2 research outputs found
Nile Blue-Based Nanosized pH Sensors for Simultaneous Far-Red and Near-Infrared Live Bioimaging
Diblock copolymer vesicles are tagged with pHresponsive
Nile Blue-based labels and used as a new type of
pH-responsive colorimetric/fluorescent biosensor for far-red
and near-infrared imaging of live cells. The diblock copolymer
vesicles described herein are based on poly(2-
(methacryloyloxy)ethyl phosphorylcholine-block-2-
(diisopropylamino)ethyl methacrylate) [PMPC-PDPA]: the
biomimetic PMPC block is known to facilitate rapid cell
uptake for a wide range of cell lines, while the PDPA block
constitutes the pH-responsive component that enables facile vesicle self-assembly in aqueous solution. These biocompatible
vesicles can be utilized to detect interstitial hypoxic/acidic regions in a tumor model via a pH-dependent colorimetric shift. In
addition, they are also useful for selective intracellular staining of lysosomes and early endosomes via subtle changes in
fluorescence emission. Such nanoparticles combine efficient cellular uptake with a pH-responsive Nile Blue dye label to produce
a highly versatile dual capability probe. This is in marked contrast to small molecule dyes, which are usually poorly uptaken by
cells, frequently exhibit cytotoxicity, and are characterized by intracellular distributions invariably dictated by their hydrophilic/
hydrophobic balance