Ultrasonic Device Cleans Medical Instruments Better

A new study describes an ultrasonic device that creates tiny bubbles that scrub medical device surfaces, thus reducing the need for additives and heating to achieve effective cleaning.

The StarStream device, developed by researchers at the University of Southampton (United Kingdom), is used to stream free-flowing water containing an electrolyte (Na2SO4) and a diluted surfactant concentration (2 mMol SDS). The water is gently streamed through a special nozzle that causes electrolysis of the water, thus generating an electrochemical bubble swarm (EBS) of tiny bubbles of hydrogen and oxygen, which dramatically improve the cleaning power of the water. The surfactant is employed to maintain the average size of the bubbles to 100 μm diameter within the swarm.


The EBS also perturbs an acoustic ultrasonic transmission through the stream, which in order to optimize the cleaning process is pulsed and synchronized with electrochemical current, but with different duty cycles. The cleaning action was shown on structured surfaces loaded with fluorescent particles, demonstrating significantly enhanced cleaning compared to that found with an inherent bubble population produced by the flow and acoustic regime alone, under the same conditions. The study describing the StarStream device was published on August 12, 2015, in Physical Chemistry Chemical Physics.

“In the absence of sufficient cleaning of medical instruments, contamination and infection can result in serious consequences for the health sector and remains a significant challenge,” said lead author Prof. Tim Leighton, PhD, of the Institute of Sound and Vibration Research. “Our highly-effective cleaning device, achieved with cold water and without the need for chemical additives or the high power consumption associated with conventional strategies, has the potential to meet this challenge and transform the sector.”

The device is also cost-effective; it can save an estimated 79%–97% of the energy used in current commercial products and also recycles water, thus savings 83%–99% of the water used. It is now being commercialized by Ultrawave (South Glamorgan, United Kingdom).

Related Links:
University of Southampton
Ultrawave