Fabrication and characterization of photoluminescent silicon nanoparticles for drug delivery applications.

Photoluminescent silicon nanoparticles containing camptothecin (CPT) were fabricated by using a CPT-derivatized porous silicon (PSi). PSi samples displaying red photoluminescence (PL) were prepared by an electrochemical etch of n-type silicon under the illumination with a 300 W tungsten filament bulb for the duration of etch. For the drug-derivatized PSi, luminescent PSi was oxidized and derivatized with CPT. Silicon nanoparticles containing CPT were obtained by fracturing of luminescent PSi with ultrasono-method. Optical characteristic of drug-derivatized silicon particles were investigated in aqueous buffer solution. The release of CPT was measured by UV-vis spectrometer. The intensity of fluorescence of the silicon nanoparticles was measured with a drug release. The concentration of released drug exhibited non-linear relationship with a release time.