Doxorubicin is a common chemotherapeutic drug used to treat a variety of cancers. Monitoring the concentration of doxorubicin in human biological fluids is vital for treatment. In this work, we report an aptamer-functionalized, 808 nm-excited core-shell upconversion fluorescence sensor for specific detection of doxorubicin (DOX). Upconversion nanoparticles and DOX are used as energy donors and energy acceptors respectively. Aptamers immobilized on the surface of upconversion nanoparticles act as the molecular recognition element for DOX. The binding of DOX to the immobilized aptamers results in the fluorescence quenching of the upconversion nanoparticles via a fluorescence resonance energy transfer process. The relative fluorescence intensity exhibits a good linear response to DOX concentration in the range of 0.5 μM to 55 μM with a detection limit of 0.5 μM. The aptasensor displays high specificity and anti-interference against other antibiotics, common ions, and biomolecules owing to strong and specific interactions of aptamers towards DOX. The sensor is further applied for the detection of DOX in urine with spike recoveries of nearly 100%.
Keywords: 808 nm-excited upconversion nanoparticles; Aptamers; Doxorubicin; Fluorescence sensors.
© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.