Permeability of Matrigel to magnetic nanoparticles

Abstract

Up to day, the study of in-vitro cellular uptake of magnetic nanoparticles is performed in cells growing in two-dimensional (2D) cultures, i.e., cell monolayers on a Petri dish. However, 2D culture conditions do not represent the more intricate environment of the in-vivo cells. At present, 3D cell culture reflects better an environment in which cells grow interacting with their polarized growth and represent the in-vivo situation more accurately. Matrigel is a gelatinous protein mixture that resembles the complex extracellular matrix found in tissues and is used as a substrate for 3D culture. Then, previous to the investigation of nanoparticles cellular uptake in 3D cells, it is necessary to understand how the nanoparticles interact with the extracellular environment. In this work, we investigate the permeability of Matrigel to the magnetic nanoparticles. For this purpose, an aliquot of magnetic colloid is deposited on the Matrigel surface and the colloidal diffusion is investigated by Confocal Fluorescence Microscopy for >as-deposited> at 24, 48 and 72 h after colloid deposit. By measuring the temporal evolution of the depth length of the colloid it is possible to analyse the permeability of the Matrigel to the magnetic nanoparticles. The permeability of the Matrigel to the magnetic nanoparticles is investigated also as a function of the nanoparticle size.