Naphthalimide-Based Fluorescence Macrophage Sensors. Localization Selectivity through Substituent Chemical Manipulation

Abstract

The 1,8-naphthalimide scaffold is found among the most fruitful structures in the design of fluorophores with application in the development of fluorescence biosensors, due to its favorable photophysical properties, such as strong absorption and emission, large Stokes shifts, and photostability[1]. Considering that introduction of a nitrogen atom into the 1,8-naphtalimide skeleton could red-shift the fluorescence emission and increase water solubility, we have recently studied the design, synthesis and photophysical properties of 8-methoxy-4,5-quinolimides[2]. The photophysical properties of both scaffolds depend on the attached substituents and can be tuned by chemical manipulation. We have synthesized and will communicate new naphthalimide (A) and quinolimide (B) derivatives with a dimethylaminoethyl chain at the imide nitrogen atom, which behave as macrophage fluorescence sensors. Depending on the nature of the R substituent, these fluorophores can be used to imagine either the macrophage cytoplasm or the nucleus. The nucleus sensors bind DNA as intercalants.