Researchers at Pennsylvania State University have proven that nano-sized calcium phosphate delivers drugs safely and effectively to skin. The researchers reported these findings in Nano Letters. The calcium phosphate particles, ranging in size from 20 to 50 nanometers, successfully enter cells and dissolve harmlessly, releasing their cargo of drugs or dye.
Peter Butler, associate professor of bioengineering, and his students conducted time correlated single photon counting, where they used high-speed lasers to measure the size of fluorescent dye-containing particles from their diffusion in solution. Through this method, the group was able to measure the size of the particles and their dispersion in a solution that modeled blood.
Instead of a neutral pH, the research team made the solution more acidic to mimic the environment around tumors. A lower pH caused the calcium phosphate particle to dissolve. The research team, therefore, finds that the pH change can be used to release the drug encapsulated in the nanoparticle.
The research was done to target cancer therapy; however it may be able to treat vascular disease. According to the team, calcium phosphate is a safe, naturally occurring mineral that already is present in substantial amounts in the bloodstream. They find that the nanoparticles will need less of a drug for the same efficacy. The research was supported by National Science Foundation, NASA, Keystone Nano Inc. and NIH-NHLBI.