Ratiometric fluorescence probe constructed using metal–organic frameworks and nitrogen-doped carbon dots for specific detection of adenosine monophosphate

The selective detection of adenosine monophosphate (AMP) is of great significance for the study of cellular energy metabolism. In this study, a ratiometric fluorescent probe was designed based on europium-based metal–organic frameworks (Eu-MOF) and nitrogen-doped carbon dots (CDs) that could specifically recognize AMP. Europium nitrate and Disodium Terephthalate (Na2BDC) were used to synthesize Eu-BDC with red fluorescence. The fluorescence of the Eu-BDC was effectively suppressed due to water molecules coordinating with the Eu3+. However, the addition of AMP resulted in a significant restoration of the fluorescence of Eu-BDC, while the fluorescence remained suppressed upon addition of adenosine diphosphate (ADP) and adenosine triphosphate (ATP). We developed a ratiometric fluorescence sensor that could accurately detect AMP by utilizing the blue fluorescence emitted from CDs as a reliable reference signal. Under optimal conditions, the Eu-BDC/CDs system for AMP detection exhibited a linear detection range of 1.0–80.0 μmol/L and a low limit of detection (LOD) of 0.25 μmol/L. The method displayed simple preparation, high selectivity and low cost for AMP detection. To our knowledge, this is the first highly-specify double-response biosensor for AMP.