摘要
噻唑橙(Thiazole orange,TO)在游离状态下几乎没有荧光,但当其与富G的DNA结合后,会产生很强的荧光增强效应。据此,利用TO识别有无钾离子存在时富G序列的构象变化,建立了一种基于核酸适体(Aptamer)构象效应进行钾离子检测的无标记荧光检测方法。在优化实验条件下,钾离子浓度在(1～60)×10-6mol/L和(4～9)×10-4mol/L范围内与荧光强度呈良好的线性关系,检出限(S/N=3)为2.2×10-7mol/L。对Li+、Na+、Ca2+、Mg2+、NH4+5种离子进行对照试验的结果表明,该方法不仅具有较好的灵敏度还具有较好的选择性,且无需对DNA进行标记,成本低,分析速度快。
Free thiazole orange is almost no fluorescent, but it shows high fluorescence when binding to G-rich DNA. Herein, a label-free fluorescent detection method for K^＋ was developed based on the recognition of conformation change of G-rich DNA in the absence and presence of K ^＋ . Under the optimum conditions, a good linear relationship between the fluorescence intensity and the potassium ion concentration was found in the range of （ 1 - 60） × 10^-5 mol/L and （4 -9） × 10^-4 mol/L. A sensitive detection limit of 2.2 x 10-7 mol/L was obtained. Control experiments with other ions, such as Li^＋ , Na^
＋ , Ca^2＋ , Mg^2＋ and NH4^＋ , showed this method not only possess good sensitivity and specificity, but also is label-free, simple and economical.
出处
《化学通报》
CAS
CSCD
北大核心
2013年第2期163-166,共4页
Chemistry
基金
国家自然科学基金项目(21104030)
山东省优秀中青年科学家科研奖励基金项目(BS2009SW040)
山东省自然科学基金项目(ZR2011BQ012)
环境化学与生态毒理学国家重点实验室开放基金项目(KF2011-27)
山东省高等学校科技计划项目(J11LB03)资助
关键词
核酸适体
噻唑橙
钾离子
荧光
Aptamer, Thiazole orange, Potassium ion, Fluorescence
