Laser-mediated gene transfection has received much attention as a new method for targeted gene therapy because of the high controllability of
laser energy and direction. In this report, we describe a combination
laser-
microbubble system that enables membrane-impermeable molecules to penetrate cell membranes. The main theories we apply are optical breakdown and photoacoustic generation, which are induced by
laser irradiation. Firstly, different types of
laser light (Ar-green,
Novus Varia poly-wavelength and
Nd:YAG laser) were adopted to blast
liposome microbubble contrast medium; subsequently, the
Nd:YAG laser (1064 nm, 4 ns), which could successfully blast
microbubbles, and ultrasound were used in combination to irradiate a mixture of
liposome microbubbles and
retinoblastoma (Rb) cells. After irradiation, membrane permeability was evaluated by flow cytometric assay using
propidium iodide (PI) and
fluorescein diacetate (FDA). The proportion of permeabilized resealed cells was affected by changes in the light energy. All of the
Nd:YAG laser, Nd:YAG combination
laser-
microbubble and combination ultrasound-
microbubble systems were able to permeabilize the Rb cells. These results suggest that this combination
laser-
microbubble system is a new means of delivering exogenous materials into living cells.