Computational Model-Assisted Development of a Nonenzymatic\nFluorescent Glucose-Sensing Assay

Deep-red fluorescence\nwas implemented in this fully injectable,\nnonenzymatic glucose biosensor design to allow for better light penetration\nthrough the skin, particularly for darker skin tones. In this work,\na novel method was developed to synthesize Cy5.5 labeled mannose conjugates\n(Cy5.5-mannobiose, Cy5.5-mannotriose, and Cy5.5-mannotetraose) to\nact as the fluorescent competing ligand in a competitive binding assay\nwith the protein Concanavalin A acting as the recognition molecule.\nUsing fluorescence anisotropy (FA) data, a computational model was\ndeveloped to determine optimal concentration ratios of the assay components\nto allow for sensitive glucose measurements within the physiological\nrange. The model was experimentally validated by measuring the glucose\nresponse via FA of the three Cy5.5-labeled mannose conjugates synthesized\nwith Cy5.5-mannotetraose demonstrating the most sensitive response\nto glucose across the physiological range. The developed method may\nbe broadly applied to a vast range of commercially available fluorescent\ndyes and opens up opportunities for glucose measurements using nonenzymatic\nassays.