Signal Amplification By Strand Displacement In A Carbon Dot Based Fluorometric Assay For ATP

Adenosine triphosphate?ATP?is the center of chemical energy storage and metastasis in living organisms,and plays an important role in antiarrhythmia,micro-vascular dilatation and nerve signal protection,Increasing evidences have shown that fluctuation in ATP level is closely related to some diseases,such as anoxia,Parkinson's disease and some malignant tumors.Moreover,the viability and injury of cells can also be indicated by ATP.As a consequence,the accurate quantification of ATP has become the hot spot in biochemical analysis and clinical diagnosis.A fluorometric ATP assay is described that makes use of carbon dots and graphene oxide along with strand displacement reaction.In the absence of target,the fluorescence of carbon dots is strong and in the�on�state,because the signal probe hybridizes with the aptamer strand and cannot combine with grapheme oxide.In the presence of ATP,it will bind to the aptamer and induce a strand displacement reaction.Consequently,the signal probe is released,the sensing strategy will change into the�off�state with the addition of graphene oxide.This aptasensor exhibits selective and sensitive response to ATP with a linear range of 10-800 nmol L^-1 and allows a limit of detection as low as 3.3 nmol L^-1.In addition,this method has been successfully used to detect ATP in human serum with satisfactory results.