The resulting effects of the interaction between nanoparticles and laser irradiation are a current matter in research.
Depending on the laser parameters as well as the particles properties several effects may occur e.g. bubble formation,
melting, fragmentation or an optical breakdown at the surface of the nanoparticle. Besides the investigations of these
effects, we employed them to perforate the membrane of different cell lines and investigated nanoparticle mediated laser
cell perforation as an alternative optical transfection method. Therefore, the gold nanoparticles (GNP) of different shapes
were applied. Furthermore, we varied the methods for attaching GNP to the membrane, i.e. co-incubation of pure gold
nanoparticles and bioconjugation of the surface of GNP. The optimal incubation time and the location of the GNP at the
cell membrane were evaluated by multiphoton microscopy. If these GNP loaded cells are irradiated with a fs laser beam,
small areas of the membrane can be perforated. Following, extra cellular molecules such as membrane impermeable dyes
or foreign DNA (GFP vectors) are able to diffuse through the perforated area into the treated cells. We studied the
dependence of the laser fluence, GNP concentration, GNP size and shape for successful nanoparticle mediated laser cell
perforation. Due to a weak focusing of the laser beam a gentle cell treatment with high cell viabilities and high
perforation efficiencies can be achieved. A further advantage of this perforation technique is the high number of cells
that can be treated simultaneously. Additionally, we show applications of this method to primary and stem cells.