Fabrication of Bacteria Environment Cubes with Dry Lift-Off Fabrication Process for Enhanced Nitrification.

We have developed a 3D dry lift-off process to localize multiple types of nitrifying bacteria in polyethylene glycol diacrylate (PEGDA) cubes for enhanced nitrification, a two-step biological process that converts ammonium to nitrite and then to nitrate. Ammonia-oxidizing bacteria (AOB) is responsible for converting ammonia into nitrite, and nitrite-oxidizing bacteria (NOB) is responsible for converting nitrite to nitrate. Successful nitrification is often challenging to accomplish, in part because AOB and NOB are slow growers and highly susceptible to many organic and inorganic chemicals in wastewater.

Rational design of a bisphenol A aptamer selective surface-enhanced Raman scattering nanoprobe.

Surface-enhanced Raman scattering (SERS) optical nanoprobes offer a number of advantages for ultrasensitive analyte detection. These functionalized colloidal nanoparticles are a multifunctional assay component. providing a platform for conjugation to spectral tags, stabilizing polymers, and biorecognition elements such as aptamers or antibodies.

Solvent-free fabrication of polyHIPE microspheres for controlled release of growth factors.

The growth factor bone morphogenetic protein 2 (BMP-2) is utilized in surgical procedures to improve bone regeneration; however, current treatments deliver BMP-2 at amounts greater than 100,000 fold of physiological levels, which increases treatment costs and risk of side effects. Drug-eluting microcarriers developed to improve these therapies have faced significant commercialization challenges including particle size distributions, solvent removal, low encapsulation efficiency, and bioactivity loss. In this study, a solvent-free method is presented for fabrication of uniform polyHIPE microspheres for controlled growth factor release.

Thermoresponsive layer-by-layer assemblies for nanoparticle-based drug delivery.

Layer-by-layer (LbL) capsules, known for their versatility and smart response to environmental stimuli, have attracted great interest in drug delivery applications. However, achieving a desired drug delivery system with sustained and tunable drug release is still challenging. Here, a thermoresponsive drug delivery system of solid dexamethasone nanoparticles (DXM NPs, 200 ± 100 nm) encapsulated in a model LbL assembly of tunable thickness consisting of strong polyelectrolytes poly(diallyldimethylammonium chloride)/poly(styrenesulfonate) (PDAC/PSS) is constructed.

Nanoparticle-based biocompatible and targeted drug delivery: characterization and in vitro studies.

Paclitaxel nanoparticles (PAX NPs) prepared with the size of 110 ± 10 nm and ζ potential of -40 ± 3 mV were encapsulated in synthetic/biomacromolecule shell chitosan, dextran-sulfate using a layer-by-layer self-assembly technique. Zeta potential measurements, analysis of X-ray photoelectron spectroscopy, and scanning electron microscopy confirmed the successful adsorption of each layer. Surface modifications of these core-shell NPs were performed by covalently conjugating with poly(ethylene glycol) (H(2)N-PEG-carboxymethyl, M(w) 3400) and fluorescence labeled wheat germ agglutinin (F-WGA) to build a biocompatible and targeted drug delivery system.