中文摘要：

采用茜素（AR）掺杂石墨烯（CRG）、壳聚糖（CS）制备了AR/CRG-CS电极。该修饰电极在pH 7.4的PBS中出现了一对可逆的氧化还原峰,阳极峰的峰电位为＂0.573 V,阴极峰峰电位为＂0.652 V。通过循环伏安法（CV）证明AR在电极上发生了两电子两质子的氧化还原可逆过程,电子传递速率Ks为1.69 s＂1。基于AR与人类端粒DNA相互作用导致的AR峰电流减弱及式量电位（E0＇）负移的电化学信号,建立了一种灵敏简便、重现性好、稳定性好的测定人类端粒DNA的电化学方法,线性响应范围为8×10^-8～1.4×10^-5mol/L（R=0.9995）,线性回归方程为Δi（μA）=8.4860＋0.5366C（μmol/L）,检出限为2×10^-8mol/L（S/N=3）。

英文摘要：

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（Ks） of 1.69 s1 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 8×10^-8-1.4×10^-5 mol/L（R=0.9995） with the linear regression equation as Δi（μA）=8.4860＋0.5366c（μmol） and the detection limit（S/N） as 2×10^-8 mol/L.