Medical Research Council - London Institute of Medical Sciences

Now in our 8th year of bringing you beautiful imagery from biomedical science every day

Popping Sound

Inflating droplets with ultrasound could be used to make foams which better deliver topical medication

22 September 2018

Popping Sound

It’s a nightmare for bubble blowers – the moment when, instead of leaving a bubble wand, a wobbling nearly-bubble seems to change its mind and deflate – hurtling back towards a terrified face and a soapy pop. This unfortunate quirk of surface tension is reversed here, inflating droplets of a soapy substance using ultrasound, as a step towards transforming drug delivery. Acoustic vibrations cause the edge of the droplet to buckle and rise (top row). Resonating vibrations grow the bubble, and a split second later it floats away (bottom right). Adapting the technique for industry, ultrasound could be used to create pharmacological foams – increasingly used over creams to deliver topical drugs onto skin when treating conditions like dermatitis and psoriasis.

Written by John Ankers

Search The Archive

Submit An Image

What is BPoD?

BPoD stands for Biomedical Picture of the Day. Managed by the MRC London Institute of Medical Sciences the website aims to engage everyone, young and old, in the wonders of biomedicine. Images are kindly provided for inclusion on this website through the generosity of scientists across the globe.

Read More

BPoD is also available in Catalan at with translations by the University of Valencia.