ANNALES UNIVERSITATIS TURKUENSIS ANNALES UNIVERSITATIS A I 575 Etvi Juntunen Etvi LATERAL FLOW IMMUNOASSAYS WITH FLUORESCENT REPORTER TECHNOLOGIES Etvi Juntunen ISBN 978-951-29-7126-8 (PRINT) , Finland 2018 Turku Painosalama Oy, ISBN 978-951-29-7127-5 (PDF) TURUN YLIOPISTON JULKAISUJA – ANNALES UNIVERSITATIS TURKUENSIS ISSN 0082-7002 (PRINT) | ISSN 2343-3175 (ONLINE) Sarja – ser. AI osa – tom. 575 | Astronomica – Chemica – Physica – Mathematica | Turku 2018 LATERAL FLOW IMMUNOASSAYS WITH FLUORESCENT REPORTER TECHNOLOGIES Etvi Juntunen TURUN YLIOPISTON JULKAISUJA – ANNALES UNIVERSITATIS TURKUENSIS Sarja - ser. A I osa - tom. 575 | Astronomica - Chemica - Physica - Mathematica | Turku 2018 University of Turku Faculty of Science and Engineering Department of Biochemistry Molecular Biotechnology and Diagnostics Doctoral Programme in Molecular Life Sciences Supervised by Professor Kim Pettersson, PhD Professor Tero Soukka, PhD Department of Biochemistry Department of Biochemistry Molecular Biotechnology and Diagnostics Molecular Biotechnology and Diagnostics University of Turku University of Turku Turku, Finland Turku, Finland Reviewed by Adjunct Professor Senior scientist Petri Ihalainen, PhD Aart van Amerongen, PhD MetGen Oy Wageningen University & Research Kaarina, Finland Wageningen, Netherlands Opponent Professor Richard O’Kennedy, Ph.D. Vice president for research Hamad Bin Khalifa University Doha, Qatar Cover image by author The originality of this thesis has been checked in accordance with the University of Turku quality assurance system using the Turnitin OriginalityCheck service. ISBN 978-951-29-7126-8 (PRINT) ISBN 978-951-29-7127-5 (PDF) ISSN 0082-7002 (PRINT) ISSN 2343-3175 (ONLINE) Painosalama Oy - Turku, Finland 2017 “If you hit a wrong note, it's the next note that you play that determines if its's good or bad.” –Miles Davis Contents CONTENTS List of original publications .......................................................................................... 7 Abbreviations ................................................................................................................ 8 Abstract ........................................................................................................................ 10 Tiivistelmä ................................................................................................................... 12 1 Introduction ........................................................................................................... 14 2 Review of the literature .......................................................................................... 16 2.1 Lateral flow assays ..................................................................................................... 16 2.1.1 From discovery of capillary action to biochemical assays .......................... 18 2.1.2 Lateral flow market segments ...................................................................... 19 2.1.3 Principle structure and function .................................................................. 20 2.1.4 Reporter particles .......................................................................................... 28 2.1.5 The advantages and limitations of the LF-platform .................................. 31 2.2 Fluorescent reporter particles .................................................................................. 33 2.2.1 Common characteristics ............................................................................... 33 2.2.2 Quantitative lateral flow assays .................................................................. 35 2.2.3 Calibration .................................................................................................... 37 2.2.4 Working range, signal variation and errors ............................................... 38 2.3 Commercial LFAs with fluorescent reporters ....................................................... 40 2.3.1 Assays with FDA 510(k)-clearance ............................................................. 40 2.3.2 Assays without FDA 510(k) clearance ........................................................ 41 2.3.3 Reporter technologies .................................................................................... 41 2.4 Reader devices for lateral flow assays ..................................................................... 42 2.4.1 Requirements for reader devices .................................................................. 43 2.4.2 Principles of optical measurement ............................................................... 45 2.4.3 Sensor technologies ....................................................................................... 46 2.4.4 Mobile device applications ........................................................................... 48 2.5 Feasibility for rapid diagnostic testing ................................................................... 49 2.5.1 Characteristics of the point-of-care conditions ........................................... 49 4 Contents 2.5.2 Sample matrices ............................................................................................ 50 2.5.3 Easy assay procedure .................................................................................... 51 2.5.4 RDTs and biosafety ...................................................................................... 52 2.5.5 Cost of the assays .......................................................................................... 52 3 Aims of the study ................................................................................................... 54 4 Summary of materials and methods ..................................................................... 55 4.1 Reporter particles ...................................................................................................... 55 4.1.1 Bioconjugation of reporter particles with binder molecules ...................... 55 4.1.2 Upconverting nanoparticles ......................................................................... 55 4.1.3 Eu(III) nanoparticles .................................................................................... 56 4.1.4 Colloidal gold ................................................................................................ 57 4.2 Preparation of LFIA strips ....................................................................................... 57 4.2.1 Strip membrane assembly ............................................................................ 57 4.2.2 Dispensing of binder lines and strip cutting ................................................ 58 4.3 Sample materials ....................................................................................................... 59 4.3.1 Buffer-based calibrators ............................................................................... 59 4.3.2 Serum and plasma ........................................................................................ 59 4.3.3 Whole blood .................................................................................................. 60 4.4 LFIA procedure ......................................................................................................... 60 4.4.1 Fluid absorption sequence ............................................................................ 60 4.4.2 Measurements and data interpretation ...................................................... 61 4.5 Microparticle-based assay platform ........................................................................ 63 4.5.1 Assay cassette ................................................................................................ 63 4.5.2 Capture microparticle bioconjugation ........................................................ 63 4.5.3 Assay procedure ............................................................................................ 64 4.5.4 Signal detection ............................................................................................. 64 5 Summary of results and discussion ....................................................................... 65 5.1 Reporter particles ...................................................................................................... 65 5.1.1 Colloidal gold versus luminescent reporters ................................................ 65 5.1.2 Measurement mode of Eu(III)-nanoparticles ............................................. 65 5.1.3 Measurement of UCNP-reporters ................................................................ 67 5 Contents 5.1.4 Performance of lateral flow assays .............................................................. 68 5.2 Assay platforms ......................................................................................................... 69 5.2.1 Lateral flow assay platform .......................................................................... 69 5.2.2 Microparticle-based assay platform ............................................................ 71 6 Conclusions ............................................................................................................ 73 Acknowledgements ..................................................................................................... 75 References .................................................................................................................... 77 Original publications .................................................................................................. 95 6 List of original