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Near-infrared Fluorescence Lifetime PH-sensitive Probes

Overview
Journal Biophys J
Publisher Cell Press
Specialty Biophysics
Date 2011 Apr 21
PMID 21504743
Citations 21
Authors
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Abstract

We report what we believe to be the first near-infrared pH-sensitive fluorescence lifetime molecular probe suitable for biological applications in physiological range. Specifically, we modified a known fluorophore skeleton, hexamethylindotricarbocyanine, with a tertiary amine functionality that was electronically coupled to the fluorophore, to generate a pH-sensitive probe. The pK(a) of the probe depended critically on the location of the amine. Peripheral substitution at the 5-position of the indole ring resulted in a compound with pK(a) ∼ 4.9 as determined by emission spectroscopy. In contrast, substitution at the meso-position shifted the pK(a) to 5.5. The resulting compound, LS482, demonstrated steady-state and fluorescence-lifetime pH-sensitivity. This sensitivity stemmed from distinct lifetimes for protonated (∼1.16 ns in acidic DMSO) and deprotonated (∼1.4 ns in basic DMSO) components. The suitability of the fluorescent dyes for biological applications was demonstrated with a fluorescence-lifetime tomography system. The ability to interrogate cellular processes and subsequently translate the findings in living organisms further augments the potential of these lifetime-based pH probes.

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References
1.
OLeary M, Boas D, Li X, Chance B, Yodh A . Fluorescence lifetime imaging in turbid media. Opt Lett. 2009; 21(2):158-60. DOI: 10.1364/ol.21.000158. View

2.
Kuwana E, Liang F, Sevick-Muraca E . Fluorescence lifetime spectroscopy of a pH-sensitive dye encapsulated in hydrogel beads. Biotechnol Prog. 2004; 20(5):1561-6. DOI: 10.1021/bp034328i. View

3.
Sevick-Muraca E, Houston J, Gurfinkel M . Fluorescence-enhanced, near infrared diagnostic imaging with contrast agents. Curr Opin Chem Biol. 2002; 6(5):642-50. DOI: 10.1016/s1367-5931(02)00356-3. View

4.
Dellian M, Helmlinger G, Yuan F, Jain R . Fluorescence ratio imaging of interstitial pH in solid tumours: effect of glucose on spatial and temporal gradients. Br J Cancer. 1996; 74(8):1206-15. PMC: 2075944. DOI: 10.1038/bjc.1996.518. View

5.
Berezin M, Lee H, Akers W, Achilefu S . Near infrared dyes as lifetime solvatochromic probes for micropolarity measurements of biological systems. Biophys J. 2007; 93(8):2892-9. PMC: 1989699. DOI: 10.1529/biophysj.107.111609. View