dipyrromethene and boron-difluoride

Topics: Animals; Aza Compounds; Boron Compounds; Breast Neoplasms; Cell Line, Tumor; Dose-Response Relationship, Drug; Female; Fluorescent Dyes; Humans; Mammary Neoplasms, Experimental; Mice; Mice, Inbred BALB C; Molecular Structure; Optical Imaging; Polyethylene Glycols; Porphobilinogen; Renal Elimination; Spectrometry, Fluorescence; Structure-Activity Relationship

The recognition of the biological, diagnostic and medical importance of exosomes has given rise to an urgent need for efficient labelling of these extracellular vesicles in ways that do not alter their inherent characteristics. We report for the first time an endogenous method to NIR-fluorescent labelled exosomes using an amphiphilic probe without the need for immunolabelling or synthetic or chromatographic manipulation of exosomes. Comparative analyses of labelled and unlabelled exosomes with NTA, AFM, flow cytometry and immunoblot analysis all show a high degree of similarity. Spectroscopic analysis and fluorescence imaging confirmed the ability to visualise purified NIR-exosomes.

Topics: Aza Compounds; Boron Compounds; Cell Line, Tumor; Exosomes; Fluorescent Dyes; Humans; Infrared Rays; Optical Imaging; Porphobilinogen; Surface-Active Agents

The use of near-infrared fluorescence for in vivo research and intraoperative clinical imaging is rapidly expanding, with new applications being proposed and developed. While imaging hardware and software have significantly progressed in recent times, the molecular fluorescent agents remain a limiting factor. In this report, the design, synthesis, photophysical characterization and bio-medical imaging assessment of two new NIR-fluorophores based on the BF

Topics: Aza Compounds; Boron Compounds; Colon; Dose-Response Relationship, Drug; Fluorescent Dyes; Humans; Molecular Structure; Porphobilinogen; Spectroscopy, Near-Infrared; Structure-Activity Relationship

Evaluation of three subclasses of boron difluoride formazanate complexes bearing o-, m-, and p-anisole N-aryl substituents (Ar) as readily accessible alternatives to boron dipyrromethene (BODIPY) dyes for cell imaging applications is described. While the wavelengths of maximum absorption (λmax ) and emission (λem ) observed for each subclass of complexes, which differed by their carbon-bound substituents (R), were similar, the emission quantum yields for 7 a-c (R=cyano) were enhanced relative to 8 a-c (R=nitro) and 9 a-c (R=phenyl). Complexes 7 a-c and 8 a-c were also significantly easier to reduce electrochemically to their radical anion and dianion forms compared to 9 a-c. Within each subclass, the o-substituted derivatives were more difficult to reduce, had shorter λmax and λem , and lower emission quantum yields than the p-substituted analogues as a result of sterically driven twisting of the N-aryl substituents and a decrease in the degree of π-conjugation. The m-substituted complexes were the least difficult to reduce and possessed intermediate λmax , λem , and quantum yields. The complexes studied also exhibited large Stokes shifts (82-152 nm, 2143-5483 cm(-1) ). Finally, the utility of complex 7 c (Ar=p-anisole, R=cyano), which can be prepared for just a few dollars per gram, for fluorescence cell imaging was demonstrated. The use of 7 c and 4',6-diamino-2-phenylindole (DAPI) allowed for simultaneous imaging of the cytoplasm and nucleus of mouse fibroblast cells.

Topics: Anisoles; Boron Compounds; Crystallography, X-Ray; Diagnostic Imaging; Diamines; Fibroblasts; Fluorescence; Indoles; Models, Molecular; Molecular Structure; Porphobilinogen