1
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Julius L, Saeed MM, Kuijpers T, Sandu S, Henihan G, Dreo T, Schoen CD, Mishra R, Dunne NJ, Carthy E, Ducrée J, Kinahan DJ. Low-High-Low Rotationally Pulse-Actuated Serial Dissolvable Film Valves Applied to Solid Phase Extraction and LAMP Isothermal Amplification for Plant Pathogen Detection on a Lab-on-a-Disc. ACS OMEGA 2024; 9:3262-3275. [PMID: 38284094 PMCID: PMC10809376 DOI: 10.1021/acsomega.3c05117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/16/2023] [Revised: 12/13/2023] [Accepted: 12/14/2023] [Indexed: 01/30/2024]
Abstract
The ability of the centrifugal Lab-on-a-Disc (LoaD) platform to closely mimic the "on bench" liquid handling steps (laboratory unit operations (LUOs)) such as metering, mixing, and aliquoting supports on-disc automation of bioassay without the need for extensive biological optimization. Thus, well-established bioassays, normally conducted manually using pipettes or using liquid handling robots, can be relatively easily automated in self-contained microfluidic chips suitable for use in point-of-care or point-of-use settings. The LoaD's ease of automation is largely dependent on valves that can control liquid movement on the rotating disc. The optimum valving strategy for a true low-cost and portable device is rotationally actuated valves, which are actuated by changes in the disc spin-speed. However, due to tolerances in disc manufacturing and variations in reagent properties, most of these valving technologies have inherent variation in their actuation spin-speed. Most valves are actuated through stepped increases in disc spin-speed until the motor reaches its maximum speed (rarely more than 6000 rpm). These manufacturing tolerances combined with this "analogue" mechanism of valve actuation limits the number of LUOs that can be placed on-disc. In this work, we present a novel valving mechanism called low-high-low serial dissolvable film (DF) valves. In these valves, a DF membrane is placed in a dead-end pneumatic chamber. Below an actuation spin-speed, the trapped air prevents liquid wetting and dissolving the membrane. Above this spin-speed, the liquid will enter and wet the DF and open the valve. However, as DFs take ∼40 s to dissolve, the membrane can be wetted, and the disc spin-speed reduced before the film opens. Thus, by placing valves in a series, we can govern on which "digital pulse" in spin-speeding a reagent is released; a reservoir with one serial valve will open on the first pulse, a reservoir with two serial valves on the second, and so on. This "digital" flow control mechanism allows the automation of complex assays with high reliability. In this work, we first describe the operation of the valves, outline the theoretical basis for their operation, and support this analysis with an experiment. Next, we demonstrate how these valves can be used to automate the solid-phase extraction of DNA on on-disc LAMP amplification for applications in plant pathogen detection. The disc was successfully used to extract and detect, from a sample lysed off-disc, DNA indicating the presence of thermally inactivated Clavibacter michiganensis ssp. michiganensis (Cmm), a bacterial pathogen on tomato leaf samples.
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Affiliation(s)
- Lourdes
AN Julius
- Fraunhofer
Project Centre at Dublin City University, Dublin City University, Glasnevin D09 V209, Dublin, Ireland
- School
of Physical Sciences, Dublin City University, Dublin D09 V209, Ireland
- National
Centre for Sensor Research (NCSR), Dublin
City University, Dublin D09 V209, Ireland
| | - Muhammad Mubashar Saeed
- Biodesign
Europe, Dublin City University, Dublin D09 V209, Ireland
- School
of Mechanical and Manufacturing Engineering, Dublin City University, Glasnevin D09 V209, Dublin, Ireland
- SFI Centre
for Research Training in Machine Learning (ML-Laboratories), Dublin City University, Dublin D09 V209, Ireland
| | - Tim Kuijpers
- Biodesign
Europe, Dublin City University, Dublin D09 V209, Ireland
- School
of Mechanical and Manufacturing Engineering, Dublin City University, Glasnevin D09 V209, Dublin, Ireland
| | - Sergei Sandu
- Biodesign
Europe, Dublin City University, Dublin D09 V209, Ireland
- School
of Mechanical and Manufacturing Engineering, Dublin City University, Glasnevin D09 V209, Dublin, Ireland
| | - Grace Henihan
- Fraunhofer
Project Centre at Dublin City University, Dublin City University, Glasnevin D09 V209, Dublin, Ireland
- School
of Physical Sciences, Dublin City University, Dublin D09 V209, Ireland
- National
Centre for Sensor Research (NCSR), Dublin
City University, Dublin D09 V209, Ireland
| | - Tanja Dreo
- National
Institute of Biology, 1000 Ljubljana, Slovenia
| | - Cor D Schoen
- Wageningen
University and Research, 6708 PB Wageningen, The Netherlands
| | - Rohit Mishra
- Fraunhofer
Project Centre at Dublin City University, Dublin City University, Glasnevin D09 V209, Dublin, Ireland
- School
of Physical Sciences, Dublin City University, Dublin D09 V209, Ireland
- National
Centre for Sensor Research (NCSR), Dublin
City University, Dublin D09 V209, Ireland
| | - Nicholas J Dunne
- Biodesign
Europe, Dublin City University, Dublin D09 V209, Ireland
- School
of Mechanical and Manufacturing Engineering, Dublin City University, Glasnevin D09 V209, Dublin, Ireland
| | - Eadaoin Carthy
- National
Centre for Sensor Research (NCSR), Dublin
City University, Dublin D09 V209, Ireland
- Biodesign
Europe, Dublin City University, Dublin D09 V209, Ireland
- School
of Mechanical and Manufacturing Engineering, Dublin City University, Glasnevin D09 V209, Dublin, Ireland
| | - Jens Ducrée
- School
of Physical Sciences, Dublin City University, Dublin D09 V209, Ireland
- National
Centre for Sensor Research (NCSR), Dublin
City University, Dublin D09 V209, Ireland
- Biodesign
Europe, Dublin City University, Dublin D09 V209, Ireland
| | - David J Kinahan
- National
Centre for Sensor Research (NCSR), Dublin
City University, Dublin D09 V209, Ireland
- Biodesign
Europe, Dublin City University, Dublin D09 V209, Ireland
- School
of Mechanical and Manufacturing Engineering, Dublin City University, Glasnevin D09 V209, Dublin, Ireland
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2
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Early PL, Kilcawley NA, McArdle NA, Renou M, Kearney SM, Mishra R, Dimov N, Glynn MT, Ducrée J, Kinahan DJ. Digital process control of multi-step assays on centrifugal platforms using high-low-high rotational-pulse triggered valving. PLoS One 2023; 18:e0291165. [PMID: 37682949 PMCID: PMC10490917 DOI: 10.1371/journal.pone.0291165] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2023] [Accepted: 08/23/2023] [Indexed: 09/10/2023] Open
Abstract
Due to their capability for comprehensive sample-to-answer automation, the interest in centrifugal microfluidic systems has greatly increased in industry and academia over the last quarter century. The main applications of these "Lab-on-a-Disc" (LoaD) platforms are in decentralised bioanalytical point-of-use / point-of-care testing. Due to the unidirectional and omnipresent nature of the centrifugal force, advanced flow control is key to coordinate multi-step / multi-reagent assay formats on the LoaD. Formerly, flow control was often achieved by capillary burst valves which require gradual increments of the spin speed of the system-innate spindle motor. Recent advanced introduced a flow control scheme called 'rotational pulse actuated valves'. In these valves the sequence of valve actuation is determined by the architecture of the disc while actuation is triggered by freely programmable upward spike (i.e. Low-High-Low (LHL)) in the rotational frequency. This paradigm shift from conventional 'analogue' burst valves to 'digital' pulsing significantly increases the number of sequential while also improving the overall robustness of flow control. In this work, we expand on these LHL valves by introducing High-Low-High (HLH) pulse-actuated (PA) valving which are actuated by 'downward' spike in the disc spin-rate. These HLH valves are particularly useful for high spin-rate operations such as centrifugation of blood. We introduce two different HLH architectures and then combine the most promising with LHL valves to implement the time-dependent liquid handling protocol underlying a common liver function test panel.
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Affiliation(s)
- Philip L. Early
- School of Physical Sciences, Dublin City University, Glasnevin, Dublin, Ireland
- National Centre for Sensor Research, Dublin City University, Glasnevin, Dublin, Ireland
| | - Niamh A. Kilcawley
- School of Physical Sciences, Dublin City University, Glasnevin, Dublin, Ireland
- National Centre for Sensor Research, Dublin City University, Glasnevin, Dublin, Ireland
| | - Niamh A. McArdle
- School of Physical Sciences, Dublin City University, Glasnevin, Dublin, Ireland
- National Centre for Sensor Research, Dublin City University, Glasnevin, Dublin, Ireland
| | - Marine Renou
- School of Physical Sciences, Dublin City University, Glasnevin, Dublin, Ireland
- National Centre for Sensor Research, Dublin City University, Glasnevin, Dublin, Ireland
- Telecom Physique Strasbourg, Université de Strasbourg, Strasbourg, France
| | - Sinéad M. Kearney
- School of Physical Sciences, Dublin City University, Glasnevin, Dublin, Ireland
- National Centre for Sensor Research, Dublin City University, Glasnevin, Dublin, Ireland
| | - Rohit Mishra
- School of Physical Sciences, Dublin City University, Glasnevin, Dublin, Ireland
- National Centre for Sensor Research, Dublin City University, Glasnevin, Dublin, Ireland
| | - Nikolay Dimov
- School of Physical Sciences, Dublin City University, Glasnevin, Dublin, Ireland
- National Centre for Sensor Research, Dublin City University, Glasnevin, Dublin, Ireland
| | - Macdara T. Glynn
- School of Physical Sciences, Dublin City University, Glasnevin, Dublin, Ireland
- National Centre for Sensor Research, Dublin City University, Glasnevin, Dublin, Ireland
| | - Jens Ducrée
- School of Physical Sciences, Dublin City University, Glasnevin, Dublin, Ireland
- National Centre for Sensor Research, Dublin City University, Glasnevin, Dublin, Ireland
| | - David J. Kinahan
- School of Physical Sciences, Dublin City University, Glasnevin, Dublin, Ireland
- School of Mechanical and Manufacturing Engineering, Dublin City University, Glasnevin, Dublin, Ireland
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3
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Mishra R, Julius LA, Condon J, Pavelskopfa P, Early PL, Dorrian M, Mrvova K, Henihan G, Mangwanya F, Dreo T, Ducrée J, Macdonald NP, Schoen C, Kinahan DJ. Plant pathogen detection on a lab-on-a-disc using solid-phase extraction and isothermal nucleic acid amplification enabled by digital pulse-actuated dissolvable film valves. Anal Chim Acta 2023; 1258:341070. [PMID: 37087288 DOI: 10.1016/j.aca.2023.341070] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Revised: 03/06/2023] [Accepted: 03/07/2023] [Indexed: 03/21/2023]
Abstract
By virtue of its ruggedness, portability, rapid processing times, and ease-of-use, academic and commercial interest in centrifugal microfluidic systems has soared over the last decade. A key advantage of the LoaD platform is the ability to automate laboratory unit operations (LUOs) (mixing, metering, washing etc.) to support direct translation of 'on-bench' assays to 'on-chip'. Additionally, the LoaD requires just a low-cost spindle motor rather than specialized and expensive microfluidic pumps. Furthermore, when flow control (valves) is implemented through purely rotational changes in this same spindle motor (rather than using additional support instrumentation), the LoaD offers the potential to be a truly portable, low-cost and accessible platform. Current rotationally controlled valves are typically opened by sequentially increasing the disc spin-rate to a specific opening frequency. However, due lack of manufacturing fidelity these specific opening frequencies are better described as spin frequency 'bands'. With low-cost motors typically having a maximum spin-rate of 6000 rpm (100 Hz), using this 'analogue' approach places a limitation on the number of valves, which can be serially actuated thus limiting the number of LUOs that can be automated. In this work, a novel flow control scheme is presented where the sequence of valve actuation is determined by architecture of the disc while its timing is governed by freely programmable 'digital' pulses in its spin profile. This paradigm shift to 'digital' flow control enables automation of multi-step assays with high reliability, with full temporal control, and with the number of LUOs theoretically only limited by available space on the disc. We first describe the operational principle of these valves followed by a demonstration of the capability of these valves to automate complex assays by screening tomato leaf samples against plant pathogens. Reagents and lysed sample are loaded on-disc and then, in a fully autonomous fashion using only spindle-motor control, the complete assay is automated. Amplification and fluorescent acquisition take place on a custom spin-stand enabling the generation of real-time LAMP amplification curves using custom software. To prevent environmental contamination, the entire discs are sealed from atmosphere following loading with internal venting channels permitting easy movement of liquids about the disc. The disc was successfully used to detect the presence of thermally inactivated Clavibacter michiganensis. Michiganensis (CMM) bacterial pathogen on tomato leaf samples.
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Affiliation(s)
- Rohit Mishra
- Fraunhofer Project Centre at Dublin City University, Dublin City University, Glasnevin, Dublin, Ireland; School of Physical Sciences, Dublin City University, Dublin, Ireland; National Centre for Sensor Research (NCSR), Dublin City University, Dublin, Ireland; Biodesign Europe, Dublin City University, Dublin, Ireland.
| | - Lourdes An Julius
- Fraunhofer Project Centre at Dublin City University, Dublin City University, Glasnevin, Dublin, Ireland
| | - Jack Condon
- Fraunhofer Project Centre at Dublin City University, Dublin City University, Glasnevin, Dublin, Ireland
| | - Patricija Pavelskopfa
- Fraunhofer Project Centre at Dublin City University, Dublin City University, Glasnevin, Dublin, Ireland
| | - Philip L Early
- Fraunhofer Project Centre at Dublin City University, Dublin City University, Glasnevin, Dublin, Ireland; School of Physical Sciences, Dublin City University, Dublin, Ireland; School of Mechanical and Manufacturing Engineering, Dublin City University, Glasnevin, Dublin, Ireland
| | - Matthew Dorrian
- Fraunhofer Project Centre at Dublin City University, Dublin City University, Glasnevin, Dublin, Ireland
| | - Katarina Mrvova
- Fraunhofer Project Centre at Dublin City University, Dublin City University, Glasnevin, Dublin, Ireland
| | - Grace Henihan
- Fraunhofer Project Centre at Dublin City University, Dublin City University, Glasnevin, Dublin, Ireland
| | - Faith Mangwanya
- Fraunhofer Project Centre at Dublin City University, Dublin City University, Glasnevin, Dublin, Ireland
| | - Tanya Dreo
- National Institute of Biology, Ljubljana, Slovenia
| | - Jens Ducrée
- School of Physical Sciences, Dublin City University, Dublin, Ireland
| | - Niall P Macdonald
- Fraunhofer Project Centre at Dublin City University, Dublin City University, Glasnevin, Dublin, Ireland
| | - Cor Schoen
- Wageningen University Research, Wageningen, the Netherlands
| | - David J Kinahan
- Fraunhofer Project Centre at Dublin City University, Dublin City University, Glasnevin, Dublin, Ireland; National Centre for Sensor Research (NCSR), Dublin City University, Dublin, Ireland; Biodesign Europe, Dublin City University, Dublin, Ireland; School of Mechanical and Manufacturing Engineering, Dublin City University, Glasnevin, Dublin, Ireland.
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4
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Peshin S, Madou M, Kulinsky L. Microvalves for Applications in Centrifugal Microfluidics. SENSORS (BASEL, SWITZERLAND) 2022; 22:8955. [PMID: 36433550 PMCID: PMC9693484 DOI: 10.3390/s22228955] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Revised: 11/11/2022] [Accepted: 11/17/2022] [Indexed: 06/16/2023]
Abstract
Centrifugal microfluidic platforms (CDs) have opened new possibilities for inexpensive point-of-care (POC) diagnostics. They are now widely used in applications requiring polymerase chain reaction steps, blood plasma separation, serial dilutions, and many other diagnostic processes. CD microfluidic devices allow a variety of complex processes to transfer onto the small disc platform that previously were carried out by individual expensive laboratory equipment requiring trained personnel. The portability, ease of operation, integration, and robustness of the CD fluidic platforms requires simple, reliable, and scalable designs to control the flow of fluids. Valves play a vital role in opening/closing of microfluidic channels to enable a precise control of the flow of fluids on a centrifugal platform. Valving systems are also critical in isolating chambers from the rest of a fluidic network at required times, in effectively directing the reagents to the target location, in serial dilutions, and in integration of multiple other processes on a single CD. In this paper, we review the various available fluidic valving systems, discuss their working principles, and evaluate their compatibility with CD fluidic platforms. We categorize the presented valving systems into either "active", "passive", or "hybrid"-based on their actuation mechanism that can be mechanical, thermal, hydrophobic/hydrophilic, solubility-based, phase-change, and others. Important topics such as their actuation mechanism, governing physics, variability of performance, necessary disc spin rate for valve actuation, valve response time, and other parameters are discussed. The applicability of some types of valves for specialized functions such as reagent storage, flow control, and other applications is summarized.
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Affiliation(s)
- Snehan Peshin
- Department of Mechanical and Aerospace Engineering, University of California, Irvine, CA 92697, USA
| | - Marc Madou
- Department of Mechanical and Aerospace Engineering, University of California, Irvine, CA 92697, USA
- School of Engineering and Science, Tecnológico de Monterrey, Monterrey 64849, Mexico
| | - Lawrence Kulinsky
- Department of Mechanical and Aerospace Engineering, University of California, Irvine, CA 92697, USA
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5
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Regan B, Kinahan D, Daly P, O'Kennedy R, Collins D. Design and fabrication of a low-cost wireless camera imaging system for centrifugal microfluidics. HARDWAREX 2022; 11:e00259. [PMID: 35509901 PMCID: PMC9058586 DOI: 10.1016/j.ohx.2022.e00259] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Revised: 12/23/2021] [Accepted: 01/03/2022] [Indexed: 06/14/2023]
Abstract
Centrifugal microfluidic devices offer a robust method for low-volume fluid handling by combining low-cost instrumentation with highly integrated automation. Crucial to the efficacy of Lab-on-a-Disc (LoaD) device operation is the selection of robust valving technology, the design of on-disc fluidic structures, and accurate control of disc spin-speeds (centrifugal force) during operation. The design and refinement of fluidic and valving structures is often guided by inspecting disc operation using high-speed camera systems. This approach involves synchronising image acquisition with disc rotation to visualise liquid flow through a series of images often presented in a video format. Depending on the decisions taken, such systems can cost from €4,000 upwards. This paper outlines the development of a low-cost centrifugal test-stand with an integrated imaging system using a generic wireless camera to record videos directly to a smartphone device. This imaging system can be fabricated using only 3D printers and a low-cost CNC milling machine from widely available materials for approximately €350. High-fidelity imaging of the entire disc for flow visualisation and the recording of real-time colour intensity measurements are facilitated by this standalone device. A vibration analysis study has been performed to determine the rotational velocity range at which the system can be safely operated. Furthermore, the efficacy of the imaging system has been demonstrated by performing real-time colour intensity measurements of dyed water dilutions.
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Affiliation(s)
- Brian Regan
- School of Biotechnology, Dublin City University, Dublin 9, Ireland
| | - David Kinahan
- School of Mechanical Engineering, Dublin City University, Dublin 9, Ireland
| | - Philip Daly
- School of Mechanical Engineering, Dublin City University, Dublin 9, Ireland
| | - Richard O'Kennedy
- School of Biotechnology, Dublin City University, Dublin 9, Ireland
- Hamad Bin Khalifa University, Qatar Foundation, Doha, Qatar
| | - David Collins
- School of Biotechnology, Dublin City University, Dublin 9, Ireland
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6
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Ducrée J. Systematic review of centrifugal valving based on digital twin modeling towards highly integrated lab-on-a-disc systems. MICROSYSTEMS & NANOENGINEERING 2021; 7:104. [PMID: 34987859 PMCID: PMC8677742 DOI: 10.1038/s41378-021-00317-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Revised: 09/16/2021] [Accepted: 09/27/2021] [Indexed: 05/07/2023]
Abstract
Current, application-driven trends towards larger-scale integration (LSI) of microfluidic systems for comprehensive assay automation and multiplexing pose significant technological and economical challenges to developers. By virtue of their intrinsic capability for powerful sample preparation, centrifugal systems have attracted significant interest in academia and business since the early 1990s. This review models common, rotationally controlled valving schemes at the heart of such "Lab-on-a-Disc" (LoaD) platforms to predict critical spin rates and reliability of flow control which mainly depend on geometries, location and liquid volumes to be processed, and their experimental tolerances. In absence of larger-scale manufacturing facilities during product development, the method presented here facilitates efficient simulation tools for virtual prototyping and characterization and algorithmic design optimization according to key performance metrics. This virtual in silico approach thus significantly accelerates, de-risks and lowers costs along the critical advancement from idea, layout, fluidic testing, bioanalytical validation, and scale-up to commercial mass manufacture.
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Affiliation(s)
- Jens Ducrée
- School of Physical Sciences, Dublin City University, Dublin, Ireland
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7
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Uddin R, Kinahan D, Ducrée J, Boisen A. Lab-on-a-disk extraction of PBMC and metered plasma from whole blood: An advanced event-triggered valving strategy. BIOMICROFLUIDICS 2021; 15:064102. [PMID: 34804316 PMCID: PMC8580574 DOI: 10.1063/5.0066128] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2021] [Accepted: 10/10/2021] [Indexed: 06/13/2023]
Abstract
In this paper, we present a centrifugal microfluidic concept employing event-triggered valving for automated extraction of metered plasma and peripheral blood mononuclear cells (PBMCs). This "lab-on-a-disk" system has been developed for retrieving different density layers from a liquid column by "overflowing" the layers sequentially using the pressure exerted by a density-gradient liquid. Defined volumes of plasma and PBMCs were efficiently forwarded into designated microfluidic chambers as a sample preparation step prior to further downstream processing. Furthermore, the extracted PBMCs were counted directly on-disk using an automated optical unit by object-based image analysis, thus eliminating the requirement for the post-processing of the extracted PBMCs. This study is a direct continuation of our previous work1 where we demonstrated combined on-disk detection of C-reactive protein and quantification of PBMCs following on-disk extraction of plasma and PBMCs from a single blood sample using a centrifugo-pneumatic valving mechanism. However, the former valving technique featured limited PBMC extraction efficiency. Here, integrating the novel concept along with event-triggered valving mechanism, we eliminated the occurrence of a specific microfluidic effect, which led us to increase PBMC extraction efficiency to 88%. This extraction method has the potential to be utilized for efficiently separating multiple density layers from a liquid sample in relevant biomedical applications.
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Affiliation(s)
- Rokon Uddin
- Department of Health Technology, Technical University of Denmark, Kongens Lyngby, Denmark
| | - David Kinahan
- Department of Mechanical and Manufacturing Engineering, Dublin City University, Glasnevin, Dublin 9, Ireland
| | - Jens Ducrée
- FPC@DCU—Fraunhofer Project Center at Dublin City University, Glasnevin, Dublin 9, Ireland
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8
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Ducrée J. Secure Air Traffic Control at the Hub of Multiplexing on the Centrifugo-Pneumatic Lab-on-a-Disc Platform. MICROMACHINES 2021; 12:700. [PMID: 34203926 PMCID: PMC8232791 DOI: 10.3390/mi12060700] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Revised: 06/01/2021] [Accepted: 06/10/2021] [Indexed: 12/14/2022]
Abstract
Fluidic larger-scale integration (LSI) resides at the heart of comprehensive sample-to-answer automation and parallelization of assay panels for frequent and ubiquitous bioanalytical testing in decentralized point-of-use/point-of-care settings. This paper develops a novel "digital twin" strategy with an emphasis on rotational, centrifugo-pneumatic flow control. The underlying model systematically connects retention rates of rotationally actuated valves as a key element of LSI to experimental input parameters; for the first time, the concept of band widths in frequency space as the decisive quantity characterizing operational robustness is introduced, a set of quantitative performance metrics guiding algorithmic optimization of disc layouts is defined, and the engineering principles of advanced, logical flow control and timing are elucidated. Overall, the digital twin enables efficient design for automating multiplexed bioassay protocols on such "Lab-on-a-Disc" (LoaD) systems featuring high packing density, reliability, configurability, modularity, and manufacturability to eventually minimize cost, time, and risk of development and production.
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Affiliation(s)
- Jens Ducrée
- School of Physical Sciences, Dublin City University, Glasnevin, Dublin 9, Ireland
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9
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Henderson BD, Kinahan DJ, Rio J, Mishra R, King D, Torres-Delgado SM, Mager D, Korvink JG, Ducrée J. Siphon-Controlled Automation on a Lab-on-a-Disc Using Event-Triggered Dissolvable Film Valves. BIOSENSORS-BASEL 2021; 11:bios11030073. [PMID: 33800811 PMCID: PMC8000095 DOI: 10.3390/bios11030073] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Revised: 02/24/2021] [Accepted: 03/02/2021] [Indexed: 12/14/2022]
Abstract
Within microfluidic technologies, the centrifugal microfluidic “Lab-on-a-Disc” (LoaD) platform offers great potential for use at the PoC and in low-resource settings due to its robustness and the ability to port and miniaturize ‘wet bench’ laboratory protocols. We present the combination of ‘event-triggered dissolvable film valves’ with a centrifugo-pneumatic siphon structure to enable control and timing, through changes in disc spin-speed, of the release and incubations of eight samples/reagents/wash buffers. Based on these microfluidic techniques, we integrated and automated a chemiluminescent immunoassay for detection of the CVD risk factor marker C-reactive protein displaying a limit of detection (LOD) of 44.87 ng mL−1 and limit of quantitation (LoQ) of 135.87 ng mL−1.
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Affiliation(s)
- Brian D. Henderson
- School of Physical Sciences, Dublin City University, Dublin 9, Ireland; (B.D.H.); (J.R.)
| | - David J. Kinahan
- School of Mechanical Engineering, Dublin City University, Dublin 9, Ireland;
- National Center for Sensor Research, Dublin City University, Dublin 9, Ireland
- I-Form, the SFI Research Centre for Advanced Manufacturing, Dublin City University, Dublin 9, Ireland
- The Water Institute, Dublin City University, Dublin 9, Ireland
| | - Jeanne Rio
- School of Physical Sciences, Dublin City University, Dublin 9, Ireland; (B.D.H.); (J.R.)
| | - Rohit Mishra
- Fraunhofer Project Center, Dublin City University, Dublin 9, Ireland; (R.M.); (D.K.)
| | - Damien King
- Fraunhofer Project Center, Dublin City University, Dublin 9, Ireland; (R.M.); (D.K.)
| | - Sarai M. Torres-Delgado
- Institute of Microstructure Technology, Karlsruhe Institute of Technology, 76344 Karlsruhe, Germany; (S.M.T.-D.); (D.M.); (J.G.K.)
| | - Dario Mager
- Institute of Microstructure Technology, Karlsruhe Institute of Technology, 76344 Karlsruhe, Germany; (S.M.T.-D.); (D.M.); (J.G.K.)
| | - Jan G. Korvink
- Institute of Microstructure Technology, Karlsruhe Institute of Technology, 76344 Karlsruhe, Germany; (S.M.T.-D.); (D.M.); (J.G.K.)
| | - Jens Ducrée
- School of Physical Sciences, Dublin City University, Dublin 9, Ireland; (B.D.H.); (J.R.)
- Correspondence: ; Tel.: +353-1-700-5377
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10
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Akuoko Y, Hanson RL, Harris DH, Nielsen JB, Lazalde E, Woolley AT. Rapid and simple pressure-sensitive adhesive microdevice fabrication for sequence-specific capture and fluorescence detection of sepsis-related bacterial plasmid gene sequences. Anal Bioanal Chem 2021; 413:1017-1025. [PMID: 33247338 PMCID: PMC7855688 DOI: 10.1007/s00216-020-03060-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Revised: 11/06/2020] [Accepted: 11/10/2020] [Indexed: 10/22/2022]
Abstract
Microbial resistance to currently available antibiotics poses a great threat in the global fight against infections. An important step in determining bacterial antibiotic resistance can be selective DNA sequence capture and fluorescence labeling. In this paper, we demonstrate the fabrication of simple, robust, inexpensive microfluidic devices for DNA capture and fluorescence detection of a model antibiotic resistance gene sequence. We laser micromachined polymethyl methacrylate microchannels and enclosed them using pressure-sensitive adhesive tapes. We then formed porous polymer monoliths with DNA capture probes in these microchannels and used them for sequence-specific capture, fluorescent labeling, and laser-induced fluorescence detection of picomolar (pM) concentrations of synthetic and plasmid antibiotic resistance gene targets. The relative fluorescence for the elution peaks increased with loaded target DNA concentration. We observed higher fluorescence signal and percent recovery for synthetic target DNA compared to plasmid DNA at the same loaded target concentration. A non-target gene was used for control experiments and produced < 3% capture relative to the same concentration of target. The full analysis process including device fabrication was completed in less than 90 min with a limit of detection of 30 pM. The simplicity of device fabrication and good DNA capture selectivity demonstrated herein have potential for application with processes for bacterial plasmid DNA extraction and single-particle counting to facilitate determination of antibiotic susceptibility. Graphical abstract.
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Affiliation(s)
- Yesman Akuoko
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, UT, 84602, USA
| | - Robert L Hanson
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, UT, 84602, USA
| | - David H Harris
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, UT, 84602, USA
| | - Jacob B Nielsen
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, UT, 84602, USA
| | - Elaine Lazalde
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, UT, 84602, USA
| | - Adam T Woolley
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, UT, 84602, USA.
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11
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Ducrée J, Gravitt M, Walshe R, Bartling S, Etzrodt M, Harrington T. Open Platform Concept for Blockchain-Enabled Crowdsourcing of Technology Development and Supply Chains. FRONTIERS IN BLOCKCHAIN 2020. [DOI: 10.3389/fbloc.2020.586525] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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12
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Abstract
Lab-on-a-Disc (LoaD) biosensors are increasingly a promising solution for many biosensing applications. In the search for a perfect match between point-of-care (PoC) microfluidic devices and biosensors, the LoaD platform has the potential to be reliable, sensitive, low-cost, and easy-to-use. The present global pandemic draws attention to the importance of rapid sample-to-answer PoC devices for minimising manual intervention and sample manipulation, thus increasing the safety of the health professional while minimising the chances of sample contamination. A biosensor is defined by its ability to measure an analyte by converting a biological binding event to tangible analytical data. With evolving manufacturing processes for both LoaDs and biosensors, it is becoming more feasible to embed biosensors within the platform and/or to pair the microfluidic cartridges with low-cost detection systems. This review considers the basics of the centrifugal microfluidics and describes recent developments in common biosensing methods and novel technologies for fluidic control and automation. Finally, an overview of current devices on the market is provided. This review will guide scientists who want to initiate research in LoaD PoC devices as well as providing valuable reference material to researchers active in the field.
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13
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Abstract
We present a powerful and compact batch-mode mixing and dilution technique for centrifugal microfluidic platforms. Siphon structures are designed to discretize continuous flows into a sequence of droplets of volumes as low as 100 nL. Using a passive, self-regulating 4-step mechanism, discrete volumes of two fluids are alternatingly issued into a common intermediate chamber. At its base, a capillary valve acts as a fluidic shift register; a single droplet is held in place while two or more droplets merge and pass through the capillary stop. These merged droplets are advectively mixed as they pass through the capillary valve and into the receiving chamber. Mixing is demonstrated for various combinations of liquids such as aqueous solutions as well as saline solutions and human plasma. The mixing quality is assessed on a quantitative scale by using a colorimetric method based on the mixing of potassium thiocyanate and iron(III) chloride, and in the case of human plasma using a spectroscopic method. For instance, volumes of 5 µL have been mixed in less than 20 s. Single-step dilutions up to 1:5 of plasma in a standard phosphate buffer solution are also demonstrated. This work describes the preliminary development of the mixing method which has since been integrated into a commercially available microfluidic cartridge.
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14
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Chen Y, Shen M, Zhu Y, Xu Y. A novel electromagnet-triggered pillar valve and its application in immunoassay on a centrifugal platform. LAB ON A CHIP 2019; 19:1728-1735. [PMID: 31020298 DOI: 10.1039/c9lc00043g] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The lab-on-a-disc is a powerful microfluidic platform that skillfully takes advantage of centrifugal force to controllably drive liquids with the assistance of passive or active valves. However, the passive valves are mainly triggered by the rotation speed and can be easily influenced by the surface chemistry of the channel, while the active valves usually require a complicated fabrication or actuation procedure. In this study, a novel active valve that can be easily triggered by an electromagnet was proposed and applied on the centrifugation platform. This valve, named the electromagnet-triggered pillar (ETP) valve, consisted of a metal pin and pressure sensitive adhesive (PSA) tape, and is closed until the pin is lifted up by an electromagnet to partially separate the PSA tape from the substrate. As a typical application, this valve is utilized to construct a centrifugal chip for mycotoxin detection. With four ETP valves in a unit, the sample and liquid reagents can be sequentially released into the reaction chamber that was spotted with mycotoxin conjugates to accomplish the whole immunoassay. Four mycotoxins (aflatoxin B1, ochratoxin A, T-2 toxin, and zearalenone) were simultaneously detected on this chip with limits of detection lower than the permissible limits set by the regulatory agencies of China, demonstrating the practicability of this easy-to-use active valve.
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Affiliation(s)
- Yiqi Chen
- Department of Biomedical Engineering, Tsinghua University School of Medicine, Beijing 100084, China.
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15
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Torres Delgado SM, Korvink JG, Mager D. The eLoaD platform endows centrifugal microfluidics with on-disc power and communication. Biosens Bioelectron 2018; 117:464-473. [DOI: 10.1016/j.bios.2018.05.056] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2018] [Revised: 05/24/2018] [Accepted: 05/29/2018] [Indexed: 01/18/2023]
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16
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Miyazaki CM, Kinahan DJ, Mishra R, Mangwanya F, Kilcawley N, Ferreira M, Ducrée J. Label-free, spatially multiplexed SPR detection of immunoassays on a highly integrated centrifugal Lab-on-a-Disc platform. Biosens Bioelectron 2018; 119:86-93. [PMID: 30103158 DOI: 10.1016/j.bios.2018.07.056] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2018] [Revised: 07/18/2018] [Accepted: 07/27/2018] [Indexed: 02/06/2023]
Abstract
As a direct, label-free method, Surface Plasmon Resonance (SPR) detection significantly reduces the needs for liquid handling and reagent storage compared to common enzyme-linked immunosorbent assays (ELISAs), thus enabling comprehensive multiplexing of bioassays on microfluidic sample-to-answer systems. This paper describes a highly integrated centrifugal Lab-on-a-Disc (LoaD) platform for automating the full process chain extending between plasma extraction and subsequent aliquoting to five parallelized reaction channels for quantitative SPR detection by an inexpensive smartphone camera. The entire, multi-step / multi-reagent operation completes within less than 1 h. While the emphasis of this work is on the fluidic automation and parallelization by previously introduced, very robust event-triggered valving and buoyancy-driven centripetal pumping schemes, we successfully implement an immunoglobulin G (IgG) assay; by specific functionalization of the detection surfaces, the same disc layout can readily be customised for immunoassays panels from whole blood.
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Affiliation(s)
- Celina M Miyazaki
- FPC@DCU - Fraunhofer Project Centre for Embedded Bioanalytical Systems at Dublin City University, School of Physical Sciences, Dublin City University, Ireland; Federal University of São Carlos, Sorocaba, SP, Brazil.
| | - David J Kinahan
- FPC@DCU - Fraunhofer Project Centre for Embedded Bioanalytical Systems at Dublin City University, School of Physical Sciences, Dublin City University, Ireland
| | - Rohit Mishra
- FPC@DCU - Fraunhofer Project Centre for Embedded Bioanalytical Systems at Dublin City University, School of Physical Sciences, Dublin City University, Ireland
| | - Faith Mangwanya
- FPC@DCU - Fraunhofer Project Centre for Embedded Bioanalytical Systems at Dublin City University, School of Physical Sciences, Dublin City University, Ireland
| | - Niamh Kilcawley
- FPC@DCU - Fraunhofer Project Centre for Embedded Bioanalytical Systems at Dublin City University, School of Physical Sciences, Dublin City University, Ireland
| | | | - Jens Ducrée
- FPC@DCU - Fraunhofer Project Centre for Embedded Bioanalytical Systems at Dublin City University, School of Physical Sciences, Dublin City University, Ireland.
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17
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Torres Delgado SM, Kinahan DJ, Nirupa Julius LA, Mallette A, Ardila DS, Mishra R, Miyazaki CM, Korvink JG, Ducrée J, Mager D. Wirelessly powered and remotely controlled valve-array for highly multiplexed analytical assay automation on a centrifugal microfluidic platform. Biosens Bioelectron 2018; 109:214-223. [PMID: 29567566 DOI: 10.1016/j.bios.2018.03.012] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2017] [Revised: 02/09/2018] [Accepted: 03/06/2018] [Indexed: 12/14/2022]
Abstract
In this paper we present a wirelessly powered array of 128 centrifugo-pneumatic valves that can be thermally actuated on demand during spinning. The valves can either be triggered by a predefined protocol, wireless signal transmission via Bluetooth, or in response to a sensor monitoring a parameter like the temperature, or homogeneity of the dispersion. Upon activation of a resistive heater, a low-melting membrane (Parafilm™) is removed to vent an entrapped gas pocket, thus letting the incoming liquid wet an intermediate dissolvable film and thereby open the valve. The proposed system allows up to 12 heaters to be activated in parallel, with a response time below 3 s, potentially resulting in 128 actuated valves in under 30 s. We demonstrate, with three examples of common and standard procedures, how the proposed technology could become a powerful tool for implementing diagnostic assays on Lab-on-a-Disc. First, we implement wireless actuation of 64 valves during rotation in a freely programmable sequence, or upon user input in real time. Then, we show a closed-loop centrifugal flow control sequence for which the state of mixing of reagents, evaluated from stroboscopically recorded images, triggers the opening of the valves. In our last experiment, valving and closed-loop control are used to facilitate centrifugal processing of whole blood.
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Affiliation(s)
- Saraí M Torres Delgado
- Laboratory for Simulation, Department of Microsystems Engineering (IMTEK), University of Freiburg, Georges-Koehler-Allee 103, Freiburg im Breisgau 79110, Germany; Institute of Microstructure Technology, Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, Eggenstein-Leopoldshafen 76344, Germany
| | - David J Kinahan
- FPC@DCU - Fraunhofer Project Centre for Embedded Bioanalytical Systems at Dublin City University, Glasnevin, Dublin 9, Ireland.
| | - Lourdes Albina Nirupa Julius
- FPC@DCU - Fraunhofer Project Centre for Embedded Bioanalytical Systems at Dublin City University, Glasnevin, Dublin 9, Ireland
| | - Adam Mallette
- FPC@DCU - Fraunhofer Project Centre for Embedded Bioanalytical Systems at Dublin City University, Glasnevin, Dublin 9, Ireland; Department of Chemical and Biomolecular Engineering, University of Notre Dame, Notre Dame, IN, United States
| | - David Sáenz Ardila
- Laboratory for Simulation, Department of Microsystems Engineering (IMTEK), University of Freiburg, Georges-Koehler-Allee 103, Freiburg im Breisgau 79110, Germany
| | - Rohit Mishra
- FPC@DCU - Fraunhofer Project Centre for Embedded Bioanalytical Systems at Dublin City University, Glasnevin, Dublin 9, Ireland
| | - Celina M Miyazaki
- FPC@DCU - Fraunhofer Project Centre for Embedded Bioanalytical Systems at Dublin City University, Glasnevin, Dublin 9, Ireland; Science and Technology Centre for Sustainability, Federal University of São Carlos, Campus Sorocaba, SP, Brazil
| | - Jan G Korvink
- Institute of Microstructure Technology, Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, Eggenstein-Leopoldshafen 76344, Germany
| | - Jens Ducrée
- FPC@DCU - Fraunhofer Project Centre for Embedded Bioanalytical Systems at Dublin City University, Glasnevin, Dublin 9, Ireland
| | - Dario Mager
- Institute of Microstructure Technology, Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, Eggenstein-Leopoldshafen 76344, Germany
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18
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Walsh DI, Kong DS, Murthy SK, Carr PA. Enabling Microfluidics: from Clean Rooms to Makerspaces. Trends Biotechnol 2017; 35:383-392. [PMID: 28162773 PMCID: PMC6812491 DOI: 10.1016/j.tibtech.2017.01.001] [Citation(s) in RCA: 95] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2016] [Revised: 12/22/2016] [Accepted: 01/03/2017] [Indexed: 12/20/2022]
Abstract
The traditional requirement for clean rooms and specialized skills has inhibited many biologists from pursuing new microfluidic innovations. Makerspaces provide a growing alternative to clean rooms: they provide low-cost access to fabrication equipment such as laser cutters, plotter cutters, and 3D printers; use commercially available materials; and attract a diverse community of product designers. This Opinion discusses the materials, tools, and building methodologies particularly suited for developing novel microfluidic devices in these spaces, with insight into biological applications and leveraging the maker community. The lower barrier to access of makerspaces ameliorates the otherwise poor accessibility and scalability of microfluidic prototyping.
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Affiliation(s)
- David I Walsh
- Massachusetts Institute of Technology Lincoln Laboratory, Massachusetts Institute of Technology, Lexington, MA, USA.
| | - David S Kong
- Massachusetts Institute of Technology Lincoln Laboratory, Massachusetts Institute of Technology, Lexington, MA, USA
| | - Shashi K Murthy
- Department of Chemical Engineering, Northeastern University, Boston, MA, USA; Barnett Institute of Chemical and Biological Analysis, Northeastern University, Boston, MA, USA
| | - Peter A Carr
- Massachusetts Institute of Technology Lincoln Laboratory, Massachusetts Institute of Technology, Lexington, MA, USA.
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19
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Kinahan DJ, Renou M, Kurzbuch D, Kilcawley NA, Bailey É, Glynn MT, McDonagh C, Ducrée J. Baking Powder Actuated Centrifugo-Pneumatic Valving for Automation of Multi-Step Bioassays. MICROMACHINES 2016; 7:E175. [PMID: 30404349 PMCID: PMC6189914 DOI: 10.3390/mi7100175] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/04/2016] [Revised: 09/04/2016] [Accepted: 09/19/2016] [Indexed: 01/01/2023]
Abstract
We report a new flow control method for centrifugal microfluidic systems; CO₂ is released from on-board stored baking powder upon contact with an ancillary liquid. The elevated pressure generated drives the sample into a dead-end pneumatic chamber sealed by a dissolvable film (DF). This liquid incursion wets and dissolves the DF, thus opening the valve. The activation pressure of the DF valve can be tuned by the geometry of the channel upstream of the DF membrane. Through pneumatic coupling with properly dimensioned disc architecture, we established serial cascading of valves, even at a constant spin rate. Similarly, we demonstrate sequential actuation of valves by dividing the disc into a number of distinct pneumatic chambers (separated by DF membranes). Opening these DFs, typically through arrival of a liquid to that location on a disc, permits pressurization of these chambers. This barrier-based scheme provides robust and strictly ordered valve actuation, which is demonstrated by the automation of a multi-step/multi-reagent DNA-based hybridization assay.
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Affiliation(s)
- David J Kinahan
- School of Physical Sciences, Dublin City University, Glasnevin, Dublin 9, Ireland.
- Biomedical Diagnostics Institute, Dublin City University, Glasnevin, Dublin 9, Ireland.
| | - Marine Renou
- School of Physical Sciences, Dublin City University, Glasnevin, Dublin 9, Ireland.
- Biomedical Diagnostics Institute, Dublin City University, Glasnevin, Dublin 9, Ireland.
- Telecom Physique Strasbourg, Université de Strasbourg, Strasboug CS 10413, France.
| | - Dirk Kurzbuch
- School of Physical Sciences, Dublin City University, Glasnevin, Dublin 9, Ireland.
- Biomedical Diagnostics Institute, Dublin City University, Glasnevin, Dublin 9, Ireland.
| | - Niamh A Kilcawley
- School of Physical Sciences, Dublin City University, Glasnevin, Dublin 9, Ireland.
- Biomedical Diagnostics Institute, Dublin City University, Glasnevin, Dublin 9, Ireland.
| | - Éanna Bailey
- School of Physical Sciences, Dublin City University, Glasnevin, Dublin 9, Ireland.
- Biomedical Diagnostics Institute, Dublin City University, Glasnevin, Dublin 9, Ireland.
| | - Macdara T Glynn
- School of Physical Sciences, Dublin City University, Glasnevin, Dublin 9, Ireland.
- Biomedical Diagnostics Institute, Dublin City University, Glasnevin, Dublin 9, Ireland.
| | - Colette McDonagh
- School of Physical Sciences, Dublin City University, Glasnevin, Dublin 9, Ireland.
- Biomedical Diagnostics Institute, Dublin City University, Glasnevin, Dublin 9, Ireland.
| | - Jens Ducrée
- School of Physical Sciences, Dublin City University, Glasnevin, Dublin 9, Ireland.
- Biomedical Diagnostics Institute, Dublin City University, Glasnevin, Dublin 9, Ireland.
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