A sensitive and cost-effective "turn-on" aptasensor for carcinoembryonic antigen using Ce-UiO-66 as an ultraefficient...

Carcinoembryonic antigen (CEA) is a key tumor biomarker, and its sensitive detection is critical for early diagnosis and treatment monitoring. This work presents a novel "turn-on" fluorescent aptasensor for sensitive and cost-effective detection of CEA, based on a FAM-labeled CEA aptamer (FAM-Aptamer) as the recognition unit, and Ce-UiO-66 nanoparticles as an efficient quenching platform. The Ce-UiO-66 material was synthesized and comprehensively characterized by SEM, TEM, XPS, FT-IR, Raman and XRD, demonstrating a high quenching efficiency (QE) of 99.95% toward the fluorescent aptamer. This exceptional quenching performance is attributed to a synergistic mechanism involving FRET, PET, DQE and SQE. After systematic optimization of key parameters (Ce-UiO-66 concentration: 66.67 µg/mL; quenching time: 30 min; pH: 7.6; incubation temperature: 25 ℃; incubation time: 60 min), the aptasensor achieved a wide dual-linear response across 1-10 ng/mL and 10-100 ng/mL, respectively, with a detection limit of 13.78 pg/mL. Validation in diluted serum samples confirmed its accuracy and precision for CEA quantification, with recoveries of 95.50-109.60% and RSDs below 5.07%. The proposed aptasensor provides a reliable, cost-effective, and sensitive platform for CEA detection, serving as a proof-of-concept biosensing platform, with a certain potential for clinical application.