Establishment of a Novel DNAzyme Sensor for Detecting Lead in Blood

To develop a method for detecting lead in blood by a novel DNAzyme sensor(Pb dependent DNAzyme).Blood samples were pretreated by Triton X-100,Proteinase K,nitric acid and TCA in turn.After adjusting pH to neutral,pretreated blood sample was mixed with substrate strand and enzyme strand.Time-dependent fluorescent measurement at ex/em= 485/535 nm was immediately started.The rate of fluorescent enhancement was recorded and analyzed with concentration of lead in the sample.Calibration curve was linear to 2000nmol/L,with R2=0.9988.Limit of detection was 9.44nmol/L.Detection of two reference materials of blood lead showed ideal accuracy and imprecision.(RSD of the two reference materials were 4.99% and 1.35%).In four recovery studies,recoveries were target.A novel DNAzyme sensor for detecting lead in blood has been developed,which could be used in clinical detection.