title: Hydrodynamic gating for sample introduction on a microfluidic chip.
abstract: We present a microfluidic sample introduction approach based on a novel flow control mechanism, hydrodynamic gated injection. It has the advantages of easy and flexible flow control, similar to its analog, electrokinetic gated injection, but exhibits the unique properties of strong driving force and good biocompatibility, ideal for applications involving live biological samples. Theories for hydrodynamic gating were proposed and validated by both numerical simulations and flow visualization experiments. An investigation with fluorescein revealed that pico-liter samples can be injected with high repeatability (RSD <1.9%). Selective injections of GFP-transfected nematode eggs were demonstrated with a survival rate of >95%. We expect the developed method to be potentially useful for microfluidic cell and organism analysis, either as a sample introduction module or a stand-alone analyzer.
authors.affiliation: Britton Chance Center for Biomedical Photonics at Wuhan National Laboratory for Optoelectronics - Hubei Bioinformatics & Molecular Imaging Key Laboratory, Department of Systems Biology, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, 430074, China.
authors.forename: Pu
authors.initials: P
authors.lastname: Chen
authors.forename: Xiaojun
authors.initials: X
authors.lastname: Feng
authors.forename: Jian
authors.initials: J
authors.lastname: Sun
authors.forename: Ying
authors.initials: Y
authors.lastname: Wang
authors.forename: Wei
authors.initials: W
authors.lastname: Du
authors.forename: Bi-Feng
authors.initials: BF
authors.lastname: Liu
mesh_terms: D004867:Equipment Design; D019544:Equipment Failure Analysis; D017022:Flow Injection Analysis / Q000295:instrumentation*; D046210:Microfluidic Analytical Techniques / Q000295:instrumentation*; D008846:Micromanipulation / Q000295:instrumentation*; D013048:Specimen Handling / Q000295:instrumentation*