Therapeutic Applications of Lasers

A major focus of therapeutic application is to investigate the cellular effects of localized energy deposition into endogenous or exogenous chromophores.

Micro- and Nano--Particle Assisted Selective Cell Targeting
By labeling cell population of interest with highly absorbing micro- or nano-particles, spatial confinement of laser energy deposition has been demonstrated. This technique allows us to selectively destroy cells and transiently permeabilize cell membrane to allow delivery of molecules (drugs, genes, etc.)

Selective Cell Targeting for the Treatment of Retinal Diseases
The presence of strongly absorbing microparticles (melanosomes) in the retinal pigment epithelium (RPE) behind the photoreceptors, enables us to develop new therapeutic strategies to selectively treat the RPE cells in certain retinal diseases (such as diabetic macular edema) without damaging the photoreceptors. We have developed a laser scanner that rapidly scans the small spot of a continuous wave laser across the retina so as to produce microsecond-short irradiation at each exposed RPE cell. We have shown successfully, that individual RPE cells can be damaged.

Calcein stained explants of bovine RPE, before (left) and after irradiation (right) with a pre-defined scan pattern of cw green laser (middle). After irradiation damaged cells loose the fluorescence and turn dark. Alternating lines of dead and surviving cells that resemble the scan pattern suggest selectivity. (Alt et al. J. Biomedical Optics, in press)

Research Projects

Advanced Microscopy
Therapeutic Applications of Lasers