Biocompatible Collagen Paramagnetic Scaffold for Controlled Drug Release

Abstract

A porous collagen-based hydrogel scaffold was prepared in the presence of iron oxide nanoparticles (NPs) and was characterized by means of infrared spectroscopy and scanning electron microscopy. The hybrid scaffold was then loaded with fluorescein sodium salt as a model compound. The release of the hydrosoluble species was triggered and accurately controlled by the application of an external magnetic field, as monitored by fluorescence spectroscopy. The biocompatibility of the proposed matrix was also tested by the MTT assay performed on 3T3 cells. Cell viability was only slightly reduced when the cells were incubated in the presence of the collagen-NP hydrogel, compared to controls. The economicity of the chemical protocol used to obtain the paramagnetic scaffolds as well as their biocompatibility and the safety of the external trigger needed to induce the drug release suggest the proposed collagen paramagnetic matrices for a number of applications including tissue engeneering and drug delivery.

On‐Demand Release of Hydrosoluble Drugs from a Paramagnetic Porous Collagen‐Based Scaffold

“…In Figure the C 1s peaks are reported. The first impact from the nanoparticles is a decrease in the amount of carbon, similar to the case of the collagen with the IO NPs . The deconvolution of this peak gives four Gaussian features, which belong to carbon atoms from different groups .…”

“…The presence of an increased number carboxylic groups brings about more binding groups for the surface of the TiO 2 . It is worth highlighting that the naked paramagnetic nanoparticles were not able to covalently interact with the protein, but the titanium dioxide shell works as cross‐linker.…”

“…Two collagen gel samples were prepared according to the procedure reported in a previous work, with some modifications: a porous collagen gel and a gel containing IO@TiO 2 NS. For the porous collagen scaffold preparation, in particular, the dry collagen flakes were dispersed in an acetic acid solution (0.5 m ) to prepare a 1 % (w/v) suspension.…”

“…For the preparation of the collagen scaffold containing the nanostructures, naked iron oxide (IO) nanoparticles (NPs) were prepared as already reported . The TiO 2 capping of the surface of the NPs was carried out by applying a sol‐gel process .…”

“…The biocompatibility of the collagen‐based scaffolds was evaluated on fibroblast cell line 3T3 and MTT assay was performed as reported previously . Briefly, cells were seeded at a density of 5×10 4 /well in a 24‐well plate containing 1 mL of culture medium (Dulbecco's modified Eagle's medium, DMEM) supplemented with 10 % (v/v), foetal bovine serum (FBS), 1 % penicillin/streptomycin, and 1 m m l ‐glutamine and cultured at 37 °C in 5 % CO 2 humidified atmosphere overnight.…”