Sensitive fluorescence detection of saliva pepsin by a supramolecular tandem assay enables the diagnosis of gastroesophageal reflux disease

Gastroesophageal reflux disease (GERD) is a prevalent gastrointestinal disorder with substantial morbidity. However, the reliable, non-invasive, and specific diagnosis of GERD remains a challenge due to the lack of specific symptoms and imaging features. Herein, we report a supramolecular tandem assay through using a reporter pair of sulfonatocalix[4]arene and lucigenin for the sensitive and real-time detection of saliva pepsin, an ideal biomarker for GERD. Moreover, we achieve the detection of pepsin in commercial artificial saliva, demonstrating the potential of this supramolecular approach for point-of-care testing of GERD.