Iron/Magnetite Nanoparticles as Magnetic Delivery Systems for Antitumor Drugs.

In this study we investigate on the possible use of a new kind of magnetic nanostructures as drug delivery systems for anticancer drugs. The starting particles are formed by an inner core of iron, coated by magnetite as a stabilizing, magnetic layer. These units are further coated by a poly(ethylenglycol) (PEG) layer to make them less prone to the attack by macrophages and to favour longer stays in the blood stream.

Functionalized magnetic nanoparticles as vehicles for the delivery of the antitumor drug gemcitabine to tumor cells. Physicochemical in vitro evaluation.

Gemcitabine is a chemotherapy drug used in different carcinomas, although because it displays a short biological half-life, its plasmatic levels can quickly drop below the effective threshold. Nanoparticle-based drug delivery systems can provide an alternative approach for regulating the bioavailability of this and most other anticancer drugs. In this work we describe a new model of composite nanoparticles consisting of a core of magnetite nanoparticles, coated with successive layers of high molecular weight poly(acrylic acid) and chitosan, and a final layer of folic acid.

Transparency in a fibrin and fibrin-agarose corneal stroma substitute generated by tissue engineering.

Purpose: To examine the transparency characteristics at different times of development in the culture of 2 different types of human corneal stroma substitutes generated by tissue engineering using human fibrin or human fibrin and 0.1% agarose, with human keratocytes entrapped within.

Methods: The transparency of these artificial corneal stromas was analyzed after 1, 7, 14, 21, and 28 days of development in culture by determining the scattering and absorption coefficients from the spectral reflectance data of each sample using the Kubelka-Munk equations.