilayer substrate permits protease adsorption to be examined unencumbered by the surface inhomogeneity typically observed in monolayer studies of protease surface kinetics. Decline of the protein film was measured over time using ellipsometry. Resulting kinetic data as a function of aqueous enzyme concentration and temperature were well fit by a Langmuir-Michaelis-Menten model for surface proteolysis. We observed that both the protein degradation kinetics and the in situ adsorption data were well described by the proposed model. The temperature dependence of the kinetic rate parameter yielded an activation energy of 12 kcal/mol. Further, the apparent Langmuir adsorption equilibrium constant of the enzyme at the protein/aqueous interface was 0.11 L/mg at 22 degrees C, 0.034 L/mg at 36 degrees C, and 0.011 L/mg at 50 degrees C. Although enzyme adsorption at a given aqueous enzyme concentration decreased at higher temperature, the enzyme cleaved the substrate more rapidly, leading to a net increase in the ovalbumin film degradation rate. We observed that the maximum enzyme coverage on the immobilized protein surface was approximately 40% of a close-packed monolayer at ambient temperature (22 degrees C).
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Affiliation(s)
- Ladan L Foose
- Department of Chemical Engineering, University of California, Berkeley, California 94720, USA
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37
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Chen YT, Hsu CL, Hou SY. Detection of single-nucleotide polymorphisms using gold nanoparticles and single-strand-specific nucleases. Anal Biochem 2008; 375:299-305. [PMID: 18211817 DOI: 10.1016/j.ab.2007.12.036] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2007] [Revised: 12/21/2007] [Accepted: 12/21/2007] [Indexed: 12/24/2022]
Abstract
The current study reports an assay approach that can detect single-nucleotide polymorphisms (SNPs) and identify the position of the point mutation through a single-strand-specific nuclease reaction and a gold nanoparticle assembly. The assay can be implemented via three steps: a single-strand-specific nuclease reaction that allows the enzyme to truncate the mutant DNA; a purification step that uses capture probe-gold nanoparticles and centrifugation; and a hybridization reaction that induces detector probe-gold nanoparticles, capture probe-gold nanoparticles, and the target DNA to form large DNA-linked three-dimensional aggregates of gold nanoparticles. At high temperature (63 degrees C in the current case), the purple color of the perfect match solution would not change to red, whereas a mismatched solution becomes red as the assembled gold nanoparticles separate. Using melting analysis, the position of the point mutation could be identified. This assay provides a convenient colorimetric detection that enables point mutation identification without the need for expensive mass spectrometry. To our knowledge, this is the first report concerning SNP detection based on a single-strand-specific nuclease reaction and a gold nanoparticle assembly.
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Affiliation(s)
- Yen-Ting Chen
- Institute of Biotechnology, National Taipei University of Technology, Taipei 106, Taiwan
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38
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Hansen RR, Sikes HD, Bowman CN. Visual detection of labeled oligonucleotides using visible-light-polymerization-based amplification. Biomacromolecules 2007; 9:355-62. [PMID: 18052028 DOI: 10.1021/bm700672z] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
DNA biochip technology holds potential for highly parallel, rapid, and sensitive genetic diagnostic screening of target pathogens and disease biomarkers. A primary limitation involves a simultaneous, sequence-specific identification of low copy number target polynucleotides using a clinically appropriate detection methodology that implements only inexpensive detection instrumentation. Here, a rapid (20 min), nonenzymatic method of signal amplification utilizing surface-initiated photopolymerization is presented in glass microarray format. Visible light photoinitiators covalently coupled to streptavidin were used to bind biotin-labeled capture sequences. Amplification was achieved through subsequent contact with a monomer solution and the appropriate light exposure to generate 20-240-nm-thick hydrogel layers exclusively from spots containing the biotin-labeled DNA. An amplification factor of 10(6) to 10(7) was observed as well as a detectable response generated from as low as approximately 10(4) labeled oligonucleotides using minimal instrumentation, such as an optical microscope or CCD camera.
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Affiliation(s)
- Ryan R Hansen
- Department of Chemical and Biological Engineering, ECCH 111 CB 424, University of Colorado, Boulder, Colorado 80309, USA
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39
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Neff PA, Serr A, Wunderlich BK, Bausch AR. Label-Free Electrical Determination of Trypsin Activity by a Silicon-on-Insulator Based Thin Film Resistor. Chemphyschem 2007; 8:2133-7. [PMID: 17722222 DOI: 10.1002/cphc.200700279] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
A silicon-on-insulator (SOI) based thin film resistor is employed for the label-free determination of enzymatic activity. We demonstrate that enzymes, which cleave biological polyelectrolyte substrates, can be detected by the sensor. As an application, we consider the serine endopeptidase trypsin, which cleaves poly-L-lysine (PLL). We show that PLL adsorbs quasi-irreversibly to the sensor and is digested by trypsin directly at the sensor surface. The created PLL fragments are released into the bulk solution due to kinetic reasons. This results in a measurable change of the surface potential allowing for the determination of trypsin concentrations down to 50 ng mL(-1). Chymotrypsin is a similar endopeptidase with a different specificity, which cleaves PLL with a lower efficiency as compared to trypsin. The activity of trypsin is analyzed quantitatively employing a kinetic model for enzyme-catalyzed surface reactions. Moreover, we have demonstrated the specific inactivation of trypsin by a serine protease inhibitor, which covalently binds to the active site of the enzyme.
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Affiliation(s)
- Petra A Neff
- Lehrstuhl für Biophysik-E22, Technische Universität München, Germany
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Wang Z, Wilkop T, Xu D, Dong Y, Ma G, Cheng Q. Surface plasmon resonance imaging for affinity analysis of aptamer-protein interactions with PDMS microfluidic chips. Anal Bioanal Chem 2007; 389:819-25. [PMID: 17673982 DOI: 10.1007/s00216-007-1510-x] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2007] [Revised: 07/02/2007] [Accepted: 07/12/2007] [Indexed: 01/03/2023]
Abstract
We report on the use of PDMS multichannels for affinity studies of DNA aptamer-human Immunoglobulin E (IgE) interactions by surface plasmon resonance imaging (SPRi). The sensing surface was prepared with thiol-terminated aptamers through a self-assembling process in the PDMS channels defined on a gold substrate. Cysteamine was codeposited with the thiol aptamers to promote proper spatial arrangement of the aptamers and thus maintain their optimal binding efficiencies. Four aptamers with different nucleic acid sequences were studied to test their interaction affinity toward IgE, and the results confirmed that aptamer I (5'-SH-GGG GCA CGT TTA TCC GTC CCT CCT AGT GGC GTG CCC C-3') has the strongest binding affinity. Control experiments were conducted with a PEG-functionalized surface and IgG was used to replace IgE in order to verify the selective binding of aptamer I to the IgE molecules. A linear concentration-dependent relationship between IgE and aptamer I was obtained, and a 2-nM detection limit was achieved. SPRi data were further analyzed by global fitting, and the dissociation constant of aptamer I-IgE complex was found to be 2.7 x 10(-7) M, which agrees relatively well with the values reported in the literature. Aptamer affinity screening by SPR imaging demonstrates marked advantages over competing methods because it does not require labeling, can be used in real-time, and is potentially high-throughput. The ability to provide both qualitative and quantitative results on a multichannel chip further establishes SPRi as a powerful tool for the study of biological interactions in a multiplexed format.
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Affiliation(s)
- Zhuangzhi Wang
- Department of Chemistry, University of California, Riverside, CA 92521, USA
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Luckarift HR, Balasubramanian S, Paliwal S, Johnson GR, Simonian AL. Enzyme-encapsulated silica monolayers for rapid functionalization of a gold surface. Colloids Surf B Biointerfaces 2007; 58:28-33. [PMID: 16996252 DOI: 10.1016/j.colsurfb.2006.08.013] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2006] [Accepted: 08/03/2006] [Indexed: 10/24/2022]
Abstract
We report a simple and rapid method for the deposition of amorphous silica onto a gold surface. The method is based on the ability of lysozyme to mediate the formation of silica nanoparticles. A monolayer of lysozyme is deposited via non-specific binding to gold. The lysozyme then mediates the self-assembled formation of a silica monolayer. The silica formation described herein occurs on a surface plasmon resonance (SPR) gold surface and is characterized by SPR spectroscopy. The silica layer significantly increases the surface area compared to the gold substrate and is directly compatible with a detection system. The maximum surface concentration of lysozyme was found to be a monolayer of 2.6 ng/mm(2) which allowed the deposition of a silica layer of a further 2 ng/mm(2). For additional surface functionalization, the silica was also demonstrated to be a suitable matrix for immobilization of biomolecules. The encapsulation of organophosphate hydrolase (OPH) was demonstrated as a model system. The silica forms at ambient conditions in a reaction that allows the encapsulation of enzymes directly during silica formation. OPH was successfully encapsulated within the silica particles and a detection limit for the substrate, paraoxon, using the surface-encapsulated enzyme was found to be 20 microM.
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Affiliation(s)
- Heather R Luckarift
- Air Force Research Laboratory, 139 Barnes Drive, Suite # 2, Tyndall AFB, FL 32403, USA
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Abstract
Refractive index-sensitive resonant waveguide grating biosensors are used to assay the label-free enzymatic degradation of biomolecules. These assays provide a robust means of screening for functional lytic modulators. The biomolecular substrates in this study were covalently immobilized through amine groups. Using the Corning® Epic™ System, the digestion signatures for multiple protein substrates on the biosensors are measured. Label-free digestion profiles for these proteins were substrate specific. Similarly, the authors find that the label-free digestion is protease specific. Enzyme-substrate pairs were used to evaluate high- throughput biosensors as tools for screening functional modulators. The lytic inhibitor properties for several proteases and dextranase are determined. The authors find that the IC50 values for the protease inhibitors agree with the reported values for several known inhibitors. The Ź values, using biosensor-based functional lytic screens, were routinely greater than 0.5, making this label-free application feasible for high-throughput screening.
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Masson JF, Kim YC, Obando LA, Peng W, Booksh KS. Fiber-optic surface plasmon resonance sensors in the near-infrared spectral region. APPLIED SPECTROSCOPY 2006; 60:1241-6. [PMID: 17132440 DOI: 10.1366/000370206778999139] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
The sensitivity of fiber-optic surface plasmon resonance (SPR) sensors was improved by a factor of at least thirteen for aqueous solutions by modifying the tip geometry to allow interrogation of the surface plasmon (SP) band in the near-infrared (NIR) region. This was achieved by tuning the angle at the distal end of the SPR sensor to a dual taper of 71 degrees and 19 degrees . Using a low numerical aperture (NA) fiber-optic sensor, NA = 0.12, is necessary to obtain a functional SPR sensor working in the NIR region. Theoretical simulations using the Maxwell equations demonstrated that even higher enhancement is theoretically possible while maintaining a narrow spectral feature upon the excitation of the SP bands on gold surfaces. The manufacture of the SPR sensors yields good agreement between theoretical simulations and experimental observations. To investigate the properties of these fiber-optic SPR-NIR sensors, sucrose solutions ranging from 0 to 15 x 10(-3) in mole fraction were utilized. The increased sensitivity of the fiber-optic SPR sensors, when used to monitor biomarkers, would yield lower detection limits. The smaller sensing area, compared to planar or other fiber-optic SPR sensors, combined with an improvement of the sensitivity, would yield a dramatic reduction of the absolute amount detected by biosensors.
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Affiliation(s)
- Jean-Francois Masson
- Department of Chemistry and Biochemistry, Arizona State University, Tempe, Arizona 85287-1604, USA
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Díaz-Mochón JJ, Tourniaire G, Bradley M. Microarray platforms for enzymatic and cell-based assays. Chem Soc Rev 2006; 36:449-57. [PMID: 17325784 DOI: 10.1039/b511848b] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
This tutorial review introduces the uninitiated to the world of microarrays (or so-called chips) and covers a number of basic concepts such as substrates and surfaces, printing and analysis. It then moves on to look at some newer applications of microarray technology, which include enzyme analysis (notably kinases and proteases) as well as the growing enchantment with so-called cell-based microarrays that offer a unique approach to high-throughput cellular analysis. Finally, it looks forwards and highlights future possible trends and directions in the microarray arena.
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Affiliation(s)
- Juan J Díaz-Mochón
- School of Chemistry, University of Edinburgh, Kings Buildings, West Mains Road, Edinburgh, EH9 3JJ, UK
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Scott BOS, Lavesa-Curto M, Bullard DR, Butt JN, Bowater RP. Immobilized DNA hairpins for assay of sequential breaking and joining of DNA backbones. Anal Biochem 2006; 358:90-8. [PMID: 16996469 DOI: 10.1016/j.ab.2006.08.010] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2006] [Revised: 07/21/2006] [Accepted: 08/05/2006] [Indexed: 10/24/2022]
Abstract
Immobilized DNA hairpins are exploited in a novel approach to assay DNA ligases and nucleases. A fundamental characteristic of the assay is that a fluorophore at the remote terminus of the hairpin reports on the integrity of the DNA backbone. The functionality of the protocol is confirmed using ATP- and NAD+-dependent DNA ligases and the nicking enzyme N.BbvCIA. The assay format is amenable to high-throughput analysis and quantitation of enzyme activity, and it is shown to be in excellent agreement with the more laborious electrophoretic approaches that are widely used for such analyses. Significantly, the assay is used to demonstrate sequential breaking and rejoining of a specific nucleic acid. Thus, a simple platform for biochemically innovative studies of pathways in cellular nucleic acid metabolism is demonstrated.
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Affiliation(s)
- Benjamin O S Scott
- School of Chemical Sciences and Pharmacy, University of East Anglia, Norwich NR4 7TJ, UK
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Li Y, Wark AW, Lee HJ, Corn RM. Single-nucleotide polymorphism genotyping by nanoparticle-enhanced surface plasmon resonance imaging measurements of surface ligation reactions. Anal Chem 2006; 78:3158-64. [PMID: 16643008 PMCID: PMC2504468 DOI: 10.1021/ac0600151] [Citation(s) in RCA: 130] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
A sensitive method for the analysis of single nucleotide polymorphisms (SNPs) in genomic DNA that utilizes nanoparticle-enhanced surface plasmon resonance imaging (SPRI) measurements of surface enzymatic ligation reactions on DNA microarrays is demonstrated. SNP identification was achieved by using sequence-specific surface reactions of the enzyme Taq DNA ligase, and the presence of ligation products on the DNA microarray elements was detected using SPRI through the hybridization adsorption of complementary oligonucleotides attached to gold nanoparticles. The use of gold nanoparticles increases the sensitivity of the SPRI so that single bases in oligonucleotides can be successfully identified at a concentration of 1 pM. This sensitivity is amply sufficient for performing multiplexed SNP genotyping by using multiple PCR amplicons and should also allow for the direct detection and identification of SNP sequences from 1 pM unamplified genomic DNA samples with this array-based and label-free SPRI methodology. As a first example of SNP genotyping, three different human genomic DNA samples were screened for a possible point mutation in the BRCA1 gene that is associated with breast cancer.
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Affiliation(s)
- Yuan Li
- University of California-Irvine, Irvine, California 92697, USA
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Abstract
We identified 1113 articles (103 reviews, 1010 primary research articles) published in 2005 that describe experiments performed using commercially available optical biosensors. While this number of publications is impressive, we find that the quality of the biosensor work in these articles is often pretty poor. It is a little disappointing that there appears to be only a small set of researchers who know how to properly perform, analyze, and present biosensor data. To help focus the field, we spotlight work published by 10 research groups that exemplify the quality of data one should expect to see from a biosensor experiment. Also, in an effort to raise awareness of the common problems in the biosensor field, we provide side-by-side examples of good and bad data sets from the 2005 literature.
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Affiliation(s)
- Rebecca L Rich
- Center for Biomolecular Interaction Analysis, University of Utah, Salt Lake City, UT 84132, USA
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