A laser-based technique permits the delivery of energy-generating organelles called mitochondria into single mammalian cells, where they can restore metabolic activities.
Mitochondria have their own DNA, which can cause disease if mutated, and researchers have been looking for ways to isolate the organelles, correct genetic defects and return the mitochondria to cells. Pei-Yu Chiou and Michael Teitell at the University of California, Los Angeles, and their colleagues coated a micropipette tip with a 100-nanometre-thick film of light-absorbing titanium and lightly touched it to a cell membrane. A laser pulse heated the tip, causing a bubble to quickly form and collapse in the cell's culture medium. The bubble's expansion punctured the membrane, creating an opening large enough for the delivery of mitochondria.
The technique's 2% efficiency rate is higher than that of other methods, and the team is now working to increase throughput.