Research On Sugars Recognition Using Novel Two-component Fluorescence Sensing System

As an essential molecule in biology,sugar is involved in many physiological processes,such as providing energy to cells,cell construction and molecular identification.In the living body,abnormal sugar metabolism could cause certain diseases,such as incurable diabetes and cancer.Therefore,the recognition of sugar is of great significance in related fields,such as biology and medicine.However,there are many reasons that make selective sugar recognition difficult,such as the polyhydroxy structure in sugar molecules,the solvation of monosaccharides in water,the difficulty in distinguishing water and hydroxyl groups in aqueous solutions,and the low selectivity of probes used to identify sugar.Studies have shown that boric acid can reversibly form a five-membered or six-membered cyclic ester with cis 1,2-or 1,3-diol at low concentration through covalent interaction.Boric acid can selectively recognize sugar,so sugar recognition system with high selectivity and high sensitivity can be developed based on boric acid.In recent years,many studies have focused on the development of single-component fluorescent sensors based on boric acid molecules to detect sugar molecules.Single component system was not sensitive and could not modify the structure of boric acid and fluorophore at the same time.In order to avoid this defect,this paper built a new type of two-component combination system for sugar recognition research.Five boric acid derivatives were prepared based on 4-pyridone.Through dynamic light scattering and solubility experiment screening,three boric acid derivatives were selected to form a twocomponent fluorescent sensing system with HPTS at a p H of 7.4 in phosphate buffer.The two-component system’s recognition of sugar was investigated by fluorescence spectroscopy.The results show that in the range of physiological glucose concentration,the optimal ratio of the combined system for glucose detection is 5b: HPTS = 6: 1;5b-o:HPTS = 8: 1,at this ratio glucose having the best linear response.Under the 365 nm ultraviolet lamp,the fluorescence changes of the system before and after recognition can be clearly observed by the naked eye.Subsequently,5b / HPTS was used to conduct a sensory study on the eight sugars,and the recognition ability of the sugars in order was:fructose > xylitol > melose > mannose > galactose > maltose ≈ glucose > lactose.The 5bm / HPTS was used to study the four kinds of sugar,and the recognition ability of the sugars in order was: fructose> melose > maltose > glucose.The recognition ability was consistent with the conclusion obtained by the 5b / HPTS system.The system has the strongest response to fructose.Based on this,a two-component system based on 5b-m /HPTS was developed,which can be used for fructose specific detection.The system has strong sensitivity and practical application value.