title: Thermo-optical characterization of fluorescent rhodamine B based temperature-sensitive nanosensors using a CMOS MEMS micro-hotplate.
abstract: A custom designed microelectromechanical systems (MEMS) micro-hotplate, capable of operating at high temperatures (up to 700 °C), was used to thermo-optically characterize fluorescent temperature-sensitive nanosensors. The nanosensors, 550 nm in diameter, are composed of temperature-sensitive rhodamine B (RhB) fluorophore which was conjugated to an inert silica sol-gel matrix. Temperature-sensitive nanosensors were dispersed and dried across the surface of the MEMS micro-hotplate, which was mounted in the slide holder of a fluorescence confocal microscope. Through electrical control of the MEMS micro-hotplate, temperature induced changes in fluorescence intensity of the nanosensors was measured over a wide temperature range. The fluorescence response of all nanosensors dispersed across the surface of the MEMS device was found to decrease in an exponential manner by 94%, when the temperature was increased from 25 °C to 145 °C. The fluorescence response of all dispersed nanosensors across the whole surface of the MEMS device and individual nanosensors, using line profile analysis, were not statistically different (p< 0.05). The MEMS device used for this study could prove to be a reliable, low cost, low power and high temperature micro-hotplate for the thermo-optical characterisation of sub-micron sized particles. The temperature-sensitive nanosensors could find potential application in the measurement of temperature in biological and micro-electrical systems.
authors.affiliation: Laboratory of Biophysics and Surface Analysis, School of Pharmacy, University of Nottingham, Boots Science Building, University Park, Nottingham NG7 2RD, UK.
authors.forename: Veeren M
authors.initials: VM
authors.lastname: Chauhan
authors.affiliation: Cambridge CMOS Sensors, Suite 820, 2nd Floor, St Andrews House, 59 St Andrews Street, Cambridge CB2 3BZ, UK.
authors.forename: Richard H
authors.initials: RH
authors.lastname: Hopper
authors.affiliation: Cambridge CMOS Sensors, Suite 820, 2nd Floor, St Andrews House, 59 St Andrews Street, Cambridge CB2 3BZ, UK.
authors.forename: Syed Z
authors.initials: SZ
authors.lastname: Ali
authors.affiliation: Advanced Microscopy Unit, School of Biomedical Sciences, University of Nottingham, Queens Medical Centre, Nottingham NG7 2UH, UK.
authors.forename: Emma M
authors.initials: EM
authors.lastname: King
authors.affiliation: Cambridge CMOS Sensors, Suite 820, 2nd Floor, St Andrews House, 59 St Andrews Street, Cambridge CB2 3BZ, UK ; Electrical Engineering Division, Engineering Department, University of Cambridge, 9 JJ Thomson Avenue, Cambridge CB3 0FA, UK.
authors.forename: Florin
authors.initials: F
authors.lastname: Udrea
authors.affiliation: Engineering, Faculty of Technology, De Montfort University, Queens Building, The Gateway, Leicester LE1 9BH, UK.
authors.forename: Chris H
authors.initials: CH
authors.lastname: Oxley
authors.affiliation: Laboratory of Biophysics and Surface Analysis, School of Pharmacy, University of Nottingham, Boots Science Building, University Park, Nottingham NG7 2RD, UK.
authors.forename: Jonathan W
authors.initials: JW
authors.lastname: Aylott
keywords: Fluorescent; MEMS micro-hotplate; Nanosensor; Rhodamine B; Silica sol–gel; Temperature-sensitive
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