武丽娟, 王建秀, 李凯, 徐茂田. 电化学脱附与荧光技术联用检测表面固定生物分子中的半胱氨酸残基J. 药学学报, 2008, 43(1): 86-90.
引用本文: 武丽娟, 王建秀, 李凯, 徐茂田. 电化学脱附与荧光技术联用检测表面固定生物分子中的半胱氨酸残基J. 药学学报, 2008, 43(1): 86-90.
WU Li-juan, WANG Jian-xiu, LI Kai, XU Mao-tian. Determination of the cysteine residues in the surface-confined biomolecules by using electrochemical desorption and fluorescence detectionJ. Acta Pharmaceutica Sinica, 2008, 43(1): 86-90.
Citation: WU Li-juan, WANG Jian-xiu, LI Kai, XU Mao-tian. Determination of the cysteine residues in the surface-confined biomolecules by using electrochemical desorption and fluorescence detectionJ. Acta Pharmaceutica Sinica, 2008, 43(1): 86-90.

电化学脱附与荧光技术联用检测表面固定生物分子中的半胱氨酸残基

Determination of the cysteine residues in the surface-confined biomolecules by using electrochemical desorption and fluorescence detection

  • 摘要: 建立了一种检测表面固定的多肽以及DNA的方法。以还原型谷胱甘肽GSH为模型,将其固定在烷基硫醇自组装膜修饰的金电极表面,通过荧光试剂N-(9-吖啶)马来酰亚胺与游离巯基反应原位标记GSH,恒电位条件下脱附电极表面吸附物,检测脱附物在0.1 mol·L-1 KOH溶液中的荧光强度。GSH的检测限为40 pmol·L-1。该方法可扩展到检测电极表面固定的六肽FT(含3个半胱氨酸残基),脱附物的荧光强度约为GSH的3倍,和FT与GSH中半胱氨酸残基的数量比相吻合。此外,采用该方法对表面固定的DNA进行了序列特异性分析,结果满意。电化学脱附与荧光检测联用的方法灵敏度高、重现性好、样品用量少、快速准确。

     

    Abstract: To develop a method for the detection of surface-confined peptides containing cysteine residues or oligodeoxynucleotides (ODNs) whose 3′ ends modified with thiol groups, and a thiol-specific fluorescent cross-linker, N-(9-acridinyl)maleimide (NAM) was used. The peptides studied herein include both the oxidized and reduced forms of glutathione, and a hexapeptide (FT). Peptides are first attached onto the activated 11-mercaptoundecanoic acid (MUA)-terminated alkanethiol self-assembled monolayers (SAMs) and then derivatized with NAM. The cysteine residues was determined by using electrochemical desorption and fluorescence detection. GSH concentration as low as 40 pmol·L-1 can be measured. The fluorescence intensity in the case of FT is about 3 times as high as that for GSH, which is consistent with the molar ratio of cysteine residues in these two molecules. The analytical performance of gene analysis was also evaluated through the analyses of a complementary target and targets with varying numbers of mismatching bases. The method described here is simple, sensitive, reproducible, and does not require sophisticated analytical instrumentation and separation procedures.

     

/

返回文章
返回