MIT researchers printed 16 triaxial electrospray emitters in a square centimeter, collapsing a days long semiconductor process into an hours long benchtop job that no longer requires cleanroom fabrication.
MIT researchers have printed a centimeter-scale array of 16 triaxial electrospray emitters, devices that stack three immiscible liquids into layered microdroplets in a single step, a process that previously required microfabrication rigs built over days by specialists. The work, reported this week in MIT News and published in the journal Virtual and Physical Prototyping, points to a shift in who can make these particles: layered fabrication, the kind that underpins time-release medicines, self-healing materials, and biosensors that read multiple chemical markers at once, no longer requires semiconductor cleanroom access.
The emitter is small enough to sit on a U.S. penny and is built in one step using vat photopolymerization, a light-cured resin process with 25-micrometer layer resolution. The team, led by principal research scientist Luis Fernando Velásquez-García of MIT's Microsystems Technology Laboratories, designed helical internal microchannels that feed three liquids uniformly to all 16 nozzles. Without that geometry, the flow becomes uneven and the layered droplets fail to form.
The MIT press release frames the advance as a democratization of layered-particle manufacturing. The technically accurate version is narrower. The team has demonstrated a 16-nozzle array at lab scale, with model fluids, and the paper notes that no prior open-literature example of a miniaturized triaxial electrospray array existed. No throughput or cost-per-particle numbers are reported against the cleanroom baseline the device is implicitly meant to replace, so claims that it is "cheaper" or "faster" read as a directional shift rather than a benchmarked result.
The mechanism behind the three-layer droplets is the central technical finding. The viscosity of the middle liquid, more than voltage or flow rate, stabilizes the inner and outer layers during particle formation. Once that relationship is set, layer thicknesses can be tuned by adjusting flow rates and voltage, giving a formulator control over release timing. A particle designed for oral drug delivery, for instance, can carry an outer layer that erodes in the stomach, a middle layer that controls the rate, and a core that releases its payload in a specific region of the intestine. The same geometry applies to self-healing composites, where one liquid carries a healing agent sealed inside a brittle shell, and to single-droplet biosensors that detect three chemical markers at once.
Funding came from the Tecnológico de Monterrey–MIT Nanotechnology Program, and lead author Bryan Ivan Quintanar-Abarca is based at Tecnológico de Monterrey in Mexico, a reminder that this is a cross-border collaboration rather than a single-lab story.
What to watch next: whether the same print-and-use geometry holds up with real pharmaceutical formulations, whether larger arrays (hundreds of nozzles) scale the way the 16-nozzle geometry suggests they might, and whether the cost and time claims survive comparison to a real cleanroom-built emitter in a head-to-head benchmark. None of those answers are in the current paper. The fabrication capability is demonstrated; clinical and pharmaceutical-manufacturing scale remains an open question.