Research On The AC Electrokinetic Properties And Self-assembly Of Gold Coated Microparticles

With the rapid deve lopment o f Micro-Electro-Mechanical Syste ms (MEMS)processing technology, microfluid ics as a high and new techno logy rise rapid ly,and has great potentia l in ma ny areas, such as ana lytica l biochemistr y, diseasedetection, enviro nmenta l monitoring, etc. The micro-nano partic les manipulationtechnology based on the AC electric field, such as die lectrophoresis(DEP) andelectrorotation(ROT), has had mature theory and a wide range of applicatio ns inmanip ulating micro-nano biologica l particles precise ly. However, the ACelectric fie ld manip ulatio n mechanis m for a good conductor micro-nano partic leis serio usly lack of a systematic research, which severely limits its furtherdeve lopment and application.This thesis focuses on the AC electrokinetic research of go ld coatedpartic les, summarizes the present research situatio n of partic le manipulation a llover the world, analyses the basic theories of DEP and ROT, fo unds the ACelectrokinetic properties mathe matics model of a gold coated partic le, revealsthe AC electr ic fie ld ma nipulat ion mechanis m from the perspective of theelectric double layer, calculates its DEP force equation, ROT torque and angularspeed equation.Based on the theoretica l analys is, quadrupole electrodes and paralle l-plateelectrodes are chosen as experime nt chips, a2D COMSOL s imulation model isfounded, the fie ld and DEP force distr ibuted in experiment s ystem are simulated,the microwire self-assemb ly mechanis m is ana lyzed, and the doma in factors ofROT angular speed are studied quantitative ly through MATLAB, such asfrequency, vo ltage, solution conductivity, etc.Different dime ns ions, different shapes gold coated particles and experime ntchips are designed and manufactured. ROT and microwire self-assemb lyexperiments of go ld coated micropartic les are carr ied out, and the experimentphenomeno n is exp lained.