Folic Acid Delivery Device based on Porous Silicon Nanoparticles Synthesized by Electrochemical Etching

Folic acid insufficiency has long been related to the occurrence of various diseases. However, the loss of integrity of folic acid has led to the investigation of strategies to improve the vitamin stability and controlled release. Porous silicon nanoparticle is an attractive inorganic material for drug delivery applications due to its biocompatibility and tunable degradation behavior. The aim of this work is to produce porous silicon nanoparticles with suitable dimensions for loading folic acid. Porous silicon was fabricated by anodic electrochemical etching in a Teflon cell containing a 1: 4 (v/v) solution of 49% aqueous HF in ethanol. Pores between 15 and 20 nm in diameter were obtained and the highly degradable porous silicon was stabilized to SiO2 structures by thermal oxidation. Folic acid was loaded into these structures by simple adsorption and the release was examined by UV absorption spectroscopy. The surface morphology of porous silicon delivery device in each stage of the fabrication was characterized by FE-SEM, X-ray spectrometer, FTIR, and XRD and the drug loading confirmed based on the comparison with pure folic acid spectra. pSi nanoparticles showed optimal folic acid delivery capabilities (60 % released after 6 h) and due to its simple fabrication method and its intrinsic optical properties have the potential to be used as a diagnostic and therapeutic point of care tool.