A simple FRET-based modular design for diagnostic probes

Abstract

In recent years, there has been a massive effort to develop molecular probes with optical modes of action. Probes generally produce detectable signals based on changes in fluorescence properties. Here, we demonstrate the potential of self-immolative molecular adaptors as a platform for Turn-On probes based on the FRET technique. The probe is equipped with identical fluorophore pairs or a fluorophore/quencher FRET pair and a triggering substrate. Upon reaction of the analyte of interest with the triggering substrate, the self-immolative adaptor spontaneously releases the two dye molecules to break off the FRET effect. As a result, a new measurable fluorescent signal is generated. The fluorescence obtained can be used to quantify the analyte. The modular structure of the probe design will allow the preparation of various chemical probes based on the FRET activation technique.

Modular theranostic prodrug based on a FRET-activated self-immolative linker

“…1 H-NMR spectra were measured using Bruker Avance operated at 200 MHz. 13 C-NMR spectra were measured using Bruker Avance operated at 50 MHz. The chemical shifts are expressed in δ relative to TMS (δ = 0 ppm), and coupling constants, J, are given in Hz.…”

“…The crude product was purified by column chromatography on silica gel (MeOH:EtOAc, 5:95) to give compound 13 (11 mg, 80%) as a white solid. 13 …”

Polymeric nanotheranostics for real-time non-invasive optical imaging of breast cancer progression and drug release

“…Cy5-COOH was synthesized as previously described [22]. Next, Cy5-COOH fluorophore was conjugated with HPMA copolymer-GFLG-en in two-step synthesis.…”

“…The donor is always a fluorophore, however the acceptor can be either a quencher -a dye with no native fluorescence (FRET) or a second fluorophore (self-quenching) [22]. When a FRET fluorophorequencher process occurs, the excited fluorophore can transfer its emission energy to the nearby quencher.…”

Photophysical Characterization and BSA Interaction of Direct Ring Carboxy Functionalized Symmetrical squaraine Dyes

“…Changes in the fluorescence behaviour of dyes on interactions with biomolecules forms the fundamental basis for fluorescence bio-imaging. Spectroscopic behaviour of squaraine dyes have been reported to be highly sensitive to the environmental conditions due to their self-aggregation [22]. In common, fluorophores bind with protein covalently or non-covalently and non-covalent binding or labelling shows preference for hydrophobic binding sites, where it finds potential application in biomedical science in order to investigate the changes in the conformation of proteins and their binding with drugs [18].…”