Key laboratory of Material Chemistry for Energy Conversion and Storage (Huazhong University of Science and Technology), Ministry of Education, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, 430074 Wuhan, China. Electronic address: [Email]
A kind of nitrogen doped carbon dots (NCDs) with excellent stable luminescence performance was prepared by pyrolysis using ethanolamine as precursor. By simply mixing solution of NCDs and calcein-Eu3+, a ratio fluorometric probe with carbon dots as "internal reference" and calcein-Eu3+ as recognition group was constructed for ATP detection. The fluorescence of the calcein can be selectively quenched by Eu3+, and can be restored when ATP was added because Eu3+ ions exhibit higher affinity to the oxygen-donor atoms originated from phosphates than that from carboxylate groups. Meanwhile, fluorescence of NCDs was not affected by Eu3+, calcein or ATP. By adding NCDs as "internal reference" in the above system, a new ratiometric strategy for detecting ATP was conducted. The dynamic linear range for ATP detection was 5.0 × 10-8 mol L-1~ 2.0 × 10-6 mol L-1, and the detection limit was 2.0 × 10-8 mol L-1.The method was successfully applied to detecting ATP in adenosine disodium triphosphate injection. Compared with calcein- Eu3+ probe without NCDs as reference, the ratio fluorometric probe effectively reduced interference and improved the accuracy and sensitivity.