Synthesis?Optical Properties Of Anthracene Ring-Like Structure Dyes And Their Applications In Protein Labeling

Protein glycosylation is one of the most common post-translational modifications(PTMs).It involves attaching carbohydrates at specific sites in the protein backbone.Thus glycans play a key role in physiological events involving health and disease.At present,in the analysis of sugar chain structure,fluorescent-labeled lectin microarray technology has become the main method.The method is simple and sensitive in the process of detecting sugar chains,and the most important one is that it can achieve high throughput compared with the conventional detection method,so it is more efficient.In the application of fluorescently labeled lectin microarray technology,more cyanine dye series are currently used,which can better label purified biomacromolecules by covalent coupling.However,such dyes also have different disadvantages due to structural differences.Some dyes have small Stokes shift,which often leads to self-quenching during application,which leads to errors in fluorescence detection.Some dyes have good optical properties,but the synthesis process is complicated and expensive,which limits or reduces the scope of use.Therefore,there is an urgent need to develop new fluorescent dyes with good spectral properties and low cost for labeling proteins.Through the analysis of the classical oxindole structure dyes,we modified its structure and introduced a functional group carboxyl group capable of covalently binding with proteins to synthesize 11 new fluorescent dyes in three major categories.Moreover,for each new dye,we have conducted a detailed and comprehensive study of its optical properties and practical applications.The specific content contains the following two parts:1.By designing the introduction of long-chain carboxyl groups first,and then screening some substrates to synthesize luminescent groups,finally designing 11 new functional dyes of HX1-3,HQ1-4 and HY1-4 by simple and inexpensive synthesis method.The structures of 11 new compounds were characterized by 1H NMR,13 C NMR,HRMS(ESI),and IR.Their spectral properties were tested to prove that these 11 dyes have good light fastness and water solubility.The HX,HQ and HY series of fluorescence emission wavelengths are all around 600 nm,making them less photodamage to biological samples,and the background fluorescence interference of biomolecules is small;The Stokes shifts of the HX,HQ and HY series are around 70 nm,which makes them less error in fluorescence detection.It is known by acidity experiments that these 11 new dyes have good stability in vivo,indicating that they have certain application prospects in the analysis of biological macromolecules.2.The HQ and HY series of 8 new fluorescent dyes were applied to the labeling of glycoproteins.The dye/protein(D/P)labeling efficiency was between 1.5 and 1.9 and between 2.6 and 5.2,indicating that these dyes can better label the purified glycoprotein with its fluorescent signal by covalent coupling.Subsequently,the labeled glycoprotein was applied to the lectin chip to obtain a good effect,indicating that hat HQ and HY series fluorescent dyes can play a certain auxiliary role in the analysis of the changes of sugar chain binding sites and sugar chain species in proteins.