Quirks and Quarks

A wasp's gruesome egg-laying organ inspires a new medical tool

An instrument based on the insect's ovipositor could do biopsies, remove tumours or deliver drugs

An instrument based on the insect's ovipositor could do biopsies, remove tumours or deliver drugs

Parasitic wasp with ovipositor embedded below. (WUR)

The egg-laying technique of parasitic wasps is the inspiration behind the design of a new medical tool that could provide minimally invasive ways to remove blood clots or cancerous tissues, or deliver drugs.

Many species of parasitic wasps lay eggs in insects and plants, sometimes having to punch deep through tissue or wood in order to deposit their offspring in a safe place in which they develop — often eating their living nursery from the inside out.

To deposit their eggs, the wasps have a long, flexible ovipositor with a unique bladed tip that can cut into their victim, and through which eggs can pass. 

This behaviour of the wasp caught the attention of Aimee Sakes, an assistant professor of biomechanical engineering and part of the Bio-Inspired Technology Group (BITE) at Delft University of Technology in the Netherlands

At the tip of the wasp's delicate tubelike ovipositor are three semicircular blades that slide independently in sequence to cut into tissue and draw the ovipositor deeper. This cutting motion is the inspiration for the device.

Surgical tool inspired by the egg-laying organ of a parasitic wasp. (Aimee Sakes)

The prototype tool has six blades, but it works in a similar way to cut into tissue.  It's tubelike structure can be used to remove tissue from its target, or deposit material into it. It's been successfully tested on tissue substitutes including gelatin and mince meat, but not yet on living tissue.

This bio-inspired tool could reach places that are difficult for traditional surgery. It would also be less invasive than surgery, which could means less trauma and quicker recovery time for patients.