A fluorescent ESIPT-based benzimidazole platform for the ratiometric two-photon imaging of ONOO- in vitro and ex vivo

Maria L Odyniec; Sang-Jun Park; Jordan E Gardiner; Emily C Webb; Adam C Sedgwick; Juyoung Yoon; Steven D Bull; Hwan Myung Kim; Tony D James

doi:10.1039/d0sc02347g

A fluorescent ESIPT-based benzimidazole platform for the ratiometric two-photon imaging of ONOO^- in vitro and ex vivo

Chem Sci. 2020 Jun 16;11(28):7329-7334. doi: 10.1039/d0sc02347g. eCollection 2020 Jul 28.

Authors

Maria L Odyniec¹, Sang-Jun Park², Jordan E Gardiner¹, Emily C Webb¹, Adam C Sedgwick³, Juyoung Yoon⁴, Steven D Bull¹, Hwan Myung Kim², Tony D James¹

Affiliations

¹ Department of Chemistry , University of Bath , BA2 7AY , UK . Email: T.D.James@bath.ac.uk ; Email: S.D.Bull@bath.ac.uk.
² Department of Chemistry , Ajou University , 16499 , Suwon , Korea . Email: kimhm@ajou.ac.kr.
³ Department of Chemistry , University of Texas at Austin , 105 E, 24th Street , A5300 , Austin , USA.
⁴ Department of Chemistry and Nano Science , Ewha Womans University , Seoul 120-750 , Korea.

Abstract

In this work, we have developed an ESIPT-based benzimidazole platform (MO-E1 and MO-E2) for the two-photon cell imaging of ONOO^- and a potential ONOO^--activated theranostic scaffold (MO-E3). Each benzimidazole platform, MO-E1-3, were shown to rapidly detect ONOO^- at micromolar concentrations (LoD = 0.28 μM, 6.53 μM and 0.81 μM respectively). The potential theranostic MO-E3 was shown to release the parent fluorophore and drug indomethacin in the presence of ONOO^- but unfortunately did not perform well in vitro due to low solubility. Despite this, the parent scaffold MO-E2 demonstrated its effectiveness as a two-photon imaging tool for the ratiometric detection of endogenous ONOO^- in RAW264.7 macrophages and rat hippocampus tissue. These results demonstrate the utility of this ESIPT benzimidazole-based platform for theranostic development and bioimaging applications.