Acid‐Resistant BODIPY Amino Acids for Peptide‐Based Fluorescence Imaging of GPR54 Receptors in Pancreatic Islets

Abstract

Supporting information for this article is given via a link at the end of the document.

No-wash fluorogenic labeling of proteins for reversible photoswitching in live cells

“…Trp-BODIPY is an environmentally sensitive uorophore that emits green uorescence in high viscosity or hydrophobic environments. [31][32][33][34][35][36][37] In the previous study, we optimized the core structure of Trp-BODIPY, which has high environmental sensitivity and ease of synthesis. 32 Trp-BODIPY has lower uorescence quantum yields (F FL = 0.22 in phospholipid membranes 31 ) compared to the conventional meso-phenyl BODIPY (F FL = 0.65 in methanol 40 ) (chemical structures are shown in Fig.…”

“…This viscosity sensitivity is consistent with our previously reported Trp-BODIPY derivatives. [31][32][33][34][35][36][37] The viscosity sensitivity is closely related to the C-C bond rotation between the BODIPY core and the phenyl group. In high viscosity environments, this rotation is restricted, while the uorescence intensity is enhanced because the nonradiative decay is inactivated.…”

“…In this study, we have developed a novel PSFM named HTL-Trp-BODIPY-FF, which contains the Halo-tag ligand, 30 the environmentally sensitive uorophore Trp-BODIPY [31][32][33][34][35][36][37] and furylfulgimide (FF) 25,38,39 (Fig. 1a).…”

“…To achieve site-specic protein labeling in living cells, we chose the Halo-tag system, which is versatile for live-cell imaging applications, 30 and Trp-BODIPY, which exhibits brighter uorescence emission in hydrophobic environment. [31][32][33][34][35][36][37] HTL-Trp-BODIPY-FF exhibits limited uorescence emission in aqueous solutions predominantly due to the free rotation between the phenyl group and the BODIPY core which facilitates non-radiative decay rather than radiative decay as uorescence (OFF state). On the other hand, HTL-Trp-BODIPY-FF showed a uorescence intensity increase aer binding Halo-tag (ON state), because it was adjacent to the hydrophobic Halo-tag protein surface and sterically inhibited the rotation of the phenyl groups (Fig.…”

Smart probes for optical imaging of T cells and screening of anti-cancer immunotherapies

“…[1][2][3][4][5][6] Other smart chemical designs rely on targeting moieties that deliver fluorescent payloads in close proximity to proteins and receptors exposed on the cellular membrane. 7,8 Activatable fluorophores often exhibit higher signal-to-noise ratios than ''alwayson'' fluorophores, making them ideal for monitoring cellular function over time. [9][10][11] In addition to these favorable properties, smart probes can be also fine-tuned to display excitation and emission wavelengths in the near-infrared (NIR) region, where absorption and autofluorescence of endogenous biomolecules are minimal.…”