DNA Nanostructures Stabilized with Buffers in Low Magnesium Conditions


DNA structure/ Photo By Sergey Nivens via 123RF


A new study showed a promising method on how to balance the resilience of DNA origami in very low magnesium concentrations. Previous studies implied that the nanostructures require high levels of magnesium to last longer, but researchers at Aalto University found a way to circumvent that.

In the study, the research group analyzed how to stabilize DNA that underwent the DNA origami technique, a technique of DNA folding to create specific 2D and 3D shapes at the nanoscale. Typically, folded DNA requires a large amount of magnesium to remain stable, but that amount is very high compared to the magnesium content in the human body.

"Conventional DNA origami assembly requires levels of magnesium easily 10-30 times as high as those in normal physiological conditions. With our method, we can go below one-thousandth of the minimum magnesium concentration previously reported," explained Professor Veikko Linko at Aalto University.

The key to their analysis was the application of buffer exchange to sustain the stability of folder DNA. They used a common element of buffer solutions called Tris and combined it with pure water to eliminate the free ions of magnesium from folded DNA. Their findings also showed that buffers based on phosphate have an adequate concentration of potassium or sodium that could keep folded DNA stable.

When they tested it the buffer exchange with DNA nanostructures, the tiny materials demonstrated structural integrity and lasted for an extended period of time, compared to the traditional magnesium-sustained folded DNA. The nanostructures can be stored in low magnesium environments for weeks or months without showing signs of structural damages.

“These findings might pave the way for a plethora of biomedical uses that were previously thought impossible, as for example fluorophores and many enzymes are sensitive to magnesium levels," added Prof. Linko.