Process for preparing alumina gel in a single precipitation step consisting of dissolving an aluminium precursor, aluminium chloride, in water, at a temperature of 10 C. to 90 C. such that the pH of the solution is from 0.5 to 5, for a period of 2 to 60 minutes, then adjusting the pH to 7.5 to 9.5 by adding a basic precursor, sodium hydroxide, to the solution obtained to obtain a suspension, at a temperature of 5 C. to 35 C., and for 5 minutes to 5 hours, followed by a filtration step, said process not comprising any washing steps. Also, novel alumina gel having a high dispersibility index, in particular a dispersibility index of more than 80%, a crystallite dimension of 0.5 to 10 nm, a chlorine content of 0.001% to 2% by weight and a sodium content of 0.001% to 2% by weight, the percentages by weight being expressed with respect to the total weight of the alumina gel.

The invention provides a new method for preparing ultra-small polymeric-lipidic delivery nanoparticles (USDNs) that were synthesized by a nanoprecipitation method followed by a layer-by-layer nanodeposition. The USDNs particle size can be controlled between 5-25 mn and provides loading capacities of 22.12% to 72.08%. Moreover, the USDNs platform provides pH controlled drug release, within a terminal release ratio of 68% at pH 5.0 and almost no release to pH of 7.5. Furthermore, based on their small sizes (5-25 nm) and unique composition, the USDNs penetrates the skin strata efficiently, release the payload at the target site as topical or transdermal treatment of a variety of skin disorders. Additionally the USDNs system can be used to treat and diagnoses other crucial diseases (Cancer, Alzheimer, etc) can be combined with various micro-needles or needles free array technologies for special application.

There is set forth herein a method for providing a nanoparticle array. A nanoparticle network can be provided by nanoparticles combined with surfactant micelle chains. The nanoparticle network can be provided by distributing metal nanoparticles in a surfactant solution and agitating the surfactant solution comprising the nanoparticles to form a gel comprising the nanoparticle network which can be characterized by a distributed array of nanoparticles combined with surfactant micelle chains within a fluid. The gel can comprise a fluid in a continuous phase and the nanoparticles in a discontinuous phase. Apparatus having arrays of nanoparticles are also set forth herein.

Methods of making robust bijels include dispersing metal oxide precursors and/or metal salts into at least one phase of a bijel and hydrolyzing and condensing the metal oxide precursors and/or metal salts in a sol-gel reaction to form sintered bridges between interfacially jammed surface-active nanoparticles. The methods can be used with any bijels, including those produced during solvent transfer-induced phase separation (STRIPS) methods and other methods. A robust bijel includes chemically sintered bridges between the interfacially jammed surface-active nanoparticles. Methods of making nanocatalyst-functionalized sintered bijels include adsorbing metal salts to a surface of sintered interfacially jammed nanoparticles of bijels, and reducing the metal precursors on the surface of the sintered nanoparticles. Nanocatalyst-functionalized sintered bijels include catalytically active metal or metal oxide nanocatalysts on a surface of the sintered interfacially jammed surface-active nanoparticles.