Measurement of the Thermal Effect of Standing Surface Acoustic Waves in Microchannel by Fluoresence Intensity

Abstract

Temperature is an important parameter for many medical and biological applications. It is key to measuring the temperature of acoustofluidics devices for controlling the device’s temperature. In this paper, Rhodamine B was used to measure the temperature change of the microchannel induced by the SSAWs’ thermal effect in microfluidics. A thermocouple was integrated into the microfluidics device to calibrate the relationship between the fluorescent intensity ratios of Rhodamine B and the temperature. Then, the fluid temperature in the microchannel heated by the SSAWs was measured by the fluorescent signal intensity ratio in the acoustofluidics device. The fluid temperature with different input voltages and different flow rates was measured. The results show that SSAWs can heat the still fluid rapidly to 80 °c, and the flow rates will influence the temperature of the fluid. The results will be useful for precisely controlling the temperature of acoustofluidics devices.

Enhanced Performance of an Acoustofluidic Device by Integrating Temperature Control

“…In a paper published in 2021, a tracer dye was used to measure the temperature change in a microchannel induced by the thermal effect of standing surface acoustic waves (SSAWs) in microfluidics. The results show that SSAWs can heat the immobile fluid rapidly to 80 • C and that the flow rates can influence the temperature of the liquid [14]. Furthermore, the temperature of the liquid in the microchannel rises as the input voltage increases [15].…”

Bisymmetric coherent acoustic tweezers based on modulation of surface acoustic waves for dynamic and reconfigurable cluster manipulation of particles and cells

“…20,21 Although some recent works have indicated that under specific interdigital transducer (IDT) configurations (e.g., high excitation frequency, high input power, long excitation time, and near placement), the temperature within the microfluidic chamber can increase rapidly over a short period of time. 22,23 This can be completely avoided by preliminary device design and realtime regulation of the experimental parameters, 24 preventing irreversible damage to the treated biological samples from acoustic thermal effects. Therefore, acoustic tweezers could be a promising strategy for the applications of manipulation of microparticles and cells in clinical diagnosis, 25 dynamic cell assembly, 26 and oriented alignment of suspended bioparticles.…”

Thermodynamic Characterization of a Highly Transparent Microfluidic Chip with Multiple On-Chip Temperature Control Units

“…The miniaturization and integration of microfluidic devices could greatly reduce contamination and increase the efficiency of time, energy and material consumption, especially for many on-site working conditions outside a professional lab [8]. Temperature control is widely required in microfluidic systems that are designed for bioengineering analyses, forensic identifications, cryopreservation studies and chemical synthesis [9][10][11][12][13][14]. For example, PCR is a commonly used bioanalytical technique that amplifies a specific DNA segment from a few copies into several million copies within a few hours in vitro.…”