Porous polymeric membranes: fabrication techniques and biomedical applications.

Porous polymeric membranes have shown great potential in biological and biomedical applications such as tissue engineering, bioseparation, and biosensing, due to their structural flexibility, versatile surface chemistry, and biocompatibility. This review outlines the advantages and limitations of the fabrication techniques commonly used to produce porous polymeric membranes, with especial focus on those featuring nano/submicron scale pores, which include track etching, nanoimprinting, block-copolymer self-assembly, and electrospinning. Recent advances in membrane technology have been key to facilitate precise control of pore size, shape, density and surface properties.

Solution processed polydimethylsiloxane/gold nanostar flexible substrates for plasmonic sensing.

Gold nanostars can display tunable optical properties in the visible and near IR, which lead to strong electromagnetic field enhancement at their tips. We report generalized application of gold nanostars for ultrasensitive identification of molecules, based on both localized surface plasmon resonance (LSPR) and surface enhanced Raman scattering (SERS). We address the requirements of plasmonic sensors, related to sufficiently large areas where nanoparticles are uniformly immobilized with high density, as well as mechanical flexibility, which offers additional advantages for real-world applications.

Sized controlled synthesis, purification, and cell studies with silicon quantum dots.

This article describes the size control synthesis of silicon quantum dots with simple microemulsion techniques. The silicon nanocrystals are small enough to be in the strong confinement regime and photoluminesce in the blue region of the visible spectrum and the emission can be tuned by changing the nanocrystal size. The silicon quantum dots were capped with allylamine either a platinum catalyst or UV-radiation.

Chemical reactions on surface molecules attached to silicon quantum dots.

This Article describes research on chemical reactions on molecules attached to the surface of silicon quantum dots that have been performed to produce quantum dots with reactive surface functionalities such as diols and epoxides. Characterization of the surface reactions includes NMR and FT-IR studies, and the quantum dots were characterized by transmission electron microscopy (TEM) and energy dispersive spectroscopy (EDS). Cytotoxicity and cell viability assay conducted on silicon dots capped with polar molecules indicated low toxicity with quantum dots with more reactive functionalities found to be more toxic.

On the cyto-toxicity caused by quantum dots.

Quantum dots (QDs) such as CdSe QDs have been introduced as new fluorophores. The QDs conjugated with antibody are starting to be widely used for immunostaining. However there is still not sufficient analysis of the toxicity of QDs in the literature.

Regioselective hydroxylation of the xylyl linker in a diiron(III) complex having a carboxylate-rich ligand with H2O2.

Reaction of a diiron(III) complex having a xylta4- ligand (N,N,N',N'-m-xylylenediamine tetraacetate) with H2O2 resulted in regioselective hydroxylation of the m-xylyl linker. The reaction mimics the self-hydroxylation of a phenylalanine side chain found for ribonucleotide reductase (R2-W48F/D84E).