Bubble gun

Penetrating microjets in soft substrates: towards controlled needle-free injections

This website will be free of access and used for dissemination of results, updating about the progress of the project, BuBble Gun, financed by the European Research Council.

You can see some information in this video:

No need for needles – David Fernandez Rivas from University of Twente on Vimeo.

Proposal abstract

BuBble Gun features a novel injection method using confined cavitation induced by continuous wave lasers, to create fast liquid jets that penetrate target substrates. The accurate delivery of volumes into complex substrates, e.g. human tissue, is limited by: the need to reach specific depths with energy efficient methods, the break-up of jets that impedes control over the delivered dose, and liquid splash-back after bouncing on the substrate that causes cross-contamination. The main objective of BuBble Gun is to gain new scientific knowledge to overcome these challenges.

My overarching goal is to develop a clear picture of the energy partition initiated with the creation of bubbles, converted by the tuned rheology of jets, and ending with jet penetration into soft substrates. This fundamental knowledge will be applied to achieve a major breakthrough in liquid jet injection, by: i) Controlling cavitation within microfluidic confinement, ii) Tuning the rheology of jets emerging from confined cavitation, and iii) Deriving the relationships between fluid dynamics and material properties governing jet injection into complex soft substrates, in particular human skin.

Ultra-high-speed imaging and advanced bioengineering techniques will allow studying phenomena below the microsecond and micrometer scales. Jets will be tuned with biocompatible additives to ensure cohesion, before injecting them in-vitro and ex-vivo skin. Numerical models will assist disentangling the influence of geometry and material properties.

I expect to unveil new knowledge at the intersection of microfluidics, physics, and bioengineering, towards a new understanding of cavitation, jetting rheology, and injection phenomena. With this understanding, my team will develop a portable energy efficient platform for future innovations. For example, coating modifications and additive manufacturing, where jetting of a wide range of liquids is crucial, and particularly for needle-free drug delivery in medicine.

Energy cascade with approximate timescales for each phenomenon.