Parameters affecting intracellular delivery of molecules using laser-activated carbon nanoparticles

Previous studies showed that carbon nanoparticles exposed to nanosecond laser pulses cause intracellular uptake of molecules. In this study, prostate cancer cells incubated with carbon-black (CB) nanoparticles and fluorescent marker compounds were exposed to 10ns laser pulses at 1064nm wavelength, after which intracellular uptake was measured by flow cytometry. Calcein and dextran (150kDa) were delivered into >50% of cells, whereas larger dextrans (≤2000kDa) were taken up by ~10% of cells. Under all conditions studied, cell viability loss was minimal. Uptake also increased with increasing laser power, increasing CB nanoparticle concentration, increasing CB nanoparticle size and decreasing laser wavelength. CB nanoparticles enabled uptake better than gold nanoparticles or multi-walled carbon nanotubes under the conditions studied. Proof-of-principle experiments showed intracellular uptake by cells in vivo. We conclude that intracellular uptake of molecules using laser-activated CB nanoparticles provides a promising approach to deliver molecules into cells.

Delivery of drugs using nanoparticles as carriers is promising. The authors in this study investigated the use of laser-activated carbon nanoparticles to increase the cellular uptake of payloads in various parameters. The positive data generated should provide further platform for a new approach for intracellular delivery of molecules.