%0 Journal Article
%T A High-Precision Micropipette Sensor for Cellular-Level Real-Time Thermal Characterization
%A Ramesh Shrestha
%A Tae-Youl Choi
%A Wonseok Chang
%A Donsik Kim
%J Sensors
%D 2011
%I MDPI AG
%R 10.3390/s110908826
%X We report herein development of a novel glass micropipette thermal sensor fabricated in a cost-effective manner, which is capable of measuring steady thermal fluctuation at spatial resolution of ~2 ¦Ìm with an accuracy of ¡À0.01 ¡ãC. We produced and tested various micrometer-sized sensors, ranging from 2 ¦Ìm to 30 ¦Ìm. The sensor comprises unleaded low-melting-point solder alloy (Sn-based) as a core metal inside a pulled borosilicate glass pipette and a thin film of nickel coating outside, creating a thermocouple junction at the tip. The sensor was calibrated using a thermally insulated calibration chamber, the temperature of which can be controlled with an accuracy of ¡À0.01 ¡ãC, and the thermoelectric power (Seebeck coefficient) of the sensor was recorded from 8.46 to 8.86 ¦ÌV/¡ãC. We have demonstrated the capability of measuring temperatures at a cellular level by inserting our temperature sensor into the membrane of a live retinal pigment epithelium cell subjected to a laser beam with a focal spot of 6 ¦Ìm. We measured transient temperature profiles and the maximum temperatures were in the range of 38¨C55 ¡À 0.5 ¡ãC.
%K micropipette
%K thermal sensor
%K cellular-level
%K laser
%U http://www.mdpi.com/1424-8220/11/9/8826