02053nas a2200157   4500008004100000022001400041245009400055210006900149260006700218300001400285490000700299520144200306100001601748700001401764856011701778       2005                        eng d  a8756-793800aFree-standing nanogold membranes as supports for the growth of calcium phosphate crystals0 aFreestanding nanogold membranes as supports for the growth of ca  a111 RIVER ST, HOBOKEN 07030-5774, NJ USAbWILEY-BLACKWELLcNOV  a1759-17670 v213 a<p>Current strategies for bone tissue regeneration focus on the development of implantable matrices that mimic biological tissues. Inorganic composites are of special interest for bone substitute applications. It is necessary to create an artificial three-dimensional scaffold-like porous material with certain geometrical structure to induce bone growth. We report here the growth of calcium phosphate crystals on free-standing carboxylic acid functionalized gold nanoparticle membranes. The gold nanoparticle membrane is synthesized by the spontaneous reduction of aqueous chloroaurate ions by a diamine molecule at a liquid-liquid interface. This membrane is robust and malleable, and most importantly, the gold nanoparticles in the membrane may be functionalized with suitable ligands. In this study, the amino acids aspartic acid and cysteine together with an aromatic bifunctional molecule, anthranilic acid, were used to modify the surface of the gold nanoparticles in the membrane. The free carboxylic acid groups on the gold nanoparticles further to functionalization with these molecules were then used to bind Ca2+ ions and reacted with phosphate ions to yield calcium phosphate. The nature of the nanogold surface modifier directed the formation of either crystalline hydroxyapatite or amorphous calcium phosphate. The nanogold membrane thus suggests potential biomedical application as biocompatible implants and grafts.</p>1 aRautaray, D1 aSastry, M  uhttps://library.ncl.res.in/content/free-standing-nanogold-membranes-supports-growth-calcium-phosphate-crystals-002340nas a2200169   4500008004100000022001400041245012100055210006900176260011000245300001200355490000800367520162400375100001601999700001802015700001402033856012302047       2005                        eng d  a1364-549800aUsing the dynamic, expanding liquid-liquid interface in a Hele-Shaw cell in crystal growth and nanoparticle assembly0 aUsing the dynamic expanding liquidliquid interface in a HeleShaw  aTHOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLANDbROYAL SOC CHEMISTRYcJAN  a205-2170 v1293 a<p>The liquid-liquid interface has been used with considerable success in the synthesis of advanced materials ranging from (bio)minerals to inorganic membranes to nanoparticles. In almost all such cases, the interface is static. The Hele-Shaw cell in which a viscous fluid is displaced by a less viscous one in a constrained manner has been invaluable in the study of dynamic instabilities at interfaces and in the study of viscous fingering pattern formation. However, the potential of the Hele-Shaw cell in carrying out reactions at the interface between the two fluids leading to the formation of inorganic materials has been largely unrecognized and underexploited. Realizing that the dynamic liquid-liquid interface in a Hele-Shaw cell would provide opportunities to control a variety of time-scales associated with material formation, we have started a program on the use of the Hele-Shaw cell in materials synthesis. In this discussion paper, we present some of our recent results on the growth of calcium carbonate crystals in the Hele-Shaw cell by the reaction of Ca2+ ions electrostatically complexed with carboxylate ions pinned to the interface with carbonate ions present in the aqueous part of the biphasic reaction medium. We show that both polymorph selectivity and the morphology of the crystals may be modulated by varying the experimental conditions in the cell. We also discuss the possibility of using the dynamic interface in the Hele-Shaw cell to cross-link gold nanoparticles in water through bifunctional linkers present in the oil phase and investigate the nature of the structures formed.</p>1 aRautaray, D1 aKavathekar, R1 aSastry, M  uhttps://library.ncl.res.in/content/using-dynamic-expanding-liquid-liquid-interface-hele-shaw-cell-crystal-growth-and-0