Using the heme peroxidase APEX2 to probe intracellular HO flux and diffusion.

Currently available genetically encoded HO probes report on the thiol redox state of the probe, which means that they reflect the balance between probe thiol oxidation and reduction. Here we introduce the use of the engineered heme peroxidase APEX2 as a thiol-independent chemogenetic HO probe that directly and irreversibly converts HO molecules into either fluorescent or luminescent signals. We demonstrate sensitivity, specificity, and the ability to quantitate endogenous HO turnover.

Poly(4-Styrenesulfonic Acid--maleic Anhydride)-Coated NaGdF:Yb,Tb,Nd Nanoparticles with Luminescence and Magnetic Properties for Imaging of Pancreatic Islets and β-Cells.

Novel Yb,Tb,Nd-doped GdF and NaGdF nanoparticles were synthesized by a coprecipitation method in ethylene glycol (EG) in the presence of the poly(4-styrenesulfonic acid--maleic anhydride) stabilizer. The particle size and morphology, crystal structure, and phase change were controlled by adjusting the PSSMA concentration and source of fluoride anions in the reaction. Doping of Yb, Tb, and Nd ions in the NaGdF host nanoparticles induced luminescence under ultraviolet and near-infrared excitation and high relaxivity in magnetic resonance (MR) imaging (MRI).