title: An optofluidic temperature probe.
abstract: We report the application of a microfluidic device for semi-contact temperature measurement in picoliter volumes of aqueous media. Our device, a freely positionable multifunctional pipette, operates by a hydrodynamic confinement principle, i.e., by creating a virtual flow cell of micrometer dimensions within a greater aqueous volume. We utilized two fluorescent rhodamines, which exhibit different fluorescent responses with temperature, and made ratiometric intensity measurements. The temperature dependence of the intensity ratio was calibrated and used in a model study of the thermal activation of TRPV1 ion channels expressed in Chinese hamster ovary cells. Our approach represents a practical and robust solution to the specific problem of measuring temperature in biological experiments in vitro, involving highly localized heat generation, for example with an IR-B laser.
authors.affiliation: Department of Chemical and Biological Engineering, Chalmers University of Technology, Kemivägen 10, Göteborg SE-412 96, Sweden. ilona.wegrzyn@chalmers.se
authors.forename: Ilona
authors.initials: I
authors.lastname: Węgrzyn
authors.forename: Alar
authors.initials: A
authors.lastname: Ainla
authors.forename: Gavin David Michael
authors.initials: GD
authors.lastname: Jeffries
authors.forename: Aldo
authors.initials: A
authors.lastname: Jesorka
mesh_terms: D000818:Animals; D016466:CHO Cells; D002138:Calibration; D006224:Cricetinae; D003412:Cricetulus; D020342:Finite Element Analysis; D006358:Hot Temperature; D006801:Humans; D015640:Ion Channel Gating; D046210:Microfluidic Analytical Techniques / Q000295:instrumentation*; D055095:Optics and Photonics / Q000295:instrumentation*; D050916:TRPV Cation Channels / Q000378:metabolism; D013696:Temperature; D013821:Thermometers
chemical_list: D050916:TRPV Cation Channels; C494482:TRPV1 protein, human
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