Hydrothermal Route to Injectable Nanohybrid Drug Delivery Systems
Ewha Womans University, South Korea
An attempt is made to describe an emerging convergence science: “nanomedicine”. In particular, inorganic compounds such as anionic clays, layered double hydroxides (LDHs), at nanoscale, are underlined, with regard to how they could interact with bioactive and/or drug molecules to form novel intercalative hybrid drug systems with biocompatibility, imaging and targeting functions eventually for gene and/or drug delivery. In this regard, LDHs are focused as an important inorganic biomaterial for drug and gene delivery carriers with very high additive value in the near future, especially in biomedical industries including pharmaceutical, cosmeceutical, and nutraceutical ones, compared to any other industrial applications. In this study, the hydrothermal route to injectable drug delivery systems (IDDS)based on clay nanoparticles are described. And the nanotoxicity, intercellular uptake mechanism, and intracellular trafficking pathways in vitro for those IDDSs are discussed in detail, and finally passive and active targeting functions in vivo. In addition, several studies highlighting recent advances in chemotherapy with colloidal LDHs are also discussed, from the viewpoint of state-of-the-art convergence technology based on nanomedicine.
2:00pm - 2:30pm Invited
Bio-Inspired Nanoarchitectonics of Multi-Metallic Complexes for the Hybridization with Biomolecules
National Institute for Materials Science, Japan
One of the most important molecular architectures for any living species is polypeptide, whose chemical synthesis nowadays is mainly operated via highly established solid-phase synthesis protocols. By applying this technique for the sequential coupling of metallated amino acids, we recently developed a new synthetic method to make multi-metallated peptide arrays with a controlled sequence of metal complexes [1–4]. The protocols allow us to synthesize three isomeric trimetallic arrays, one of which showed larger gelation capability than the other two . A water-soluble array that displays unconventional anion dependency in its self-assembly as a peptide amphiphile [6, 7] and the results of hybridization of similar arrays with biomolecules such as peptides and DNA will be also presented.
 J. Am. Chem. Soc. 133, 759 (2011).
 C&EN89, 8 (2011).
 Inorg. Chem.54, 1197 (2015).
 Inorg. Chem.51, 6437 (2012).
 Chem. Commun. 2016, 52, 1759.
 Journal of Visualized Experiments116, JoVE 54513 (2016).
2:30pm - 3:00pm Invited
Biomimetic Apatites: Focus on their Surface State and Evolution in Solution for the Setup of Advanced Bioactive Materials
Christophe DROUET, Christian REY, David GROSSIN, Christele COMBES, Stéphanie SARDA, Jérémy SOULIÉ, Ghislaine BERTRAND
CIRIMAT, UMR CNRS/INPT/UPS 5085, Université de Toulouse, France
Biomimetic nanocrystalline apatites occupy a key position in biomedical applications due to their high analogy to bone mineral, in terms of chemical composition, nonstoichiometry, (micro)structure, surface state and reactivity. Provided that a close-to-physiological process is set up for elaborating such compounds, through adapted synthesis and processing conditions, the bioceramics obtained (e.g. via powder or gel consolidation) are particularly appealing for biomedical applications, for example in the field of bone regeneration in view of the production of bioactive and resorbable scaffolds. Moreover, the exceptional surface reactivity of nanocrystalline apatites, like in bone, allows ion exchanges and adsorptions of (bio)molecules providing tailor-made functionalities (e.g. promoted osteoconduction, antibacterial activity, radio opacity, hemostatic properties…). However, synthesis and post-synthesis parameters have to be appropriately controlled to allow the preparation of biomimetic apatite-based systems while preserving their nanocrystalline and hydrated characters which are among their key features. Also, nonstoichiometric apatites are metastable compounds, and a thermodynamic driving force controls their evolution when in humid conditions, allowing (bio)materials scientists to tailor their reactivity.
In this contribution, the main features of biomimetic apatites will be presented, with a special focus dedicated to their peculiar surface state (as opposed to stoichiometric hydroxyapatite for example) and to their evolution in solution. Different low-temperature approaches will then be displayed in view of producing (multi)functionalized biomimetic-apatite-based biomaterials for medical applications.
3:00pm - 3:15pm Oral
Solution Processed Li5AlO4 Dielectric Based for Low Voltage Transparent Transistor
Anand SHARMA, Nitesh K CHOURASIA, Bhola N PAL
Indian Institute of Technology Varanasi, India
Solution processed high-dielectric constant (k) inorganic gate insulator have received much attention as a key element of low voltage thin film transistors (TFTs) due to their high dielectric constant and low cost. Additionally, their coherent interface formation with solution processed oxide semiconductors lead to considerable improvements in TFT performance and make it possible to all solution processed TFT fabrication. In our present work we have developed high lithium ion (Li+) density Li5AlO4 ceramic thin film which required much lower annealing temperature range like from 300-500ºC and we observed maximum ionic conductivity in these range about 500ºC. The mobile ion density of this ceramic film is fifty times higher than earlier reported sodium beta alumina dielectric which makes a big difference of device performance with respect to earlier works. In combination, it shows much higher performance for low voltage transparent transistor fabrication with significantly lower temperature that clearly indicate a big step forward of earlier efforts of low voltage transistor fabrication. Our fabrication process is inorganic based transparent oxide dielectric and transparent amorphous semiconductor which is very low cost and solution processable these are best advantages over organic based transistor.
3:15pm - 3:30pm Oral
Fabrication of ZnO/PbS Nanocomposites for Room Temperature NO2 Sensing
Ruosong CHEN, Lan XIANG
Department of Chemical Engineering, Tsinghua University, China
ZnO nanostructures are promising candidates for gas sensors. An advanced ZnO/PbS hybrid nanostructures for detecting NO2 at room temperature was developed in this work. The ZnO/PbS hybrid nanostructures was fabricated by loading PbS nanoparticles (diameter: 4-5 nm) on ZnO nanowires (diameter: 20-30 nm, length:1.0-2.0 μm). Compared with the single ZnO nanowires based NO2 sensor, the ZnO/PbS hybrid nanostructures based NO2 sensor exhibited higher sensitivity. The sensitivity of the sensor made by the ZnO/PbS hybrid nanostructures to 10 ppm NO2 was 460% under infrared excitation at room temperature. The outstanding sensing performance of the ZnO NWs/PbS NPs nanocomposites was attributed to the excellent NO2 adsorption ability of the ultrathin ZnO nanowires as well as the synergetic eﬀect of ZnO and PbS, which was realized by the electron transfer from the narrow-bandgap PbS to the wide-bandgap ZnO under infrared excitation.