Intracellular Drug Delivery Using Laser Activated Carbon Nanoparticles

One of the most pressing matters in the field of pharmaceuticals today deals not with the development of the drug itself, but rather with its method of delivery. A new physical method for intracellular drug delivery proposes injecting carbon nanoparticles into the body along with the drug. Infrared laser pulses can then be used to interact with the carbon nanoparticles and generate a photoacoustic pressure wave that increases cell permeability. The objective of this research project was to manipulate the parameters of in vitro DU145 cell laser exposure experiments to improve the process by inducing an increase in cell uptake and cell viability.

The results from a series of infrared laser exposure experiments indicate that optimum cell uptake occurs at laser fluences above 50 mJ/cm² and that increasing the fluence even to its limit will not adversely affect the viability of the cells. Results from further experiments show that changing the molecular weight of the drug had no effect on cell uptake or cell viability; that using a cuvette of varying size and thickness does not significantly affect the laser absorption of the drug in question; and that cell uptake increases when a surfactant is added to the drug and carbon solution. Based on these experiments, we have increased our ability to optimize intracellular drug delivery using laser activated carbon nanoparticles. This research project is significant because it could be a new and innovative way for drugs to be delivered more efficiently and effectively to intracellular targets.