Photolithographic method used to control the formation of DNA hydrogels

MAR 20, 2020

Method of controlling the shape of DNA hydrogels at a micrometer scale using light irradiation doesn’t require radical polymerization.

Savannah Mandel

DOI: 10.1063/10.0000959

Photolithographic method used to control the formation of DNA hydrogels internal name — Photolithographic method used to control the formation of DNA hydrogels lead image

DNA hydrogels, soft materials created from water and self-assembled DNA nanostructures, can be programmed for a wide variety of biomedical applications, such as tissue engineering and drug delivery.

Kasahara et al. used selective light exposure to shape DNA hydrogels into micropatterns. This photolithographic method allows for micrometer-scale control through light-activated self-assembly of the hydrogels.

“We developed light-responsive cross-linking DNA molecule in order to achieve perform the self-assemble of DNA nanostructure in a light-position-selective manner. This unique technique realized the micropatterning of DNA hydrogels with light irradiation,” said author Masahiro Takinoue.

The authors modelled the cross-linker DNA into a hairpin shape, a mechanism which allowed them to form DNA hydrogels only at the UV-exposed area in the DNA solution. They used light irradiation through a photomask to control the shape and microstructure of the hydrogels. Unlike previous methods of controlling hydrogels, this method does not require the use of radical polymerizations.

“Based on our method, functional micropatterned DNA gels can be created and will be applied to the functional microrobots in future. We will be able to construct microrobots or micromachines, which are compatible with biological systems, such as cells,” said Takinoue. “The function of the microrobots/micromachines can be designed with DNA base sequences.”

Currently, the DNA hydrogels can form micropatterns with around 500 micrometer precision. In the future, the authors intend on improving this to just several micrometers by managing the hybridization reaction rate and the diffusion rate of DNA molecules.

Source: “Photolithographic shape control of DNA hydrogels by photo-activated self-assembly of DNA nanostructures,” by Yu Kasahara, Yusuke Sato, Marcos K. Masukawa, Yukiko Okuda, and Masahiro Takinoue. APL Bioengineering (2020). The article can be accessed at https://doi.org/10.1063/1.5132929 .