Researchers have synthesized different DNA-based microstructures by dissolving DNA from salmon testes in a non-toxic and biocompatible solvent1. These microstructures can ferry drugs and genes to target tissues including tumour cells.

The researchers dissolved salmon testes DNA in a solvent made by heating a mixture of choline chloride and ethylene glycol in the presence of an inert gas. By adding an acid or base to the DNA-containing solvent, they prepared three DNA-based microstructures: a pH-reversible DNA ion gel, a spheroidal micro-sized DNA, and a pH-responsive DNA microhydrogel.

The scientists then explored the drug- and gene-delivery potential of the microstructures at pH levels that prevail in physiological environments. They found that the microstructures had low negative zeta potentials, which was very encouraging as previous studies had shown that negatively charged nanoparticles selectively bind to tumour cells, sparing healthy cells.

The researchers say that negative potentials prevent the microstructures being rapidly eliminated from the blood stream, increasing their accumulation at the tumour sites and thereby enhancing their drug-delivery potential. In addition, they found that the microstructures were stable for more than a week in colloidal suspensions.

“The DNA-based microstructures may find applications in targeted gene or drug delivery and electrochemistry,” says lead researcher Kamalesh Prasad.