Luminescence-colour-changing sensing toward neurological drug carbamazepine in water and biofluids based on white light-emitting CD/Ln-MOF/PVA test papers

Abstract

Carbamazepine (CBZ) is usually used as a marker to reflect human health in biofluids and anthropogenic pollution in the aqueous system. However, few chemosensors sensitive enough to detect the allowable concentration of CBZ are available in practice. For this purpose, “luminescence-colour-changing sensing” test papers have been designed and prepared, exhibiting nanomolar limits of detection toward CBZ in water, urine, and serum. The systematic anchoring of yellow-light-emitting MOF-76 (Eu0.05Tb0.95) and blue-light-emitting carbon dots (CDs) on a polyvinyl alcohol (PVA) substrate, a white-light-emitting film (0.012CD/Eu0.05Tb0.95BTC/PVA) has been obtained by precise tuning of the component ratios. Through hydrogen bonding interactions, the luminophores (CD and Eu0.05Tb0.95BTC) show a uniform dispersibility on the PVA substrate, as well as advanced thermal, mechanical, environmental, and biochemical stability regarding their structure and photoluminescence. Benefiting from these beneficial photophysical properties and a powerful adsorption capacity, the 0.012CD/Eu0.05Tb0.95BTC/PVA film displays exceptional sensitivity toward nanomolar-level CBZ in water and biofluids (urine and serum), via a luminescence colour change from white to blue. The advances in stability, sensitivity, selectivity, and recyclability of the sensor reveal the promising potential of this portable, fast and accurate sensor in practice.