Excitation-Dependent pKa Extends the Sensing Range of Fluorescence Lifetime pH Sensors.

ABSTRACT: Biological activity is strongly dependent on pH, which fluctuates within a variety of neutral, alkaline, and acidic local environments. The heterogeneity of tissue and subcellular pH has driven the development of sensors with different pKa values, and a huge assortment of fluorescent sensors have been created to measure and visualize pH in living cells and tissues. In particular, sensors that report based on fluorescence lifetime are advantageous for quantitation. Here, we apply a theoretical framework to derive how the apparent pKa of lifetime-based pH sensors depends on fluorescence excitation wavelength. We demonstrate that theory predicts the behavior of two different fluorescent protein-based pH sensors in solution as proofs-of-concept. Furthermore, we show that this behavior has grea

SUBMITTER: Haynes EP 

PROVIDER: S-EPMC11644319 | biostudies-literature | 2024 Nov

REPOSITORIES: biostudies-literature