Glycoprotein fluorescent speed sensing by newly-synthesized boronic complex probe and chip supramolecular electrophoresis

In this work, we proposed the concept of fluorescent speed sensing (FSS) of glycoprotein in chip supramolecular electrophoresis (CSE). To achieve a stable FSS run, we firstly synthesized a novel boronic acid-based diben-zoxanthene receptor (Rp3) by a simple one-pot reaction and the complex probe of F1@Rp3 containing Rp3 and fluorescein (F1), and performed a series of experiments to assess the complex probe's ability for recognition of saccharides and glycoproteins. Secondly, we revealed the mechanism of 'balance electromigration of supramolecular complex probe' in FSS and developed the relevant theory of FSS via a series of theoretical derivation. The FSS theory showed that the moving speed of F1 was a function of glycoprotein content, indicating a novel model of glycoprotein sensing. To demonstrate the validity and utility of developed model and theory, IgG and ovalbumin were selected as model glycoproteins for the relevant experiments. The results verified the validity of FSS concept to glycoprotein assay with good accuracy (less than 6.33 % difference from standard HPLC method), stability (less than 6.04 % RSD) and linearity (higher than R2 = 0.99) as well as fair sensitivity (8.48 ng). Finally, the FSS was successfully used for the analysis of HbA1c (a key biomarker in diabetes blood). The developed FSS concept and complex probe have great potential for glycoprotein sensing, particularly for the diagnosis of diabetes.