High-perfomance fluorescent dyes for in vitro and in vivo applications

With the development of highly sensitive imaging techniques, studies based on in vitro and in vivo fluorescence detection have become widespread. Fluorescent methods make it possible to solve such problems as the detection of single molecules and individual cells; visualization of submicron objects in molecular biology using fluorescence microscopy; cell counting, sorting and biomarker detection; fluorescence can also be used to search for target molecules, for example, in studies of cell oxidative stress , determination of nitric oxide in vivo, immunological analysis, amplification detection in real-time PCR and genomic sequencing.

Borondipyrromethene (BDP) based fluorophores are promising scaffold due to combination of valuable properties. They are characterized by high fluorescence quantum yields aqueous media included, narrow absorption and fluorescence bands, which makes it possible to clearly detect the signal; high photostability is also their advantage over various analogues.

Colour (at the top) and light emission (at the bottom) of BDP type dyes.

Dozens of fluorescent dyes from various companies based on BDP are currently on the market. Most of them are characterized by low hydrophilicity and, as a result, have a tendency to form supramolecular complexes in an aqueous medium, which leads to a distortion of research results, as well as difficulties in obtaining dye conjugates with biomolecules are probable.

Research aimed at obtaining water-soluble high photostability and bright fluorescent dyes is a challenging scientific problem.

Biotech Innovations LLC is developing this kind of fluorophores. A number of borondipyrromethene dyes have been developed which are characterized by high hydrophilicity/photostability. In terms of photophysical characteristics the photostability is increased up to 4 times). The BDP derivatives synthesized are superior to commercial analogues (the Stokes shift 2 fold wider, the energy losses are reduced by 2-10 fold, the extinction coefficients are 20% higher).

Colour (on the lefthand) and light emission (on the righthand) of a BDP dye carrying sulfonic groups and huge aryl substituent с сульфогруппами и арильным заместителем (справа) и его флуоресценция (слева)

Specific features of BDP dyes is smaller number of methyl substituents in the borondipyrromethene core, sulfonic groups, huge hydrophylic aryl substituents.

Reactive derivatives of these dyes that can be used for conjugation in click chemistry reactions and N-hydroxysuccinimidyl derivatives have been developed; efficient chemical interaction with oligonucleotide and protein molecules proved which confirm potential applications as biological molecules’ tags.