摘要
K＋存在时,富含鸟嘌呤（Guanine）的特定序列单链DNA会发生构象变化形成G-四联体结构,从而能够与氯化血红素（hemin）结合生成具有过氧化物酶活性的模拟酶,对鲁米诺-H2O2化学发光体系具有强的催化作用.据此,提出了利用G-四联体-hemin-鲁米诺-H2O2化学发光体系测定K＋的新方法.探讨了DNA浓度,hemin浓度,反应时间及干扰离子对化学发光体系的影响,在优化的实验条件下,对K＋检测的线性范围为2.8×10-5~1.5×10-4mol/L,检出限（3σ,n=11）为9.0×10-6mol/L.本方法用于环境水样中K＋检测,结果良好.
Single-strand DNA with G-rich sequences can fold into G-quadruplexes in the presence of K＋.The G-quadruplexes can bind hemin to form a kind of DNAzyme of peroxidase activity,which can catalyze the chemiluminescence reaction of luminol-H2O2.Based on this phenomenon,a novel method for K＋ detection is developed in this work.The experimental conditions have been investigated systematically,including the concentration of DNA and hemin,reaction time,and the interference ions.There was a good linear relationship between CL intensity and the concentration of K＋ in the range of 2.8×10-5~1.5×10-4mol/L with the detection limit（3σ,n=11） of 9.0×10-6 mol/L.The developed method has been applied to the determination of K＋ in the environmental water sample with satisfactory results.
出处
《河北大学学报（自然科学版）》
CAS
北大核心
2011年第2期167-170,共4页
Journal of Hebei University(Natural Science Edition)
基金
国家自然科学基金资助项目(20875021)
