Potentiometric pH Nanosensor for Intracellular Measurements: Real-Time and Continuous Assessment of Local Gradients
Mohaddeseh Amiri-Aref, Elias Ranjbari, Juan José García‐Guzmán, Keke Hu, Alicia A. Lork, Gastón A. Crespo, Andrew G. Ewing, María Cuartero
Abstract
), and a linear range of response including physiological and abnormal cell pH levels (6.0-8.5). In addition, the position and configuration of the reference electrode were investigated in cell-based experiments to provide unbiased pH measurements, in which both the indicator and reference electrodes were located inside the same cell, each of them inside two neighboring cells, or the indicator electrode inside the cell and the reference electrode outside of (but nearby) the studied cell. Finally, the pH nanosensor was applied to two cases: (i) the tracing of the pH gradient from extra-to intracellular media over insertion into a single PC12 cell and (ii) the monitoring of variations in intracellular pH in response to exogenous administration of pharmaceuticals. It is anticipated that the developed pH nanosensor, which is a label-free analytical tool, has high potential to aid in the investigation of pathological states that manifest in cell pH misregulation, with no restriction in the type of targeted cells.