Micron-bubble streaming flow towards micron to sub-micron sized sorting

Microfluidics;sorting;micron-bubble

Yang, Rui ; Hilgenfeldt ; Sascha

关键词: Microfluidics;    sorting;    micron-bubble;   

Others  :  https://www.ideals.illinois.edu/bitstream/handle/2142/89091/YANG-THESIS-2015.pdf?sequence=1&isAllowed=y

美国|英语

来源: The Illinois Digital Environment for Access to Learning and Scholarship

【 摘 要 】

Micro-bubble streaming flows represent a unique type of actuating mechanism for microfluidics and have demonstrated great potential in the applications of micro-particle manipulation (e.g. size dependent trapping, sorting, and focusing etc.). The main object of this thesis work is to extend towards much smaller sized particle sorting down to 1μm and sub-micron. On top of that, we want to further explore the potential of applying bubble streaming sorting to biological objects which in the similar size scales. Systematical experiments have been conducted on polystyrene latex particles as well as several types biological cells and its infectious viruses, specifically Sulfolobus islandicus with Sulfolobus spindle-shaped viruses, and also Escherichia coli with Lambda phage. Size sensitive sorting has been revealed by means of larger sized objects will be majorly deflected away from their original streamline while smaller sized objects will follow, which leads to size-sensitive sorting. It has been proved that relative concentration ratio of two sized particle mixing solution can be enhanced with almost a factor of 6, and can be further improved by sequential bubble sorting. However, sorting application with smaller particles with diameter as 1μm and 100nm doesn’t perform as well as larger particles sorting reported by Wang et al. (Appl. Phys. Lett. 99, 034101, 2011) when they used a mixture of 10μm and 5μm particles in diameter. Fundamental reason of this can be explained by a combination of advection and diffusion effect. Beyond that, the principle of micro-bubble streaming sorting also has shown applicable to biological objects sorting purpose, but could be affected more by (i) wider size distribution, (ii) naturally morphologically diverse, (iii) active motion of live cells and (iv) more deformable compared to artificial polystyrene particles.