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

Abstract

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.