Indicator Displacement Assay inside Dye-Functionalized Covalent Organic Framework for Ultrasensitive Monitoring Sialic Acid, an Ovarian Cancer Biomarker

Identifying biomolecules for disease diagnosis requires simple, accurate and reliable analytical techniques. Multiple signal transduction pathways have promoted the development of various biological analysis systems. However, most systems are largely limited by single mechanism or model analysis, which can easily lead to false positive/negative results. Herein, we report COF (TpPa-1) functionalized with dye (fluorescein sodium) and design this hybrid material (TpPa-1@Dye) to fabricate hydrogel for subsequent analysis with indicator-displacement assay (IDA) method. Selecting suitable metal cation (Cr3+) for the preparation of hydrogel can reduce the fluorescence of background, improve detection sensitivity and increase the corresponding sensing selectivity. The function of TpPa-1@Dye is an indicator in IDA-in-COF system, Cr3+ is a receptor of the analyte (sialic acid (SA), a biomarker for ovarian cancer diagnosis). Based on the above studies, the integrative logic operations (AND+IMP) are further establish...