Scientists have created an ultra-precise way to inject DNA into a cell.

Genetic engineering is used for a large number of applications, but the methods are extremely shaky, an Optical Society press release reported.

The current methods lack precision in the DNA insertion, and often cause researchers to "burn through" several cells before finding one that will take.

A South Korean research team found a way to accomplish genetic engineering more efficiently using "two high-tech laboratory techniques."

The process allows researchers to "poke holes on the surface of a single cell with a high-powered 'femtosecond' laser and then gently tug a piece of DNA through it using 'optical tweezers,' which draw on the electromagnetic field of another laser," the press release stated.

"What is magical is that all this happens for one cell," Yong-Gu Lee, an associate professor in the School of Mechatronics at the Gwangju Institute of Science and Technology in South Korea, who participated in the study, said. "Until today, gene transfection has been performed on a large quantity of agglomerate cells and the outcome has been observed as a statistical average and no observations have been made on individual cells."

Researchers often use "gene guns" to shoot the DNA into large colonies of cells. Another known method is to use layers to puncture a cells membrane, and then place the cells in a "plasmid soup," so the DNA can seep in.

Both of these methods have seen successful, but the researcher has very little control over the outcome. Cells can be damaged in the clumsy process.

This new, safer method "used optical tweezers, which essentially tweaks a laser beam whose electromagnetic field can grab hold of and transport a plasmid-coated particle."

A laser pulse creates a small hole in the cell's membrane, and the tweezers push the DNA through. The process allowed the scientists to transfect the cell "like a golfer sinking an easy putt."

To test their new technology the team "infected" a cell with a gene carrying a fluorescent green protein. If the process was successful the cell would look green under a microscope. One in six cells successfully became transfected. While this statistic is lower than some other methods, it uses significantly less cells.

The study was published in Biomedical Optics Express.