Investigation of interaction between boronic acids and sugar: effect of structural change of sugars on binding affinity using steady state and time resolved fluorescence spectroscopy and molecular docking

Abstract

Binding interactions of boronic acid derivatives viz. 2-Methylphenylboronic acid (B1) and 3-Methoxyphenylboronic acid (B2) with mono saccharides (arabinose, fructose and galactose) and disaccharides (sucrose, lactose and maltose) in aqueous condition at pH 7.4 by means of fluorescence spectroscopy is reported in the present investigation. Sugar sensing as well as continuous glucose monitoring (CGM) plays a significant role in diabetes regulation. Sugar sensors mediated through enzymes have their own drawbacks, which led to encouragement to search for designing new sensors through alternate approaches. Among many, fluorescence-based sensors are drawing more attention. Boronic acid-based fluorescence sensors have the capacity to bind reversibly with diols, which makes their demand high in applications. Addition of sugar reduces fluorescence intensities. Change in intensities is associated to cleavage of intermolecular hydrogen bonding which leads in reduced stability of boronate ester. Lineweaver-Burk and Benesi-Hildebrand equation is used for analysing data. Mono sugars are estimated to have higher binding constants. Mutarotation leads to structural changes in saccharides which play a key role in binding interactions. Sugars in furanose form are found to be highly favoured for binding. Molecular docking of B1 and B2 with proteins with PDB ID: 2IPL and 2IPM being periplasmic was done with the help of Schrodinger Maestro 11.2 version. GLIDE scores terms are used for expressing binding affinity.

Reusable Dual‐Photopolymerized Holographic Glucose Sensors

“…[ 29 ] 3‐AAPB is trigonal and can react with water to form an anionic tetrahedral boronate (Figure 1b). [ 30 ] 1,2 or 1,3 cis‐diols of carbohydrates act as Lewis bases which can bind with boronic acid to form a 5 or 6 membered cyclic boronate ester. [ 31 ] Boronic acids can bind through the trigonal and tetrahedral form, determined through several factors such as pH, temperature, and concentration.…”

“…[31] Boronic acids can bind through the trigonal and tetrahedral form, determined through several factors such as pH, temperature, and concentration. [30] DP HSs were generated by a 4-step fabrication process (Figure 1c). 1) A hot washed RM film was saturated with aerated IL monomer solutions and allowed to soak 5 min before 2) being dried for 10 min and 3) exposed to a coherent UV laser pulse, and finally 4) washed to remove unpolymerized material.…”

Thioflavin-modified molecularly imprinted hydrogel for fluorescent-based non-enzymatic glucose detection in wound exudate

“…As shown in Figure S 11, the fluorescence decreased only when treated with glucose and fructose, whereas an increase of the signal was observed with mannose and lactose confirming the improved selectivity of the proposed imprinted hydrogel. The association binding constant (Ka) was calculated from Lineweaver-Burk plots of glucose and fructose, for which the signal decreased linearly with the increase of analyte concentration (Figure S 12) [ 56 ]. The Ka between MIH_GSH and glucose was found to be 82.9 ​M -1 , more than 6-fold higher than the Ka calculated for NIH_GSH (13.1 ​M -1 ) confirming the improved affinity of glucose for the recognition boronic acid moieties when the latter is specifically oriented thank to the imprinting procedure.…”

A new fluorescent boronic acid sensor based on carbazole for glucose sensing via aggregation-induced emission

“…This pH-dependent property can influence the interaction of boronic acid group with monosaccharides. 23 Therefore, the influence of pH variations on CPBA fluorescence characteristics was examined. Fluorescent emission of CPBA and CPBA in the presence of fructose and glucose at different pH values showed an excimer emission development only for the adding glucose at pH values greater than 8.5, indicating the selectivity of the chemosensor toward glucose (Fig.…”