Wirelessly addressable heater array for centrifugal microfluidics and Escherichia coli sterilization

Area of Science:

• Microfluidics
• Biomedical Engineering
• Radiofrequency Engineering

Background:

• Localized temperature control is a significant challenge in centrifugal microfluidics and lab-on-a-chip systems.
• Existing heating methods often lack selectivity and integration capabilities.

Purpose of the Study:

• To present a new wireless heating method for selective activation of micropatterned resonant heaters.
• To demonstrate the applicability of this method in centrifugal microfluidic systems and for sterilization.

Main Methods:

• Utilized external radiofrequency (RF) fields to selectively activate an array of wireless heaters by modulating the field frequency.
• Achieved targeted heating of individual micropatterned resonant heaters.
• Demonstrated heating under high-speed spinning conditions.

Main Results:

• Successfully achieved a temperature of 93 °C in the heater with 0.49-W RF output power.
• Validated the wireless heating method's effectiveness in centrifugal systems at high speeds.
• Demonstrated selective sterilization of Escherichia coli using the wireless heating technique.

Conclusions:

• The developed wireless heating method offers precise, selective temperature control for microfluidic devices.
• This technology shows significant promise for healthcare applications, particularly in sterilization and centrifugal systems.