Porous Silicon as a Nanomaterial for Disperse Transport Systems of Targeted Drug Delivery to the Inner Ear

The samples of porous silicon (por-Si) particles in three size ranges (60–80, 250–300, and 500–600 nm) are obtained by electrochemical anodic etching of single-crystal silicon in an electrolyte based on an HF solution, followed by a change in the modes of ultrasonic treatment and homogenization. A complex characterization of particles was carried out by scanning electron microscopy, photon cross-correlation spectroscopy, and X-ray photoelectron spectroscopy. In vitro biocompatibility models using unicellular organisms of infusoria Paramecium caudatum Keln are applied to demonstrate the low toxicity of the samples at concentrations used for intravenous administration. The systemic in vivo biodistribution was studied for the por-Si 60–80 nm sample using adult Wistar rats. Introduced nanoobjects are found in the liver and heart tissues without significant changes in shape or size and predominantly in the oxidized state. Possibilities of using por-Si samples as matrices for transporting pharmaceuticals with intravenous administration are studied by assessing the intensity of the ototropic effect of gentamicin. An objective audiologic method for studying the amplitude of otoacoustic emission revealed the largest otodepressive effect of gentamicin when submicrometer-sized por-Si particles (500–600 nm) was used as a disperse system for drug delivery. Thus, modifications of the conditions for the synthesis of por-Si nanoparticles are promising directions in obtaining physicochemical parameters of transport particles that are optimal for specific tasks of targeted drug delivery.