Microfluidic jet impact: spreading, splashing, soft substrate deformation and injection

Diana Laura van der Ven, Davide Morrone, Miguel Angel Quetzeri Santiago*, David Fernández Rivas

*Corresponding author for this work

Research output: Contribution to journalArticleAcademicpeer-review

6 Citations (Scopus)
38 Downloads (Pure)


Hypothesis: Needle-free injections using microfluidic jets could be optimized by reducing splashing and controlling injection depth. However, this is impeded by an incomplete understanding on how jet characteristics influence impact outcome. We hypothesise that exploring the relation between microfluidic jet characteristics and substrate shear modulus on impact behavior will assist in predicting and giving insights on the impact outcome on skin and injection endpoints. Experiments: To do so, a setup using microfluidic chips, at varying laser powers and stand-off distances, was used to create thermocavitation generated microfluidic jets with ranging characteristics (velocity: 7–77 m/s, diameter: 35–120 μm, Weber-number: 40–4000), which were impacted on substrates with different shear modulus. Findings: Seven impact regimes were found, depending on jet Weber-number and substrate shear modulus, and we identified three thresholds: i) spreading/splashing threshold, ii) dimple formation threshold, and iii) plastic/elastic deformation threshold. The regimes show similarity to skin impact, although the opacity of skin complicated determining the threshold values. Additionally, we found that jet velocity has a higher predictive value for injection depth compared to the Weber-number, and consequently, the jet-diameter. Our findings provide fundamental knowledge on the interaction between microfluidic jets and substrates, and are relevant for optimizing needle-free injections.

Original languageEnglish
Pages (from-to)549-558
Number of pages10
JournalJournal of colloid and interface science
Early online date9 Jan 2023
Publication statusPublished - 15 Apr 2023


  • UT-Hybrid-D


Dive into the research topics of 'Microfluidic jet impact: spreading, splashing, soft substrate deformation and injection'. Together they form a unique fingerprint.

Cite this