RESUMO
In this work,a highly sensitive electrochemical biosensor for the detection of trace adenosine triphosphate (ATP) was proposed.The biosensor was based on porous anodic alumina (PAA) and SiO2 nanoparticles combining with several oligonucleotides to construct sandwich structure.It was characterized by scanning electron microscopy,fluorescence microscopy,differential pulse voltammetry and electrochemical impedance spectroscopy,which conformed to the reliability of the biosensor fabrication and the feasibility of the detection.In the presence of ATP,the sandwich structures could be destroyed.The variation of the current was directly corresponding to the amount of the ATP.The application of SiO2nanoparticles could effectively reduce the background and increase the sensitivity of the biosensor.The calibration curve of ATP was obtained in the range of 0.025-0.900 nmol/L with the detection limit of 13 pmol/L (S/N=3).Also,the biosensor exhibited a good specificity.Besides,the sensor was constructed easily and possessed excellent regeneration ability.The proposed biosensor was applied in detection of real sample such as mice blood.Therefore,the proposed ATP-sensing biosensor could be expected to be applied in clinical,pharmaceutical and environmental detection.
