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The combination of magnetic hyperthermia therapy with the controlled release of chemotherapeutic agents in tumors may be an efficient therapeutic with few side effects because the bioavailability, tolerance and amount of the drug can be optimized. Here, we prepared magnetoliposomes consisting of magnetite nanoparticle cores and the anticancer drug gemcitabine encapsulated by a phospholipid bilayer. The potential of these magnetoliposomes for controlled drug release and cancer treatment via hyperthermic behavior was investigated. The magnetic nanoparticle encapsulation efficiency was dependent on the initial amount of magnetite nanoparticles present at the encapsulation stage; the best formulation was 66%. We chose this formulation to characterize the physicochemical properties of the magnetoliposomes and to encapsulate gemcitabine. The mean particle size and distribution were determined by dynamic light scattering (DLS), and the zeta potential was measured. The magnetoliposome formulations all had acceptable characteristics for systemic administration, with a mean size of approximately 150 nm and a polydispersity index <0.2. The magnetoliposomes were stable in aqueous suspension for at least one week, as determined by DLS. Temperature increases due to the dissipation energy of magnetoliposome suspensions subjected to an applied alternating magnetic field (AMF) were measured at different magnetic field intensities, and the values were appropriated for cancer treatments. The drug release profile at 37 °C showed that 17% of the gemcitabine was released after 72 h. Drug release from magnetoliposomes exposed to an AMF for 5 min reached 70%.

The present experimental work was devoted to the chemical and mineralogical characterization of prehistoric rock paintings, of mineral pigments and of saline efflorescences from archaeological sites located in the states of Piauí, Bahia and Ceará, in Brazil, and in the Perito Moreno National Park, in Argentina. Samples were investigated in the laboratory by several analytical techniques, including (i) 57 Fe transmission and conversion electron Mössbauer spectroscopy; (ii) grazing incidence X-ray diffraction; (iii) energy dispersive spectroscopy; (iv) scanning electronic microscopy; (v) powder X-ray diffraction; (vi) energy dispersive X-ray fluorescence and (vii) Fourier-transform infrared spectroscopy. Results revelated that the red paintings were basically prepared with hematite (aFe 2 O 3 )-rich materials; the yellow paintings contained goethite (aFeOOH); the black paintings were essentially composed by carbon, presumably from charcoal (except the sample PCI-03, which was found to contain carbon together with hematite), and the gray painting was prepared with a mixture of carbon and aluminos licate minerals. The iron oxides and oxyhydroxides appear as being of small particle sizes, high isomorphic substituition of different cations for iron and low crystallinity. Results related to saline efflorescence samples revealed the occurrence of chabazite (Ca 2 Al 4 Si 8 O 24 .12H 2 O); partheite (Ca 2 Al 4 Si 4 O 15 (OH) 2 .4H 2 O); taranakite (H 6 K 3 Al 5 (PO 4 ) 8 .18H 2 O); newberyite (MgHPO 4 .3H 2 O); kaolinite (Al 2 Si 2 O 5 (OH) 4 ); brushite (CaPO 3 (OH).2H 2 O); gypsum (CaSO 4 .2H 2 O); KAl 3 (SO 4 ) 2 (OH) 6 ; potassium aluminum sulfate (KAl(SO 4 ) 2 ); K 2 SO 4 .7KHSO 4 .H 2 O and 5ZnO.Al 2 O 3 .ZnSO 4 .15H 2 O. The red pigments contained predominantly hematite, together with quartz, kaolinite, illite and KAl 3 (SO 4 ) 2 (OH) 6 , whereas the yellow pigment contained goethite, quartz and kaolinite. The white pigment was composed mainly by illite and quartz.

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