Emulsion Doping of Ionophores and Ion-Exchangers into Ion-Selective Electrode Membranes.

Ion-selective electrodes (ISEs) are widely used analytical devices to selectively measure ionic species. Despite significant advances in recent years, ion-selective membranes are still mostly prepared in the same manner, by preloading the selective components into a solvent that is subsequently cast into a membrane or film. This paper describes an alternative method to prepare ISE membranes by mass transfer of the sensing components from an emulsion phase.

Surface-Doped Polystyrene Microsensors Containing Lipophilic Solvatochromic Dye Transducers.

Ion-selective optical microsensors based on surface-modified polystyrene (PS) beads with positively charged lipophilic solvatochromic dye (SD) on the surface were studied with K as model ion. Water-soluble SDs are expelled into the aqueous phase by ion exchange with the cationic analyte of interest, resulting in a detectable color change. In contrast, lipophilic SDs are more attractive, as they appear to remain anchored to the surface after expulsion from the sensing phase.

Co-localization of the amyloid precursor protein and Notch intracellular domains in nuclear transcription factories.

The beta-amyloid precursor protein (APP) plays a major role in Alzheimer's disease. The APP intracellular domain (AICD), together with Fe65 and Tip60, localizes to spherical nuclear AFT complexes, which may represent sites of transcription. Despite a lack of co-localization with several described nuclear compartments, we have identified a close apposition between AFT complexes and splicing speckles, Cajal bodies and PML bodies.

The APP intracellular domain forms nuclear multiprotein complexes and regulates the transcription of its own precursor.

The physiological functions of the beta-amyloid precursor protein (APP) may include nuclear signaling. To characterize the role of the APP adaptor proteins Fe65, Jip1b, X11alpha (MINT1) and the chromatin-associated protein Tip60, we analyzed their interactions by confocal microscopy and co-immunoprecipitations. AICD corresponding to S3-cleaved APP bound to Fe65 that transported it to nuclei and docked it to Tip60.