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Virus-mediated gene delivery has been, to date, the most successful and efficient method for gene therapy. However, this method has been challenged because of serious safety concerns. Over the past decade, mesoporous silica nanoparticles (MSNs) have attracted much attention for intracellular delivery of nucleic acids. Delivery of cellular plasmid DNA (pDNA) is designed to replace the function of a defective gene and restore its normal function in the cell. Delivery of small interfering RNAs (siRNAs) can selectively knockdown genes by targeting specific mRNAs. The biocompatibility and unique structures of MSNs make these nanoparticles ideal candidates to act as biomolecule carriers. This concise review highlights current progress in the field of nucleic acid delivery using MSNs, specifically for delivery of pDNA, siRNA, and combinatorial delivery of nucleic acids and drugs. The review describes important design parameters presently being applied to MSNs to administer drugs and therapeutic nucleic acids. [ABSTRACT FROM AUTHOR]

There is interest in developing potent, selective, and cell-permeable inhibitors of human ferrous iron and 2-oxoglutarate (2OG) oxygenases for use in functional and target validation studies. The 3-component Betti reaction enables efficient one-step C-7 functionalisation of modified 8-hydroxyquinolines (8HQs) to produce cell-active inhibitors of KDM4 histone demethylases and other 2OG oxygenases; the work exemplifies how a template-based metallo-enzyme inhibitor approach can be used to give biologically active compounds. [ABSTRACT FROM AUTHOR]

Abstract: This article presents recent results related to development of thick quasi-phase-matched GaP for incorporation in high power sources radiating in the mid-infrared. The focus was on increasing the growth rate and layer thickness of orientation patterned GaP, while ensuring equal vertical deposition rates and rectangular shape of the domain mesas for both opposite crystallographic lattice orientations. Additionally, we present solutions which confine the presence of uncontrollable hillock growth. The experiments were conducted in a hot-wall horizontal quartz reactor using a standard low-pressure hydride vapor phase epitaxial (HVPE) process. GaP was grown on bare, half-patterned (HP) and orientation-patterned (OP) templates fabricated on (100) GaP and (100) misoriented 4° towards (111)B substrates. The domains were oriented either along the [011] or the [011̄] direction. We compared a sub-lattice inversion MBE assisted process and a wafer fusion bonding technique to create OP templates. When the growth was performed on bare material, the properly chosen growth conditions resulted in reproducible growth of up to 370μm thick layers with high optical, surface and structural quality, grown at a growth rate of 100μm/h in one-hour long experiments and 45μm/h for 8-h long growths. The presence of a core inside the hillocks growing on the layer surface was eliminated. The hillocks were flattened and widened, which allowed often a single hillock to span several domains with alternating opposite crystallographic orientations, when growth was performed on patterned templates. The HP templates were used to determine the optimal substrate and pattern orientations prior to starting growth experiments on OP-templates. As an additional result they revealed that growth could be hillock-free for certain orientations. Growths on OP templates achieved stable growth rates of 50–70μm/h with domain walls propagating vertically. The growth followed the periodicity of the initial pattern. The maximal thickness achieved to date on OP GaP is about 350μm. [Copyright &y& Elsevier]