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Ultrasound system solves the 'unsticking problem' in biomedical research

·31 min·2 clips

Trypsin, used since 1916 to unstick cells, can make anti-cancer drugs appear less effective or more toxic.

Luke Cox, co-founder and CEO of Impulsonics, explains the cell culture problem his company was founded to solve. When biological cells are grown in Petri dishes for drug discovery, biological research, or regenerative medicine, they adhere to the plastic surfaces (which have specialized coatings to encourage bonding) and to each other. Every few days, cells fill their container and must be 'passaged' -- detached and transferred to a new, larger container. The current standard technique uses trypsin, an enzyme first applied to cell subculturing in 1916, which cleaves the surface bonds that hold cells in place. However, trypsin also damages the surface receptors that cells use to interact with drugs, the immune system, and other parts of the body. Since 60% of clinical drugs interact with cell surface markers, trypsin treatment can systematically bias drug testing results -- either overestimating toxicity or underestimating efficacy of anti-cancer drugs, depending on which surface proteins are affected. For regenerative medicine cells, which must navigate the body and modulate the immune system using those same surface proteins, trypsin damage is even more consequential. Impulsonics' solution uses ultrasound to create controlled regions of high and low pressure that exert direct physical force on cells, combined with mild chemical cues that reduce stickiness, detaching cells without the enzymatic damage of trypsin. Cox explains that sound waves exert mechanical force -- just as they vibrate the eardrum -- and that precise control of the acoustic field allows selective, gentle detachment. The system can be simpler to automate than current trypsin-based workflows, which require centrifugation, liquid exchange, and multiple precision steps. Impulsonics spun out of the University of Bristol in 2023 and is targeting pharmaceutical, biotech, and regenerative medicine customers.

As heard by us

A practical cell-culture problem, handled with restraint and enough technical detail to be useful.

The episode follows an ultrasonic system built to stop living cells from clumping, and it keeps the focus on the practical problem instead of dressing it up.

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Why you'd press play

You want the science of cell culture without the usual lab-bench fog.

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