"3D Necroprinting" Turns Mosquitos Proboscides Into Ultra-Fine Nozzles for Tiny Prints

Researchers have turned to necromancy, or "necroprinting," to deliver a new, ultra-fine nozzle for 3D printing of objects as small as 20µm in width — harvesting the proboscides of mosquitos to deliver a resolution man-made hardware can't match.

"Nature has long inspired engineering innovations. Recent advances in biohybrid research have taken this inspiration further by directly integrating biotic materials into engineered systems," the researchers explain of their project. "Here we report '3D necroprinting,' a biohybrid manufacturing technique that repurposes female mosquito proboscides as high-resolution 3D printing nozzles."

In fused filament fabrication (FFF/FDM), extruders push material through a nozzle to deposit it on the print surface under computer control — then raise the nozzle up to print the next layer. Commercial 3D printers are already capable of printing at a surprisingly high resolution, but once you get into the micro scale things hit a brick wall: even the finest of man-made nozzles can't get print below around 40µm in width.

The team's bio-nozzle, harvested from female mosquitos and more usually found piercing skin to suck blood, breaks through this barrier, delivering fine-line widths down to 20µm while withstanding pressures of up to 60kPa. "By introducing biotic materials as viable substitutes to complex engineered components," the researchers say, "this work paves the way for sustainable and innovative solutions in advanced manufacturing and microengineering."

To prove the concept, the team printed range of different materials — including a tiny decorative maple leaf, a honeycomb structure, and, in a demonstration of the sort of real-world applications envisioned for the technology, bio-scaffolds designed to encapsulate cancer and red blood cells.

"This work validated the feasibility of using a laboratory-grown, uninfected female mosquito proboscis as a dispense tip for high-resolution printing, showcasing its potential as a low-cost, environmentally sustainable alternative to conventional metal and plastic dispense tips," the team concludes. "Beyond the female mosquito proboscis, other biological micro dispense tips could be explored and raised in a laboratory setting to meet diverse engineering needs in a disease-free capacity, broadening the applicability of biohybrid manufacturing: aphid proboscides offer an internal diameter of <1µm."

The team's work has been published in the journal Science Advances under open-access terms.