| Microfluidics and polymer MEMS are the most promising technologies to realize biochemical analysis systems on a chip with low cost, tiny fluid sample, fast chemical/biochemical reaction, and high detection accuracy capabilities. Sample processing, chemical/biochemical reaction, and sample detection are considered as the three major tasks required for lab-on-a-chips. Micropumps, microvalves and micromixers are also considered as key components in handling microfluidics in the lab-on-a-chips. There have been numerous efforts to develop on-chip active micropumps and microvalves. However, the realization of active microfluidic components in an on-chip disposable platform has been considered as one of the most difficult tasks in terms of fabrication, system integration, reliability, and cost. Consequently, the development of passive microfluidic components is a good alternative to the active components if they can provide the same level of functionality.; The objective of this research is to develop a smart in-plane passive microfluidic mixer and on-chip pressure sources (e.g., air-bursting detonator or functional pressure generator using solid propellant), which are important components in realizing lab-on-a chips in a disposable platform. All of the developed microfluidic components in this field are fabricated on plastic substrates using polymer MEMS technologies. In this thesis, an innovative in-plane passive micromixer using the "Coanda effect" has been designed, simulated, fabricated and then fully characterized. Due to the simple in-plane structure of the novel micromixer explored in this work, the mixer can be easily realized and integrated with on-chip microfluidic devices or lab-on-a-chip systems. In addition, as alternative ways to the active micropump for generating pressure, on-chip disposable pressure generators using either micro pneumatic energy (disposable on-chip air-bursting detonator) or thermal-chemical energy (functional on-chip pressure generator) have been designed, simulated, fabricated and fully characterized. Due to their low cost, compact structure, and functional response, they are useful alternative power sources to drive fluid samples in disposable lab-on-a-chip devices, biochips, and point-of-care systems.; Finally, the microfluidic approaches and devices developed in this work have been applied to the development of a smart disposable polymer lab-on-a-chip for clinical diagnostics, which has sampling and analysis capabilities for human whole blood.; In this thesis, new on-chip passive fluidic micromixer and pressure generator for lab-on-a-chips have been successfully realized in a disposable platform and then applied to the smart disposable polymer lab-on-a-chips for clinical diagnostics. |
