Microencapsulation of Erlotinib and Nanomagnetite Supported in Chitosan as Potential Oncologic Carrier.

Microcapsules (MC) based on chitosan (CH) and including nano-magnetite and erlotinib were synthesized. The microparticles were characterized by SEM, FT-IR and TGA. The percentage of encapsulation was determined, as well as its microbiological activity. Finally, the effectiveness of the formulation was evaluated in terms of cell viability and/or toxicity when compared with the reference drug. The formulation used to prepare the microcapsules showed some bacteriostatic properties. The characterization of microcapsules exhibited amorphous spherical shape and average size of 1.29, 1.58 and 1.62 mm for chitosan, chitosan + nanomagnetite and chitosan + nanomagnetite + erlotinib, respectively. The infrared spectra showed characteristic bands of the erlotinib and magnetite, confirming its internalization. The thermogravimetric analyzes indicated that the materials do not undergo changes at optimum working temperatures. The HPLC analysis showed a 52% of encapsulation. Finally, the formulation probed had lower effectiveness and less cytotoxicity, than the drug without encapsulating "in vitro" studies. For that reason several assays are in progress.

Influence of Granulometry on Thermal and Mechanical Properties of Cement Mortars Containing Expanded Perlite as a Lightweight Aggregate.

This research aims at clarifying the influence of the granulometry of expanded perlite, on the thermal conductivity, structural strength, density, and water absorption of lightweight mortars. Three original perlite gradations have been obtained and three pairs of twin test mortars have been tested with those gradations. SEM tests have also been run to clarify the interaction, at a microscopic level, between the expanded perlite and the cement grouting. The results indicate that the mere manipulation of the granulometry may have a considerable and very beneficial effect on the mixture's properties, such as thermal conductivity and water absorption.

Chitosan doped with nanoparticles of copper, nickel and cobalt.

Metal colloids in 2 propanol using nanoparticles (NPs) of copper, nickel and cobalt were prepared by Chemical Liquid Deposition (CLD) method. The resulting colloidal dispersions were characterized by Transmission Electron Microscopy (TEM). The colloids were supported in chitosan. Then, microbiological assays were performed using E. coli and S. aureus in order to determine the bactericide/bacteriostatic activity of nanoparticles (NPs) trapped or chelated with chitosan. Finally, the toxicity of the metal colloids Cu, Ni and Co was tested. Bio-assays were conducted in three different animal species. First of all on earth warms (Eisenia foetida) to evaluate the toxicity and the biocompatibility of chitosan in lactic acid (1% and 0.5%). Secondly bio-assay done in fishes (rainbow trout), the liver toxicity of NPs in vivo was evaluated. Finally, a bio-assay was conducted in Sprange-Dawley rats of 100g weight, which were injected intraperitoneally with different solutions of chitosan metal colloids. Then, the minimum and maximum concentration were determined for copper, nickel and cobalt. The purpose of the use of chitosan was acting as a carrier for some magnetic NPs, which toxicity would allow to obtain new polymeric materials with potential applications as magnet future drugs carrier.