Potassium Sensitive Optical Nanosensors Containing Voltage Sensitive Dyes

Abstract

Ionophore-based ion-selective optical nanosensors have been explored for a number of years. Voltage sensitive dyes (VSDs) have been introduced into this type of sensors only very recently, forming a new class of analytical tools. Here, K + -sensitive nanospheres incorporating a lipophilic VSD were successfully fabricated and characterized. The nanosensors were readily delivered into the social amoeba Dictyostelium discoideum in a non-invasive manner, forming a promising new platform for intracellular ion quantification and imaging.

Continuous Fluorescence Imaging of Intracellular Calcium by Use of Ion-Selective Nanospheres with Adjustable Spectra

“…Selectivity of the optode is determined by the ionophores, so that high specificity is maintained to measure the target ion . Recently, Bakker and co-workers ,,− utilized the precipitation approach to prepare monodisperse ion-selective nanospheres for determination of aqueous ions. In their strategy, all sensing components were dissolved in tetrahydrofuran and mixed with aqueous solution subsequently.…”

Chloride ion-selective dye liquid nanoemulsion: improved sensor performance due to intermolecular interactions between dye and ionophore

“…6–11 Of these, nanoemulsion-type optodes (NE optodes) have various advantages. 6,22–27 For instance, their response times are significantly shortened owing to their large specific surface area. 6,22,23 NE optodes can not only be subjected to easy surface modification, but also measure intracellular ions when introduced into cells, which is not possible with thin membrane-type optodes.…”

Fluorescence Lifetime-Resolved Ion-Selective Nanospheres for Simultaneous Imaging of Calcium Ion in Mitochondria and Lysosomes

“…Ion selective nanospheres are a new type of optical sensors for the detection of ions, which consist of special ionophore, ion exchanger, and chromoionophore in the core and Pluronic F127 (polyoxyethylene-polyoxypropylene block copolymer) as the shell layer. − The ionophores with excellent selectivity are responsible to recognize the target ion. Upon the exposure of the nanospheres to the target ion, the ion exchange and the following binding of ion with the ionophore results in the release of hydrogen ions.…”