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Puumala LS, Grist SM, Morales JM, Bickford JR, Chrostowski L, Shekhar S, Cheung KC. Biofunctionalization of Multiplexed Silicon Photonic Biosensors. BIOSENSORS 2022; 13:bios13010053. [PMID: 36671887 PMCID: PMC9855810 DOI: 10.3390/bios13010053] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Revised: 12/10/2022] [Accepted: 12/23/2022] [Indexed: 05/28/2023]
Abstract
Silicon photonic (SiP) sensors offer a promising platform for robust and low-cost decentralized diagnostics due to their high scalability, low limit of detection, and ability to integrate multiple sensors for multiplexed analyte detection. Their CMOS-compatible fabrication enables chip-scale miniaturization, high scalability, and low-cost mass production. Sensitive, specific detection with silicon photonic sensors is afforded through biofunctionalization of the sensor surface; consequently, this functionalization chemistry is inextricably linked to sensor performance. In this review, we first highlight the biofunctionalization needs for SiP biosensors, including sensitivity, specificity, cost, shelf-stability, and replicability and establish a set of performance criteria. We then benchmark biofunctionalization strategies for SiP biosensors against these criteria, organizing the review around three key aspects: bioreceptor selection, immobilization strategies, and patterning techniques. First, we evaluate bioreceptors, including antibodies, aptamers, nucleic acid probes, molecularly imprinted polymers, peptides, glycans, and lectins. We then compare adsorption, bioaffinity, and covalent chemistries for immobilizing bioreceptors on SiP surfaces. Finally, we compare biopatterning techniques for spatially controlling and multiplexing the biofunctionalization of SiP sensors, including microcontact printing, pin- and pipette-based spotting, microfluidic patterning in channels, inkjet printing, and microfluidic probes.
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Affiliation(s)
- Lauren S. Puumala
- School of Biomedical Engineering, University of British Columbia, 2222 Health Sciences Mall, Vancouver, BC V6T 1Z3, Canada
- Centre for Blood Research, University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC V6T 1Z3, Canada
| | - Samantha M. Grist
- School of Biomedical Engineering, University of British Columbia, 2222 Health Sciences Mall, Vancouver, BC V6T 1Z3, Canada
- Centre for Blood Research, University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC V6T 1Z3, Canada
- Dream Photonics Inc., Vancouver, BC V6T 0A7, Canada
| | - Jennifer M. Morales
- Army Research Laboratory, US Army Combat Capabilities Development Command, 2800 Powder Mill Rd., Adelphi, MD 20783, USA
| | - Justin R. Bickford
- Army Research Laboratory, US Army Combat Capabilities Development Command, 2800 Powder Mill Rd., Adelphi, MD 20783, USA
| | - Lukas Chrostowski
- Dream Photonics Inc., Vancouver, BC V6T 0A7, Canada
- Department of Electrical and Computer Engineering, University of British Columbia, 2332 Main Mall, Vancouver, BC V6T 1Z4, Canada
- Stewart Blusson Quantum Matter Institute, University of British Columbia, 2355 East Mall, Vancouver, BC V6T 1Z4, Canada
| | - Sudip Shekhar
- Dream Photonics Inc., Vancouver, BC V6T 0A7, Canada
- Department of Electrical and Computer Engineering, University of British Columbia, 2332 Main Mall, Vancouver, BC V6T 1Z4, Canada
| | - Karen C. Cheung
- School of Biomedical Engineering, University of British Columbia, 2222 Health Sciences Mall, Vancouver, BC V6T 1Z3, Canada
- Centre for Blood Research, University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC V6T 1Z3, Canada
- Department of Electrical and Computer Engineering, University of British Columbia, 2332 Main Mall, Vancouver, BC V6T 1Z4, Canada
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2
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Angelopoulou M, Makarona E, Salapatas A, Misiakos K, Synolaki E, Ioannidis A, Chatzipanagiotou S, Ritvos MA, Pasternack A, Ritvos O, Petrou PS, Kakabakos SE. Directly immersible silicon photonic probes: Application to rapid SARS-CoV-2 serological testing. Biosens Bioelectron 2022; 215:114570. [PMID: 35850040 PMCID: PMC9273522 DOI: 10.1016/j.bios.2022.114570] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Revised: 07/07/2022] [Accepted: 07/09/2022] [Indexed: 01/31/2023]
Abstract
Silicon photonic probes based on broad-band Mach-Zehnder interferometry are explored for the first time as directly immersible immunosensors alleviating the need for microfluidics and pumps. Each probe includes two U-shaped waveguides allowing light in- and out-coupling from the same chip side through a bifurcated fiber and a mechanical coupler. At the opposite chip side, two Mach-Zehnder interferometers (MZI) are located enabling real-time monitoring of binding reactions by immersion of this chip side into a sample. The sensing arm windows of the two MZIs have different length resulting in two distinct peaks in the Fourier domain, the phase shift of which can be monitored independently through Fast Fourier Transform of the output spectrum. The photonic probes analytical potential was demonstrated through detection of antibodies against SARS-CoV-2 in human serum samples. For this, one MZI was functionalized with the Receptor Binding Domain (RBD) of SARS-CoV-2 Spike 1 protein, and the other with bovine serum albumin to serve as reference. The biofunctionalized probes were immersed for 10 min in human serum sample and then for 5 min in goat anti-human IgG Fc specific antibody solution. Using a humanized rat antibody against SARS-CoV-2 RBD, a detection limit of 20 ng/mL was determined. Analysis of human serum samples indicated that the proposed sensor discriminated completely non-infected/non-vaccinated from vaccinated individuals, and the antibodies levels determined correlated well with those determined in the same samples by ELISA. These results demonstrated the potential of the proposed sensor to serve as an efficient tool for expeditious point-of-care testing.
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Affiliation(s)
- Michailia Angelopoulou
- Institute of Nuclear & Radiological Science & Technology, Energy & Safety, NCSR “Demokritos”, Aghia Paraskevi, 15341, Greece
| | - Eleni Makarona
- Institute of Nanoscience and Nanotechnology, NCSR “Demokritos”, Aghia Paraskevi, 15341, Greece
| | - Alexandros Salapatas
- Institute of Nanoscience and Nanotechnology, NCSR “Demokritos”, Aghia Paraskevi, 15341, Greece
| | - Konstantinos Misiakos
- Institute of Nanoscience and Nanotechnology, NCSR “Demokritos”, Aghia Paraskevi, 15341, Greece
| | - Evgenia Synolaki
- Centre for Clinical, Experimental Surgery and Translational Research, Biomedical Research Foundation Academy of Athens, Athens, 11527, Greece
| | - Anastasios Ioannidis
- Department of Nursing, Faculty of Health Sciences, University of Peloponnese, Tripoli, 22100, Greece
| | - Stylianos Chatzipanagiotou
- Department of Medical Biopathology and Clinical Microbiology, Aeginition Hospital, Medical School, National and Kapodistrian University of Athens, Athens, 11528, Greece
| | - Mikael A. Ritvos
- Department of Physiology, Faculty of Medicine, University of Helsinki, Helsinki, 00014, Finland,School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH Royal Institute of Technology, Stockholm, Sweden,Nordic SARS Response AB, Stockholm, 19455, Sweden
| | - Arja Pasternack
- Department of Physiology, Faculty of Medicine, University of Helsinki, Helsinki, 00014, Finland
| | - Olli Ritvos
- Department of Physiology, Faculty of Medicine, University of Helsinki, Helsinki, 00014, Finland
| | - Panagiota S. Petrou
- Institute of Nuclear & Radiological Science & Technology, Energy & Safety, NCSR “Demokritos”, Aghia Paraskevi, 15341, Greece,Corresponding author. Research Immunoassays/Immunosensors Lab. INRASTES NCSR “Demokritos”, 15341 Aghia Paraskevi, Greece
| | - Sotirios E. Kakabakos
- Institute of Nuclear & Radiological Science & Technology, Energy & Safety, NCSR “Demokritos”, Aghia Paraskevi, 15341, Greece
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Fabrication of Multiscale 1-Octadecene Monolayer Patterned Arrays Based on a Chemomechanical Method. Processes (Basel) 2022. [DOI: 10.3390/pr10061090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
A controlled and self-assembled micromachining system was built to fabricate a mico/nanoscale monolayer patterned array on a silicon surface using a diamond tip. The process was as follows: (1) we preprocessed a silicon wafer to obtain a hydrogen-terminated silicon surface; (2) we scratched three rectangular arrays of 10 μm × 3 μm with a spacing of 2 μm on the silicon surface with a diamond tip in 1-octadecene solution; the Si-H bonds were broken, and silicon free radicals were formed; (3) the 1-octadecene molecules were connected with silicon atoms based on Si-C covalent bonds, and the 1-octadecene nano monolayer was self-assembled on the patterned arrays of the silicon surface. Atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), and Sessile water contact angles were used to detect and characterize the self-assembled monolayers (SAMs). The XPS results showed that the Si2p peak and the O1s peak were significantly decreased after self-assembly; however, the C1s peak was successively significantly increased. Sessile water contact angles showed that the hydrophilicity was weakened after the formation of 1-octenecene SAMs on the silicon substrate. The nanofriction of the sample was measured with AFM. The change in nanofriction also demonstrated that the SAMs were formed in accordance with the patterned array. We demonstrated that, by using this method, self-assembled multiscale structures on silicon substrate can be formed quickly and conveniently.
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Ettabib MA, Marti A, Liu Z, Bowden BM, Zervas MN, Bartlett PN, Wilkinson JS. Waveguide Enhanced Raman Spectroscopy for Biosensing: A Review. ACS Sens 2021; 6:2025-2045. [PMID: 34114813 DOI: 10.1021/acssensors.1c00366] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Waveguide enhanced Raman spectroscopy (WERS) utilizes simple, robust, high-index contrast dielectric waveguides to generate a strong evanescent field, through which laser light interacts with analytes residing on the surface of the waveguide. It offers a powerful tool for the direct identification and reproducible quantification of biochemical species and an alternative to surface enhanced Raman spectroscopy (SERS) without reliance on fragile noble metal nanostructures. The advent of low-cost laser diodes, compact spectrometers, and recent progress in material engineering, nanofabrication techniques, and software modeling tools have made realizing portable and cheap WERS Raman systems with high sensitivity a realistic possibility. This review highlights the latest progress in WERS technology and summarizes recent demonstrations and applications. Following an introduction to the fundamentals of WERS, the theoretical framework that underpins the WERS principles is presented. The main WERS design considerations are then discussed, and a review of the available approaches for the modification of waveguide surfaces for the attachment of different biorecognition elements is provided. The review concludes by discussing and contrasting the performance of recent WERS implementations, thereby providing a future roadmap of WERS technology where the key opportunities and challenges are highlighted.
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Affiliation(s)
- Mohamed A. Ettabib
- Zepler Institute for Photonics and Nanoelectronics, University of Southampton, Southampton SO17 1BJ, United Kingdom
| | - Almudena Marti
- School of Chemistry, University of Southampton, Southampton SO17 1BJ, United Kingdom
| | - Zhen Liu
- Zepler Institute for Photonics and Nanoelectronics, University of Southampton, Southampton SO17 1BJ, United Kingdom
| | - Bethany M. Bowden
- School of Chemistry, University of Southampton, Southampton SO17 1BJ, United Kingdom
| | - Michalis N. Zervas
- Zepler Institute for Photonics and Nanoelectronics, University of Southampton, Southampton SO17 1BJ, United Kingdom
| | - Philip N. Bartlett
- School of Chemistry, University of Southampton, Southampton SO17 1BJ, United Kingdom
| | - James S. Wilkinson
- Zepler Institute for Photonics and Nanoelectronics, University of Southampton, Southampton SO17 1BJ, United Kingdom
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Gasvoda RJ, Xu W, Zhang Z, Wang S, Hudson EA, Agarwal S. Selective Gas-Phase Functionalization of SiO 2 and SiN x Surfaces with Hydrocarbons. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2021; 37:3960-3969. [PMID: 33729812 DOI: 10.1021/acs.langmuir.1c00212] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Selective functionalization of dielectric surfaces is required for area-selective atomic layer deposition and etching. We have identified precursors for the selective gas-phase functionalization of plasma-deposited SiO2 and SiNx surfaces with hydrocarbons. The corresponding reaction mechanism of the precursor molecules with the two surfaces was studied using in situ surface infrared spectroscopy. We show that at a substrate temperature of 70 °C, cyclic azasilanes preferentially react with an -OH-terminated SiO2 surface over a -NHx-terminated SiNx surface with an attachment selectivity of ∼5.4, which is limited by the partial oxidation of the SiNx surface. The cyclic azasilane undergoes a ring-opening reaction where the Si-N bond cleaves upon the reaction with surface -OH groups forming a Si-O-Si linkage. After ring opening, the backbone of the grafted hydrocarbon is terminated with a secondary amine, -NHCH3, which can react with water to form an -OH-terminated surface and release CH3NH2 as the product. The surface coverage of the grafted cyclic azasilane is calculated as ∼3.3 × 1014 cm-2, assuming that each reacted -OH group contributes to one hydrocarbon linkage. For selective attachment to SiNx over SiO2 surfaces, we determined the reaction selectivity of aldehydes. We demonstrate that aldehydes selectively attach to SiNx over SiO2 surfaces, and for the specific branched aliphatic aldehyde used in this work, almost no reaction was detected with the SiO2 surface. A fraction of the aldehyde molecules reacts with surface -NH2 groups to form an imine (Si-N═C) surface linker with H2O released as the byproduct. The other fraction of the aldehydes also reacts with surface -NH2 groups but do not undergo the water-elimination step and remains attached to the surface as an aminoalcohol (Si-NH-COH-). The surface coverage of the grafted aldehyde is calculated as ∼9.8 × 1014 cm-2 using a known infrared absorbance cross-section for the -C(CH3)3 groups.
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Affiliation(s)
- Ryan J Gasvoda
- Chemical and Biological Engineering, Colorado School of Mines, Golden, Colorado 80401, United States
| | - Wanxing Xu
- Chemical and Biological Engineering, Colorado School of Mines, Golden, Colorado 80401, United States
| | - Zhonghao Zhang
- Lam Research Corporation, 4650 Cushing Parkway, Fremont, California 94538, United States
| | - Scott Wang
- Lam Research Corporation, 4650 Cushing Parkway, Fremont, California 94538, United States
| | - Eric A Hudson
- Lam Research Corporation, 4650 Cushing Parkway, Fremont, California 94538, United States
| | - Sumit Agarwal
- Chemical and Biological Engineering, Colorado School of Mines, Golden, Colorado 80401, United States
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Agarwal DK, Kushagra A, Ashwin M, Shukla AS, Palaparthy V. Sensitive detection of cardiac troponin-I protein using fabricated piezoresistive microcantilevers by a novel method of asymmetric biofunctionalization. NANOTECHNOLOGY 2020; 31:115503. [PMID: 31751958 DOI: 10.1088/1361-6528/ab5a18] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Microcantilever-based sensor platform has attracted a lot of attention over the time in detection of a variety of molecules due to their miniaturized dimensions. Sensitivity enhancement is an important aspect of such sensors, especially when used for point-of-care diagnostic purpose. However, the major concern while operating these sensors in deflection mode is their sensitivity which mainly relies on selective chemical modification protocols employed on these sensor surfaces. One of the ways of getting better sensitivity is through asymmetric (one side) biofunctionalization of the sensor surface. In the presented work here, we have demonstrated a novel approach of asymmetric biofunctionalization of proteins in overall sensitivity enhancement of piezoresistive silicon nitride-oxide microcantilever sensor platform inside a flow chamber. Herein, using our developed surface chemistry, asymmetrically biofunctionalized microcantilevers first exhibited a greater electrical response in terms of piezoresistance change than their symmetric counterpart in the detection of human immunoglobulins (HIgGs) protein. Finally, these microcantilevers were employed to exhibit the enhanced sensitivity towards the detection of a crucial cardiac marker protein, i.e. Troponin-I (cTnI) down to 250 ng ml-1 using asymmetric biofunctionalization process. This study shows that the developed asymmetric biofunctionalization methodology may be used as a general protocol to detect other important biomarkers of clinical applications with improved sensitivity.
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Affiliation(s)
- Dilip Kumar Agarwal
- Centre for Research in Nanotechnology and Science, Indian Institute of Technology Bombay, Mumbai, India. Centre of Excellence in Nanoelectronics, Dept. of Electrical Engineering, Indian Institute of Technology Bombay, Mumbai, India
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7
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Sato RH, Kosaka PM, Omori ÁT, Ferreira EA, Petri DFS, Malvar Ó, Domínguez CM, Pini V, Ahumada Ó, Tamayo J, Calleja M, Cunha RLOR, Fiorito PA. Development of a methodology for reversible chemical modification of silicon surfaces with application in nanomechanical biosensors. Biosens Bioelectron 2019; 137:287-293. [PMID: 31125818 DOI: 10.1016/j.bios.2019.04.028] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2019] [Revised: 04/09/2019] [Accepted: 04/14/2019] [Indexed: 10/26/2022]
Abstract
Hypervalent tellurium compounds have a particular reactivity towards thiol compounds which are related to their biological properties. In this work, this property was assembled to tellurium-functionalized surfaces. These compounds were used as linkers in the immobilization process of thiolated biomolecules (such as DNA) on microcantilever surfaces. The telluride derivatives acted as reversible binding agents due to their redox properties, providing the regeneration of microcantilever surfaces and allowing their reuse for further biomolecules immobilizations, recycling the functional surface. Initially, we started from the synthesis of 4-((3-((4-methoxyphenyl) tellanyl) phenyl) amino)-4-oxobutanoic acid, a new compound, which was immobilized on a silicon surface. In nanomechanical systems, the detection involved a hybridization study of thiolated DNA sequences. Fluorescence microscopy technique was used to confirm the immobilization and removal of the telluride-DNA system and provided revealing results about the potentiality of applying redox properties to chalcogen derivatives at surfaces.
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Affiliation(s)
- Roseli H Sato
- CCNH, Centro de Ciências Naturais e Humanas, Universidade Federal do ABC, UFABC, Avenida dos Estados, 5001, 09210-580, Santo André, São Paulo, Brazil
| | - Priscila M Kosaka
- Instituto Micro y Nanotecnología (IMN-CNM), CSIC, Isaac Newton 8 (PTM), Tres Cantos, Madrid, Spain
| | - Álvaro T Omori
- CCNH, Centro de Ciências Naturais e Humanas, Universidade Federal do ABC, UFABC, Avenida dos Estados, 5001, 09210-580, Santo André, São Paulo, Brazil
| | - Edgard A Ferreira
- Escola de Engenharia, Universidade Presbiteriana Mackenzie, 01302-907, São Paulo, SP, Brazil
| | - Denise F S Petri
- Departamento de Química Fundamental, Instituto de Química, Universidade de São Paulo, P.O. Box 26077, São Paulo, SP, 05513-970, Brazil
| | - Óscar Malvar
- Instituto Micro y Nanotecnología (IMN-CNM), CSIC, Isaac Newton 8 (PTM), Tres Cantos, Madrid, Spain
| | - Carmen M Domínguez
- Instituto Micro y Nanotecnología (IMN-CNM), CSIC, Isaac Newton 8 (PTM), Tres Cantos, Madrid, Spain
| | - Valerio Pini
- Instituto Micro y Nanotecnología (IMN-CNM), CSIC, Isaac Newton 8 (PTM), Tres Cantos, Madrid, Spain
| | - Óscar Ahumada
- Mecwins S.A, Plaza de la Encina 10-11, Núcleo 5, 2 B, 28760, Tres Cantos, Madrid, Spain
| | - Javier Tamayo
- Instituto Micro y Nanotecnología (IMN-CNM), CSIC, Isaac Newton 8 (PTM), Tres Cantos, Madrid, Spain
| | - Montserrat Calleja
- Instituto Micro y Nanotecnología (IMN-CNM), CSIC, Isaac Newton 8 (PTM), Tres Cantos, Madrid, Spain
| | - Rodrigo L O R Cunha
- CCNH, Centro de Ciências Naturais e Humanas, Universidade Federal do ABC, UFABC, Avenida dos Estados, 5001, 09210-580, Santo André, São Paulo, Brazil
| | - Pablo A Fiorito
- Centro de Investigaciones y Transferencia Villa María (CIT VM - CONICET), Instituto de Ciencias Básicas y Aplicadas, Universidad Nacional de Villa María, Av. Arturo Jauretche 1555, Villa María, C.P, 5900, Córdoba, Argentina.
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Ruiz-Tórtola Á, Prats-Quílez F, González-Lucas D, Bañuls MJ, Maquieira Á, Wheeler G, Dalmay T, Griol A, Hurtado J, Bohlmann H, Götzen R, García-Rupérez J. Experimental study of the evanescent-wave photonic sensors response in presence of molecular beacon conformational changes. JOURNAL OF BIOPHOTONICS 2018; 11:e201800030. [PMID: 29664230 DOI: 10.1002/jbio.201800030] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2018] [Accepted: 04/12/2018] [Indexed: 05/20/2023]
Abstract
An experimental study of the influence of the conformational change suffered by molecular beacon (MB) probes-upon the biorecognition of nucleic acid target oligonucleotides over evanescent wave photonic sensors-is reported. To this end, high sensitivity photonic sensors based on silicon photonic bandgap (PBG) structures were used, where the MB probes were immobilized via their 5' termination. Those MBs incorporate a biotin moiety close to their 3' termination in order to selectively bind a streptavidin molecule to them. The different photonic sensing responses obtained toward the target oligonucleotide detection, when the streptavidin molecule was bound to the MB probes or not, demonstrate the conformational change suffered by the MB upon hybridization, which promotes the displacement of the streptavidin molecule away from the surface of the photonic sensing structure.
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Affiliation(s)
- Ángela Ruiz-Tórtola
- Nanophotonics Technology Center, Universitat Politècnica de València, Valencia, Spain
| | | | - Daniel González-Lucas
- Departamento de Química, IDM, Instituto Interuniversitario de Investigación de Reconocimiento Molecular y Desarrollo Tecnológico, Universitat Politècnica de València, Valencia, Spain
| | - María-José Bañuls
- Departamento de Química, IDM, Instituto Interuniversitario de Investigación de Reconocimiento Molecular y Desarrollo Tecnológico, Universitat Politècnica de València, Valencia, Spain
| | - Ángel Maquieira
- Departamento de Química, IDM, Instituto Interuniversitario de Investigación de Reconocimiento Molecular y Desarrollo Tecnológico, Universitat Politècnica de València, Valencia, Spain
| | - Guy Wheeler
- School of Biological Sciences, University of East Anglia, Norwich, UK
| | - Tamas Dalmay
- School of Biological Sciences, University of East Anglia, Norwich, UK
| | - Amadeu Griol
- Nanophotonics Technology Center, Universitat Politècnica de València, Valencia, Spain
| | - Juan Hurtado
- Nanophotonics Technology Center, Universitat Politècnica de València, Valencia, Spain
| | - Helge Bohlmann
- microTEC Gesellschaft für Mikrotechnologie mbH, Duisburg, Germany
| | - Reiner Götzen
- microTEC Gesellschaft für Mikrotechnologie mbH, Duisburg, Germany
| | - Jaime García-Rupérez
- Nanophotonics Technology Center, Universitat Politècnica de València, Valencia, Spain
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9
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Biofunctionalized silicon nitride platform for sensing applications. Biosens Bioelectron 2018; 102:497-503. [DOI: 10.1016/j.bios.2017.11.059] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2017] [Revised: 11/15/2017] [Accepted: 11/22/2017] [Indexed: 11/20/2022]
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10
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González-Lucas D, Bañuls MJ, García-Rupérez J, Maquieira Á. Covalent attachment of biotinylated molecular beacons via thiol-ene coupling. A study on conformational changes upon hybridization and streptavidin binding. Mikrochim Acta 2017. [DOI: 10.1007/s00604-017-2310-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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11
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Emerging Cytokine Biosensors with Optical Detection Modalities and Nanomaterial-Enabled Signal Enhancement. SENSORS 2017; 17:s17020428. [PMID: 28241443 PMCID: PMC5335944 DOI: 10.3390/s17020428] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/13/2017] [Revised: 02/12/2017] [Accepted: 02/18/2017] [Indexed: 12/17/2022]
Abstract
Protein biomarkers, especially cytokines, play a pivotal role in the diagnosis and treatment of a wide spectrum of diseases. Therefore, a critical need for advanced cytokine sensors has been rapidly growing and will continue to expand to promote clinical testing, new biomarker development, and disease studies. In particular, sensors employing transduction principles of various optical modalities have emerged as the most common means of detection. In typical cytokine assays which are based on the binding affinities between the analytes of cytokines and their specific antibodies, optical schemes represent the most widely used mechanisms, with some serving as the gold standard against which all existing and new sensors are benchmarked. With recent advancements in nanoscience and nanotechnology, many of the recently emerging technologies for cytokine detection exploit various forms of nanomaterials for improved sensing capabilities. Nanomaterials have been demonstrated to exhibit exceptional optical properties unique to their reduced dimensionality. Novel sensing approaches based on the newly identified properties of nanomaterials have shown drastically improved performances in both the qualitative and quantitative analyses of cytokines. This article brings together the fundamentals in the literature that are central to different optical modalities developed for cytokine detection. Recent advancements in the applications of novel technologies are also discussed in terms of those that enable highly sensitive and multiplexed cytokine quantification spanning a wide dynamic range. For each highlighted optical technique, its current detection capabilities as well as associated challenges are discussed. Lastly, an outlook for nanomaterial-based cytokine sensors is provided from the perspective of optimizing the technologies for sensitivity and multiplexity as well as promoting widespread adaptations of the emerging optical techniques by lowering high thresholds currently present in the new approaches.
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12
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Park C, Lee J, Kim Y, Kim J, Lee J, Park S. 3D-printed microfluidic magnetic preconcentrator for the detection of bacterial pathogen using an ATP luminometer and antibody-conjugated magnetic nanoparticles. J Microbiol Methods 2016; 132:128-133. [PMID: 27923650 DOI: 10.1016/j.mimet.2016.12.001] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2016] [Revised: 11/30/2016] [Accepted: 12/01/2016] [Indexed: 11/16/2022]
Abstract
Various types of microfluidic systems have been developed to detect bacterial pathogens. However, most of these require enrichment steps that take at least several hours when detecting bacteria that are present with a low number of cells and, in addition, fabrication requires complicated assembly steps. In this study, we report the development of 3D microfluidic magnetic preconcentrator (3DμFMP) made of plastic via 3D printing without the need for any assembly. 3DμFMP could selectively preconcentrate enterohemorrhagic Escherichia coli O157:H7 in 100mL by a factor of 700 within 1h using antibody-conjugated magnetic nanoparticles (Ab-MNPs). With the combined use of an ATP luminometer, as low as 10 E. coli O157:H7 CFU (colony forming unit)/mL could be detected in blood. These results demonstrate the feasibility of 3DμFMP as a preconcentrator to improve the detection limit of existing bacterial detection systems.
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Affiliation(s)
- Chanyong Park
- Department of Biomedical Engineering, Sungkyunkwan University, Suwon, 16419, Republic of Korea
| | - Jinyeop Lee
- Department of Biomedical Engineering, Sungkyunkwan University, Suwon, 16419, Republic of Korea
| | - Yonghee Kim
- School of Mechanical Engineering, Sungkyunkwan University, Suwon, 16419, Republic of Korea
| | - Jaewon Kim
- School of Mechanical Engineering, Sungkyunkwan University, Suwon, 16419, Republic of Korea
| | - Jinkee Lee
- School of Mechanical Engineering, Sungkyunkwan University, Suwon, 16419, Republic of Korea
| | - Sungsu Park
- School of Mechanical Engineering, Sungkyunkwan University, Suwon, 16419, Republic of Korea.
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13
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Liu LH, Michalak DJ, Chopra TP, Pujari SP, Cabrera W, Dick D, Veyan JF, Hourani R, Halls MD, Zuilhof H, Chabal YJ. Surface etching, chemical modification and characterization of silicon nitride and silicon oxide--selective functionalization of Si3N4 and SiO2. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2016; 28:094014. [PMID: 26870908 DOI: 10.1088/0953-8984/28/9/094014] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The ability to selectively chemically functionalize silicon nitride (Si3N4) or silicon dioxide (SiO2) surfaces after cleaning would open interesting technological applications. In order to achieve this goal, the chemical composition of surfaces needs to be carefully characterized so that target chemical reactions can proceed on only one surface at a time. While wet-chemically cleaned silicon dioxide surfaces have been shown to be terminated with surficial Si-OH sites, chemical composition of the HF-etched silicon nitride surfaces is more controversial. In this work, we removed the native oxide under various aqueous HF-etching conditions and studied the chemical nature of the resulting Si3N4 surfaces using infrared absorption spectroscopy (IRAS), x-ray photoelectron spectroscopy (XPS), low energy ion scattering (LEIS), and contact angle measurements. We find that HF-etched silicon nitride surfaces are terminated by surficial Si-F and Si-OH bonds, with slightly subsurface Si-OH, Si-O-Si, and Si-NH2 groups. The concentration of surficial Si-F sites is not dependent on HF concentration, but the distribution of oxygen and Si-NH2 displays a weak dependence. The Si-OH groups of the etched nitride surface are shown to react in a similar manner to the Si-OH sites on SiO2, and therefore no selectivity was found. Chemical selectivity was, however, demonstrated by first reacting the -NH2 groups on the etched nitride surface with aldehyde molecules, which do not react with the Si-OH sites on a SiO2 surface, and then using trichloro-organosilanes for selective reaction only on the SiO2 surface (no reactivity on the aldehyde-terminated Si3N4 surface).
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Affiliation(s)
- Li-Hong Liu
- Department of Materials Science and Engineering, University of Texas at Dallas, Richardson, TX 75080, USA
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14
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Agarwal DK, Maheshwari N, Mukherji S, Rao VR. Asymmetric immobilization of antibodies on a piezo-resistive micro-cantilever surface. RSC Adv 2016. [DOI: 10.1039/c6ra01440b] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
For cantilever-based MEMS sensors, selective chemical modification of the sensing surface is used for the detection of chemical and biological analytes.
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Affiliation(s)
- Dilip Kumar Agarwal
- Centre of Excellence in Nanoelectronics
- Dept. of Electrical Engineering
- IIT Bombay
- Mumbai
- India
| | - Nidhi Maheshwari
- Centre of Excellence in Nanoelectronics
- Dept. of Electrical Engineering
- IIT Bombay
- Mumbai
- India
| | - Soumyo Mukherji
- Centre of Excellence in Nanoelectronics
- Dept. of Electrical Engineering
- IIT Bombay
- Mumbai
- India
| | - V. Ramgopal Rao
- Centre of Excellence in Nanoelectronics
- Dept. of Electrical Engineering
- IIT Bombay
- Mumbai
- India
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15
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Optimization of high-Q coupled nanobeam cavity for label-free sensing. SENSORS 2015; 15:25868-81. [PMID: 26473870 PMCID: PMC4634518 DOI: 10.3390/s151025868] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/18/2015] [Revised: 09/29/2015] [Accepted: 10/09/2015] [Indexed: 11/17/2022]
Abstract
We numerically and experimentally investigated the lateral coupling between photonic crystal (PhC) nanobeam (NB) cavities, pursuing high sensitivity and figure of merit (FOM) label-free biosensor. We numerically carried out 3D finite-difference time-domain (3D-FDTD) and the finite element method (FEM) simulations. We showed that when two PhC NB cavities separated by a small gap are evanescently coupled, the variation in the gap width significantly changes the coupling efficiency between the two coupled NB cavities and the resulting resonant frequencies split. Experimentally, we fabricated laterally-coupled PhC NB cavities using (InGaAsP) layer on the InP substrate. For sensing, we showed that the laterally coupled PhC NB cavities sensor exhibits higher sensitivity than the single PhC NB cavity. The higher sensitivity of laterally coupled PhC NB cavities is due to the strong evanescent coupling between nearby PhC NB cavities, which depends on the gap width and it is attributed to the large confinement of the electromagnetic field in the gap (air or liquid). As a result of the lateral coupling, both even (symmetric) and odd (asymmetric) modes exist. We show that even modes are more sensitive than odd modes. In addition, higher-order modes exhibit higher sensitivity. Hence, we characterized and examined the fabricated PhC NB cavity as a label-free biosensor, and it exhibits high figure of merit due to its high Q-factor. This illustrates a potentially useful method for optical sensing at nanoscale.
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16
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Optical biosensors with an integrated Mach-Zehnder Interferometer for detection of Listeria monocytogenes. Biomed Microdevices 2014; 16:509-20. [DOI: 10.1007/s10544-014-9853-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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17
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Description of an advantageous optical label-free biosensing interferometric read-out method to measure biological species. SENSORS 2014; 14:3675-89. [PMID: 24566633 PMCID: PMC3958242 DOI: 10.3390/s140203675] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/16/2013] [Revised: 01/23/2014] [Accepted: 02/19/2014] [Indexed: 12/03/2022]
Abstract
In this article we report a new, simple, and reliable optical read-out detection method able to assess Rotavirus present in human sera as well as in the viral pollution sources. It is based on the interference of two interferometers used as biophotonic transducers. The method significantly improves the optical label-free biosensing response measuring both, the concentration of the AgR and its corresponding size. Two different immunoassays were carried out: Bovine Serum Albumin (BSA), and the recognition by its antibody (anti-BSA); and Rotavirus (AgR) and the recognition by its antibody (anti-AgR). In the cases studied, and using as model interferometer a simple Fabry-Perot transducer, we demonstrate a biosensing enhancement of two orders of magnitude in the Limit of Detection (LoD). In fact, this read-out optical method may have significant implications to enhance other optical label-free photonic transducers reported in the scientific literature.
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18
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Slotted photonic crystal sensors. SENSORS 2013; 13:3675-710. [PMID: 23503295 PMCID: PMC3658769 DOI: 10.3390/s130303675] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/05/2013] [Revised: 02/27/2013] [Accepted: 03/08/2013] [Indexed: 12/24/2022]
Abstract
Optical biosensors are increasingly being considered for lab-on-a-chip applications due to their benefits such as small size, biocompatibility, passive behaviour and lack of the need for fluorescent labels. The light guiding mechanisms used by many of them results in poor overlap of the optical field with the target molecules, reducing the maximum sensitivity achievable. This review article presents a new platform for optical biosensors, namely slotted photonic crystals, which provide higher sensitivities due to their ability to confine, spatially and temporally, the optical mode peak within the analyte itself. Loss measurements showed values comparable to standard photonic crystals, confirming their ability to be used in real devices. A novel resonant coupler was designed, simulated, and experimentally tested, and was found to perform better than other solutions within the literature. Combining with cavities, microfluidics and biological functionalization allowed proof-of-principle demonstrations of protein binding to be carried out. Higher sensitivities were observed in smaller structures than possible with most competing devices reported in the literature. This body of work presents slotted photonic crystals as a realistic platform for complete on-chip biosensing; addressing key design, performance and application issues, whilst also opening up exciting new ideas for future study.
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19
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Bañuls MJ, Puchades R, Maquieira Á. Chemical surface modifications for the development of silicon-based label-free integrated optical (IO) biosensors: a review. Anal Chim Acta 2013; 777:1-16. [PMID: 23622959 DOI: 10.1016/j.aca.2013.01.025] [Citation(s) in RCA: 99] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2012] [Revised: 01/03/2013] [Accepted: 01/04/2013] [Indexed: 12/29/2022]
Abstract
Increasing interest has been paid to label-free biosensors in recent years. Among them, refractive index (RI) optical biosensors enable high density and the chip-scale integration of optical components. This makes them more appealing to help develop lab-on-a-chip devices. Today, many RI integrated optical (IO) devices are made using silicon-based materials. A key issue in their development is the biofunctionalization of sensing surfaces because they provide a specific, sensitive response to the analyte of interest. This review critically discusses the biofunctionalization procedures, assay formats and characterization techniques employed in setting up IO biosensors. In addition, it provides the most relevant results obtained from using these devices for real sample biosensing. Finally, an overview of the most promising future developments in the fields of chemical surface modification and capture agent attachment for IO biosensors follows.
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Affiliation(s)
- María-José Bañuls
- Centro de Reconocimiento Molecular y Desarrollo Tecnológico, Departamento de Química, Universitat Politècnica de València, Camino de Vera s/n, 46022 Valencia, Spain.
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20
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Peris E, Bañuls MJ, Puchades R, Maquieira Á. Photoattachment of thiolated DNA probes on SU-8 spin-coated Blu-ray disk surfaces for biosensing. J Mater Chem B 2013; 1:6245-6253. [DOI: 10.1039/c3tb21026j] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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21
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Manova RK, Pujari SP, Weijers CAGM, Zuilhof H, van Beek TA. Copper-free click biofunctionalization of silicon nitride surfaces via strain-promoted alkyne-azide cycloaddition reactions. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2012; 28:8651-63. [PMID: 22642374 DOI: 10.1021/la300921e] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Cu-free "click" chemistry is explored on silicon nitride (Si(3)N(4)) surfaces as an effective way for oriented immobilization of biomolecules. An ω-unsaturated ester was grafted onto Si(3)N(4) using UV irradiation. Hydrolysis followed by carbodiimide-mediated activation yielded surface-bound active succinimidyl and pentafluorophenyl ester groups. These reactive surfaces were employed for the attachment of bicyclononyne with an amine spacer, which subsequently enabled room temperature strain-promoted azide-alkyne cycloaddition (SPAAC). This stepwise approach was characterized by means of static water contact angle, X-ray photoelectron spectroscopy, and fluorescence microscopy. The surface-bound SPAAC reaction was studied with both a fluorine-tagged azide and an azide-linked lactose, yielding hydrophobic and bioactive surfaces for which the presence of trace amounts of Cu ions would have been problematic. Additionally, patterning of the Si(3)N(4) surface using this metal-free click reaction with a fluorescent azide is shown. These results demonstrate the ability of the SPAAC as a generic tool for anchoring complex molecules onto a surface under extremely mild, namely ambient and metal-free, conditions in a clean and relatively fast manner.
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Affiliation(s)
- Radostina K Manova
- Laboratory of Organic Chemistry, Wageningen University, Dreijenplein 8, 6703 HB Wageningen, The Netherlands
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22
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Grepstad JO, Kaspar P, Solgaard O, Johansen IR, Sudbø AS. Photonic-crystal membranes for optical detection of single nano-particles, designed for biosensor application. OPTICS EXPRESS 2012; 20:7954-7965. [PMID: 22453468 DOI: 10.1364/oe.20.007954] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
A sensor designed to detect bio-molecules is presented. The sensor exploits a planar 2D photonic crystal (PC) membrane with sub-micron thickness and through holes, to induce high optical fields that allow detection of nano-particles smaller than the diffraction limit of an optical microscope. We report on our design and fabrication of a PC membrane with a nano-particle trapped inside. We have also designed and built an imaging system where an optical microscope and a CCD camera are used to take images of the PC membrane. Results show how the trapped nano-particle appears as a bright spot in the image. In a first experimental realization of the imaging system, single particles with a radius of 75 nm can be detected.
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Affiliation(s)
- Jon Olav Grepstad
- Department of Electronics and Telecommunications, Norwegian University of Science and Technology, NO-7491 Trondheim, Norway.
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23
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Escorihuela J, Bañuls MJ, Puchades R, Maquieira Á. DNA microarrays on silicon surfaces through thiol-ene chemistry. Chem Commun (Camb) 2012; 48:2116-8. [DOI: 10.1039/c2cc17321b] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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24
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Liu Y, Xu XD, Chen JX, Cheng H, Zhang XZ, Zhuo RX. Surface self-assembly of N-fluorenyl-9-methoxycarbonyl diphenylalanine on silica wafer. Colloids Surf B Biointerfaces 2011; 87:192-7. [PMID: 21612897 DOI: 10.1016/j.colsurfb.2011.04.032] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2011] [Revised: 04/19/2011] [Accepted: 04/27/2011] [Indexed: 10/18/2022]
Abstract
N-Fluorenyl-9-methoxycarbonyl diphenylalanine (Fmoc-FF-OH) was chemically immobilized to the surface of silica wafer as the "seed". When immersing this peptide attached silica wafer into the dipeptide aqueous solution, the occurrence of a pH triggered surface self-assembly resulted in the formation of peptide nanorods on the surface of silica wafer. This surface self-assembly exhibited a dependence on the concentration of the dipeptide aqueous solution. It was proposed that the self-assembly of this dipeptide on the surface of silica wafer was similar to that in aqueous solution. In comparison with the conventional physical adsorption on the substrates, the chemically attached self-assembled nanorods exhibited much improved adsorption capacity on the substrate surface.
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Affiliation(s)
- Yun Liu
- Key Laboratory of Biomedical Polymers of Ministry of Education & Department of Chemistry, Wuhan University, Wuhan, PR China
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25
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Toccafondo V, García-Rupérez J, Bañuls MJ, Griol A, Castelló JG, Peransi-Llopis S, Maquieira A. Single-strand DNA detection using a planar photonic-crystal-waveguide-based sensor. OPTICS LETTERS 2010; 35:3673-3675. [PMID: 21042387 DOI: 10.1364/ol.35.003673] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
We report an experimental demonstration of single-strand DNA (ssDNA) detection at room temperature using a photonic-crystal-waveguide-based optical sensor. The sensor surface was previously biofunctionalized with ssDNA probes to be used as specific target receptors. Our experiments showed that it is possible to detect these hybridization events using planar photonic-crystal structures, reaching an estimated detection limit as low as 19.8 nM for the detection of the complementary DNA strand.
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Affiliation(s)
- V Toccafondo
- Nanophotonics Technology Center, Universidad Politécnica de Valencia, Camino de Vera s/n, 46022 Valencia, Spain.
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26
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Giorgis F, Descrovi E, Summonte C, Dominici L, Michelotti F. Experimental determination of the sensitivity of Bloch surface waves based sensors. OPTICS EXPRESS 2010; 18:8087-93. [PMID: 20588653 DOI: 10.1364/oe.18.008087] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Detection of glucose in water solution for several different concentrations has been performed with the purpose to determine the sensitivity of Near Infrared Bloch Surface Waves (lambda = 1.55microm) upon refractive index variations of the outer medium. TE-polarized electromagnetic surface waves are excited by a prism on a silicon nitride multilayer, according to the Kretschmann configuration. The real-time reflectance changes induced by discrete variations in glucose concentration has been revealed and analyzed. Without using any particular averaging strategy during the measurements, we pushed the device detection limit down to a glucose concentration of 2.5mg/dL, corresponding to a minimum detectable refractive index variation of the water solution as low as 3.8.10(-6).
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Affiliation(s)
- Fabrizio Giorgis
- Materials and Microsystems Laboratory - (lamda)Lab, Politecnico of Torino, C.so Duca degli Abruzzi 24, 10129 Torino, Italy.
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