Application of Alizarin/Graphene-Chitosan Modified Electrode on Detection of Human Telomere DNA

A modified glassy carbon electrode of alizarin (AR) intermingled with graphene (CRG) and chitosan (CS) was prepared for the first time. The AR/CRG-CS electrode exhibited a pair of well-defined reversible redox peaks in 0. 1 mol/L phosphate buffer solution (PBS, pH 7. 4) with the oxidation peak potential of -0. 573 V and the reduction peak potential of -0. 652 V. It exhibited a two. proton and two-electron redox process and a fast heterogeneous electron transfer rate with the rate constant (K-s) of 1. 69 s(-1) using the cyclic voltammogram. Based on the characteristics of alizarin with the decreased current and negative potential after binding with human telomere DNA, a sensitive, simple, reliable and stable electrochemical method for the detection of alizarin using the AR/CRG-CS electrode was developed. The working curve was constructed in the range of 8x10(-8) -1. 4x10(-5) mol/L (R = 0. 9995) with the linear regression equation as Delta i(mu A)=8. 4860+0. 5366c (mu mol) and the detection limit (S/N) as 2x10(-8) mol/L.