Fluorescent molecules are attached to the hydrogel, resulting in a microscopic 3D pattern.
Two research teams from the Vienna University of Technology collaborated to develop 3D-photografting. With laser beams, molecules are affixed at exactly the right position in a three dimensional material to grow biological tissue or to create micro sensors.
When biological tissue is grown, this method can allow the positioning of chemical signals, telling living cells where to attach. The new technique also holds promise for sensor technology: A tiny three dimensional “lab on a chip” could be created, in which accurately positioned molecules react with substances from the environment.
There are many ways to create three dimensional objects on a micrometer scale. But how can the chemical properties of a material be tuned at micrometer precision? Scientists at the Vienna University of Technology developed a method to attach molecules at exactly the right place.
The scientists start with a hydrogel – a material made of macromolecules arranged in a loose meshwork. Between those molecules, large pores remain, through which other molecules or even cells can migrate. Specially selected molecules are introduced into the hydrogel meshwork, and then precise locations are irradiated with a laser beam, which breaks a photochemical labile bond.
“Much like an artist, placing colors at certain points of the canvas, we can place molecules in the hydrogel – but in three dimensions and with high precision,” says Aleksandr Ovsianikov, an participant on the research team.