“To integrate the proboscis, we first removed it from an already euthanized mosquito under a microscope,” explains Cao. The proboscis/nozzle was then aligned with the outlet of the plastic tip. Finally, the proboscis and tip were glued together with UV-curable resin.
The Necroprinter achieved resolutions ranging from 18 to 22 microns, which is half that of printers using the smallest commercially available metal dispensing tips. Early printing tests included 600-micron honeycomb structures, microscale maple leaf, and cell scaffolds.
But there were still areas in which man-made technology managed to surpass Mother Nature.
Glass and pressure
The first problem with mosquito nozzles was their relatively low resistance to internal pressure. “It was impressive, but still too small for a high-viscosity ink,” Cao said.
This ink, which is more like a paste than a regular liquid, holds its shape better, resulting in more geometrically accurate designs that don't settle or bleed under their own weight. This was a problem that Cao's test prints faced to some extent.
But this was not the only area where man-made technology managed to surpass nature. While mosquito repellent tips can outperform plastic or metal alternatives in accuracy, they cannot beat glass dispensing tips, which can print lines less than one micron in diameter and withstand significantly higher pressures.
However, researchers already have some ideas about how to bridge at least part of this gap. “One possible solution is to use the mosquito's proboscis as the core and cover it with ceramic layers to provide much greater strength,” Cao said. And if the pressure problem can be solved, a resolution of 18–22 microns will be sufficient for many applications.
Cao believes that in the future such printers could be used to print scaffolds of living cells or microscopic electronic components. The idea is to replace expensive traditional 3D printing nozzles with more affordable organic alternatives. According to him, the key advantages of mosquito repellents are low cost and ubiquity.
Mosquitoes live almost everywhere on Earth and are easy to breed. The team estimates that organic 3D-printed baits made from mosquito proboscis should cost about 80 cents; alternatives made of glass and metal, according to the researchers in the article, cost between 32 and 100 times more.
“We have already started doing more research on the mosquitoes themselves and hope to develop more engineering solutions not only to use their dead bodies, but also to solve the practical problems they cause,” Cao said.
Achievements of science, 2025 DOI: 10.1126/sciadv.adw9953
