Applications of microfluidic chips in optical manipulation & photoporation

Microfluidic devices;Biochips;Optical tweezers;Transfection

Marchington, Robert F. ; Dholakia, Kishan ; Dholakia, Kishan

University:University of St Andrews

Department:Physics & Astronomy (School of)

关键词: Microfluidic devices;    Biochips;    Optical tweezers;    Transfection;   

Others  :  https://research-repository.st-andrews.ac.uk/bitstream/handle/10023/1633/Robert%20Marchington%20PhD%20thesis.PDF?sequence=3&isAllowed=y

来源: DR-NTU

【 摘 要 】

Integration and miniaturisation in electronics has undoubtedly revolutionised themodern world. In biotechnology, emerging lab-on-a-chip (LOC) methodologies promise all-integrated laboratory processes, to perform complete biochemical or medicalsynthesis and analysis encapsulated on small microchips. The integration of electrical, optical and physical sensors, and control devices, with fluid handling, is creatinga new class of functional chip-based systems. Scaled down onto a chip, reagent andsample consumption is reduced, point-of-care or in-the-field usage is enabled throughportability, costs are reduced, automation increases the ease of use, and favourablescaling laws can be exploited, such as improved fluid control. The capacity to manipulate single cells on-chip has applications across the life sciences, in biotechnology,pharmacology, medical diagnostics and drug discovery.This thesis explores multiple applications of optical manipulation within microfluidic chips. Used in combination with microfluidic systems, optics adds powerfulfunctionalities to emerging LOC technologies. These include particle managementsuch as immobilising, sorting, concentrating, and transportation of cell-sized objects,along with sensing, spectroscopic interrogation, and cell treatment.The work in this thesis brings several key applications of optical techniquesfor manipulating and porating cell-sized microscopic particles to within microfluidicchips. The fields of optical trapping, optical tweezers and optical sorting are reviewedin the context of lab-on-a-chip application, and the physics of the laminar fluid flowexhibited at this size scale is detailed. Microfluidic chip fabrication methods arepresented, including a robust method for the introduction of optical fibres for laserbeam delivery, which is demonstrated in a dual-beam optical trap chip and in opticalchromatography using photonic crystal fibre. The use of a total internal reflection microscope objective lens is utilised in anovel demonstration of propelling particles within fluid flow. The size and refractiveindex dependency is modelled and experimentally characterised, before presentingcontinuous passive optical sorting of microparticles based on these intrinsic opticalproperties, in a microfluidic chip.Finally, a microfluidic system is utilised in the delivery of mammalian cells to afocused femtosecond laser beam for continuous, high throughput photoporation. Theoptical injection efficiency of inserting a fluorescent dye is determined and the cellviability is evaluated. This could form the basis for ultra-high throughput, efficienttransfection of cells, with the advantages of single cell treatment and unrivalledviability using this optical technique.