Fluorescence lifetime imaging of upper gastrointestinal pH in vivo with a lanthanide based near-infrared τ probe.

ABSTRACT: Time-resolved fluorescence lifetime imaging (FLIM) in the near-infrared region of 900-1700 nm not only allows a deep tissue penetration depth but also offers the unique benefit of the quantitative visualization of molecular events in vivo and is independent of local luminescence intensity and fluorophore concentration. Herein, we report the design of a wide-range pH sensitive molecular probe based on Yb³⁺ porphyrinate. The Yb³⁺ probe shows increasing NIR emission and lifetime with pK _a values of ca. 6.6 from pH 9.0 and 5.0 and also displays an elongated lifetime from ca. 135 to 170 μs at lower pH values (5.0-1.0) due to aggregation and reduced exposure to water at low pH values. Importantly, the probe is able to monitor a wide ra

SUBMITTER: Ning Y 

PROVIDER: S-EPMC6471977 | biostudies-literature | 2019 Apr

REPOSITORIES: biostudies-literature