Exploring the ultrashort pulse laser parameter space for membrane permeabilisation in mammalian cells.

The use of ultrashort femtosecond pulsed lasers to effect membrane permeabilisation and initiate both optoinjection and transfection of cells has recently seen immense interest. We investigate femtosecond laser-induced membrane permeabilisation in mammalian cells as a function of pulse duration, pulse energy and number of pulses, by quantifying the efficiency of optoinjection for these parameters. Depending on pulse duration and pulse energy we identify two distinct membrane permeabilisation regimes.

Optical injection of mammalian cells using a microfluidic platform.

The use of a focused laser beam to create a sub-micron hole in the plasma membrane of a cell (photoporation), for the selective introduction of membrane impermeable substances (optical injection) including nucleic acids (optical transfection), is a powerful technique most commonly applied to treat single cells. However, particularly for femtosecond photoporation, these studies have been limited to low throughput, small-scale studies, because they require sequential dosing of individual cells. Herein, we describe a microfluidic photoporation system for increased throughput and automated optical injection of cells.

Enhanced operation of femtosecond lasers and applications in cell transfection.

In this work we present a review and discussion on the enhancement of femtosecond (fs) lasers for use within biophotonics with a particular focus on their use in optical transfection techniques. We describe the broad range of source options now available for the generation of femtosecond pulses before briefly reviewing the application of fs laser in optical transfection studies. We show that major performance enhancements may be obtained by optimising the spatial and temporal performance of the laser source before considering possible future directions in this field.