In an earlier study we demonstrated that hydroxyapatite nanoparticles coated with chitosan-poly(D,L)-lactide-co-glycolide (HAp/Ch-PLGA) target lungs following their intravenous injection into mice. In this study we utilize an emulsification process and freeze drying to load the composite HAp/Ch-PLGA particles with 17β-hydroxy-17α-picolyl-androst-5-en-3β-yl-acetate (A), a chemotherapeutic derivative of androstane and a novel compound with a selective anticancer activity against lung cancer cells. 1H NMR and 13C NMR techniques confirmed the intact structure of the derivative A following its entrapment within HAp/Ch-PLGA particles. The thermogravimetric and differential thermal analyses coupled with mass spectrometry were used to assess the thermal degradation products and properties of A-loaded HAp/Ch-PLGA. The loading efficiency, as indicated by the comparison of enthalpies of phase transitions in pure A and A-loaded HAp/Ch-PLGA, equaled 7.47 wt.%. The release of A from HAp/Ch-PLGA was sustained, neither exhibiting a burst release nor plateauing after three weeks. Atomic force microscopy and particle size distribution analyses were used to confirm that the particles were spherical with a uniform size distribution of d50 = 168 nm. In vitro cytotoxicity testing of A-loaded HAp/Ch-PLGA using MTT and trypan blue dye exclusion assays demonstrated that the particles were cytotoxic to the A549 human lung carcinoma cell line (46±2%), while simultaneously preserving high viability (83±3%) of regular MRC5 human lung fibroblasts and causing no harm to primary mouse lung fibroblasts. In conclusion, composite A-loaded HAp/Ch-PLGA particles could be seen as promising drug delivery platforms for selective cancer therapies, targeting malignant cells for destruction, while having a significantly lesser cytotoxic effect on the healthy cells.

Lithium iron phosphate powders were obtained by solvothermal treatments of quaternary emulsions Triton X-100/cyclohexane/n-hexanol/water at low temperature (180 ºC), with or without stirring. Such synthesis conditions allowed for fast crystallization of pure olivine-type LiFePO 4 powder, evidenced by the X-ray powder diffraction measurements and energy dispersive spectroscopy. It has been found that stirring drastically changes the morphology of LiFePO 4 particles, causing a preferential crystal orientation. Also, a great difference in the morphology was demonstrated by field emission scanning electron microscopy. The powder obtained after only half an hour of the dynamic solvothermal treatment, without additional post annealing, and without carbon coating, was electrochemically active, showing the discharge capacity of 115 mAh/g.

a b s t r a c tThe olivine type LiFePO 4 is synthesized via a simple and inexpensive route by aqueous co-precipitation of an Fe(II) precursor material in molten stearic acid and subsequent heat treatment at different temperatures. Stearic acid serves as both chelating agent and carbonaceous material. The obtained composites with carbon are characterized by X-ray powder diffraction, field emission scanning electron microscopy, and Mössbauer spectroscopy. Electrochemical characteristics of the composites are evaluated by using galvanostatic charge/discharge tests. The powder obtained at 700 • C delivers discharge capacity of 160 mAh g −1 , quite near the theoretical value.