The ability to transfer a gene or DNA sequence from one animal into the genome of another plays a critical role in a wide range of medical research—including cancer, Alzheimer’s disease, and diabetes. But the traditional method of transferring genetic material into a new cell, called "microinjection," has a serious downside. It involves using a small glass pipette to pump a solution containing DNA into the nucleus of an egg cell, but the extra fluid can cause the cell to swell and destroy it -- resulting in a 25 to 40 percent cell death rate.

Source: MEMS nanoinjector for genetic modification of cells