ZnO films grown by pulsed-laser deposition on c-plane Al 2 O 3 substrates were annealed at temperatures up to 600°C to produce n-type carrier concentrations in the range 7.5ϫ10 15-1.5 ϫ10 20 cm Ϫ3. After high-dose (3ϫ10 16 cm Ϫ2) Mn implantation and subsequent annealing at 600°C, all the films show n-type carrier concentrations in the range 2-5ϫ10 20 cm Ϫ3 and room temperature hysteresis in magnetization loops. The saturation magnetization and coercivity of the implanted single-phase films were both strong functions of the initial anneal temperature, suggesting that carrier concentration alone cannot account for the magnetic properties of ZnO:Mn, and that factors such as crystalline quality and residual defects play a role.

1The aim of this study was to compare protein-loaded inhalable microparticles 2 manufactured using a range of biocompatible polymers including hydroxypropyl cellulose 3 (HPC), chitosan, hyaluronic acid, alginate, gelatin, ovalbumin and poly (lactide-co-4 glycolide)(PLGA). Spray drying was used to prepare microparticles containing bovine 5 serum albumin labeled with flourescein isothiocyanate (BSA-FITC). Particles of respirable 6 size and high protein loading were obtained. No evidence of BSA degradation was seen 7 from PAGE analysis. The microparticles were mixed with mannitol as a carrier and 8 powder aerosolization was assessed with a multi-dose dry powder inhaler (DPI) using a 9 multi-stage cascade impactor. The mass median aerodynamic diameter (MMAD) ranged 10 between 2.9-4.7m. Potential polymer toxicity in the lungs was compared by impinging 11 the particles on Calu-3 monolayers and assessing the cytotoxicity, induction of cytokine 12 release, changes in transepithelial permeability and electrical resistance. No toxic effects 13were observed with most of the polymers though some evidence of compromised cell 14 monolayer integrity was seen for PLGA and ovalbumin. PLGA and gelatin microparticles 15 caused a significant increase in IL-8 release. Of the polymers studied, PLGA showed the 16 greatest toxicity. Certain polymers showed particular promise for specific protein delivery 17 needs in the lungs, such as HPC to improve flow properties, sodium hyaluronate for 18 controlled release, and chitosan and ovalbumin for systemic delivery. 19

No abstract

ZnO nanorods with diameters of 15-30 nm were grown on Ag-coated Si substrates by catalyst-driven molecular beam epitaxy and then implanted with Mn ϩ or Co ϩ ions to doses of 1 -5ϫ10 16 cm Ϫ2 . After subsequent annealing at 700°C for 5 min, the structural properties of the nanorods were unaffected, but they exhibited ferromagnetism that persisted to temperatures of 225-300 K. The coercive fields were р100 Oe even at 10 K. The results are similar to those obtained for implantation of Mn ϩ or Co ϩ ions in bulk single-crystal ZnO and indicate promise for nanorods for nanoscale spintronic applications.

A study of single-dose digoxin kinetics was performed in 6 young and 7 elderly patients. The rate of absorption, determined by the time to peak concentration after an oral dose, was more rapid in the younger group. The extent of absorption, as measured by comparison of the area under the plasma concentration/time curve after oral and intravenous administration, was similar in both groups. Mean plasma half-life was longer and individual values were more variable in the elderly patients. The absolute apparent volume of distribution was reduced in the older patients and correlated inversely with age. When corrected for weight, however, the difference in the apparent volume of distribution did not approach significance. Both absolute and weight-corrected values for plasma clearance of digoxin were reduced in the elderly subjects.