title: A microfluidic device based on gravity and electric force driving for flow cytometry and fluorescence activated cell sorting.
abstract: A novel method based on gravity and electric force driving of cells was developed for flow cytometry and fluorescence activated cell sorting in a microfluidic chip system. In the experiments cells flowed spontaneously under their own gravity in a upright microchip, passed through the detection region and then entered into the sorting electric field one by one at an average velocity of 0.55 mm s(-1) and were fluorescence activated cell sorted (FACS) by a switch-off activation program. In order to study the dynamical and kinematic characteristics of single cells in gravity and electric field of microchannels a physical and numerical module based on Newton's Law of motion was established and optimized. Hydroxylpropylmethyl cellulose (HPMC) was used to minimize cell assembling, sedimentation and adsorption to microchannels. This system was applied to estimate the necrotic and apoptotic effects of ultraviolet (UV) light on HeLa cells by exposing them to UV radiation for 10, 20 or 40 min and the results showed that UV radiation induced membrane damage contributed to the apoptosis and necrosis of HeLa cells.
authors.affiliation: Department of Chemistry, Tsinghua University, Beijing 100084, China.
authors.forename: Bo
authors.initials: B
authors.lastname: Yao
authors.forename: Guo-an
authors.initials: GA
authors.lastname: Luo
authors.forename: Xue
authors.initials: X
authors.lastname: Feng
authors.forename: Wei
authors.initials: W
authors.lastname: Wang
authors.forename: Ling-xin
authors.initials: LX
authors.lastname: Chen
authors.forename: Yi-ming
authors.initials: YM
authors.lastname: Wang
mesh_terms: D017209:Apoptosis / Q000528:radiation effects*; D002452:Cell Count / Q000295:instrumentation / Q000379:methods; D018929:Cell Culture Techniques / Q000295:instrumentation* / Q000379:methods; D002465:Cell Movement / Q000502:physiology* / Q000528:radiation effects; D002469:Cell Separation / Q000295:instrumentation* / Q000379:methods; D004307:Dose-Response Relationship, Radiation; D004574:Electromagnetic Fields; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005434:Flow Cytometry / Q000295:instrumentation* / Q000379:methods; D006112:Gravitation; D006367:HeLa Cells; D006801:Humans; D046210:Microfluidic Analytical Techniques / Q000295:instrumentation* / Q000379:methods; D008846:Micromanipulation / Q000295:instrumentation* / Q000379:methods; D011829:Radiation Dosage; D013314:Stress, Mechanical; D014466:Ultraviolet Rays