Cell docking and on-chip monitoring of cellular reactions with a controlled concentration gradient on a microfluidic device.
We have developed a microfluidic device for on-chip monitoring of cellular reactions. The device consists of two primary analytical functions: control of cell transport and immobilization, and dilution of an analyte solution to generate a concentration gradient. In this device, a dam structure in parallel to the fluid flow was constructed for docking and alignment of biological cells, which allows the fragile cells to move in the microfluidic channels and to be immobilized with controllable numbers in desired locations. The cells docked on the parallel dam structure are exposed to minimal stress caused by fluidic pressure. Additionally, a network of microfluidic channels was designed to generate a concentration gradient by controlled fluid distribution and diffusive mixing. An analyte solution could be diluted to different gradients as a function of distance along the dam. We used the ATP-dependent calcium uptake reaction of HL-60 cells as a model for on-chip measurement of the threshold ATP concentration that induces significant intracellular calcium signal. The results have demonstrated the feasibility of using the microchip for real-time monitoring of cellular processes upon treatment of a concentration gradient of a test solution. The integration of cell manipulation and solution manipulation on a microchip allows the measurement of concentration-dependent biological responses within a confined microscale feature.
Applied Research Centre for Genomic Technology and Department of Biology and Chemistry, City University of Hong Kong, Kowloon, Hong Kong SAR, China. bhmyang@cityu.edu.hk
Mengsu
M
Yang
Cheuk-Wing
CW
Li
Jun
J
Yang
D000255:Adenosine Triphosphate / Q000494:pharmacology; D020013:Calcium Signaling / Q000187:drug effects; D003584:Cytological Techniques / Q000295:instrumentation*; D004305:Dose-Response Relationship, Drug; D018922:HL-60 Cells; D006801:Humans; D008904:Miniaturization
D000255:Adenosine Triphosphate