Pharm Res 2009,26(11):2495–2503.CrossRef 44. Zhang Y, Tang L, Sun L, Bao J, Song C, Huang L, Liu K, Tian Y, Tian G, Li Z, Sun H, Mei L: A novel paclitaxel-loaded poly (ε-caprolactone)/poloxamer 188 blend nanoparticle overcoming multidrug resistance for RG-7388 nmr cancer treatment. Acta Biomater 2010,6(6):2045–2052.CrossRef 45. Hasegawa M, Yagi K, Iwakawa S, Hirai M: Thiolated chitosan induces apoptosis via caspase-3 activation in lung tumor cells. Jpn J Cancer Res 2001,92(4):459–466.CrossRef Competing interest The authors declare that see more they have no competing interests. Authors’ contributions LJ carried out the polymer synthesis, nanoparticle preparation, and cell studies. XL carried out

the polymer and nanoparticle characterizations. LL carried out the ex

vivo studies and participated in the design of the study. QZ conceived the study and participated in its design and coordination. All authors read and approved the final manuscript.”
“Background III-Nitride semiconductor nanowires (NWs) have recently attracted great interest due to Nirogacestat supplier their potential applications including light-emitting diodes (LEDs), lasers, photodetectors, gas sensors and solar cells [1–5]. The direct growth of NWs on conductive substrates benefits from a direct electrical backside contact that can considerably simplify the device processing. In this context, silicon wafers present several attractive advantages to be employed as n- or p-type conductive substrates such as scalability (up to 12 in.), good thermal conductivity and low cost. The planar growth of GaN on Si substrates is challenging because of the large lattice and thermal dilatation mismatches that create high dislocation densities and Etofibrate residual strains. The NW geometry is known to improve these two drawbacks by decreasing the dislocation density along the wire length and releasing the strain with the free surface relaxation. The growth of GaN NWs on Si (111) has been mainly developed by catalyst-free molecular beam epitaxy (MBE) using an intermediate interfacial AlN layer to improve the epitaxial relationships [6, 7]. Such nanowires

exhibit excellent optical properties and have been successfully integrated in LED devices [8]. Metal organic vapour-phase epitaxy (MOVPE), which is widespread in the industry for planar growths, has been used to address the growth of catalyst-free GaN wires [9–11]. But surprisingly, the MOVPE growth of GaN wires on Si (111) substrate has been reported only recently using deposited Al [12] and AlN [13] intermediate layers. The roles of these thin layers on the epitaxial relationships between the substrate and the wires and their impact on the LED electrical injection have not been reported yet. These two points will be studied in this paper by growing n-doped GaN wires by MOVPE on a thin AlN layer deposited on n-type Si (111) substrates.