title: Microfluidic chip to produce temperature jumps for electrophysiology.
abstract: We developed a microfluidic chip that provides rapid temperature changes and accurate temperature control of the perfusing solution to facilitate patch-clamp studies. The device consists of a fluid channel connected to an accessible reservoir for cell culture and patch-clamp measurements. A thin-film platinum heater was placed in the flow channel to generate rapid temperature change, and the temperature was monitored using a thin-film resistor. We constructed the thermal chip using SU-8 on a glass wafer to minimize the heat loss. The chip is capable of increasing the solution temperature from bath temperature (20 degrees C) to 80 degrees C at an optimum heating rate of 0.5 degrees C/ms. To demonstrate the ability of the thermal chip, we have conducted on-chip patch-clamp recordings of temperature-sensitive ion channels (TRPV1) transfected HEK293 cells. The heat-stimulated currents were observed using whole-cell and cell-attached patch configurations. The results demonstrated that the chip can provide rapid temperature jumps at the resolution of single-ion channels.
authors.affiliation: Department of Mechanical and Aerospace Engineering, State University of New York-Buffalo, Buffalo, New York 14260, USA.
authors.forename: Thomas
authors.initials: T
authors.lastname: Pennell
authors.forename: Thomas
authors.initials: T
authors.lastname: Suchyna
authors.forename: Jianbin
authors.initials: J
authors.lastname: Wang
authors.forename: Jinseok
authors.initials: J
authors.lastname: Heo
authors.forename: James D
authors.initials: JD
authors.lastname: Felske
authors.forename: Frederick
authors.initials: F
authors.lastname: Sachs
authors.forename: Susan Z
authors.initials: SZ
authors.lastname: Hua
mesh_terms: D002138:Calibration; D002460:Cell Line; D004594:Electrophysiology; D006801:Humans; D046210:Microfluidic Analytical Techniques / Q000295:instrumentation* / Q000379:methods*; D008855:Microscopy, Electron, Scanning; D018408:Patch-Clamp Techniques; D013696:Temperature