Tyndall National Institute, Lee Maltings, University College Cork, Cork, Ireland.
Anal Chem. 2010 Jan 1;82(1):258-64. doi: 10.1021/ac901909j.
The development of new methods for the detection of proteins and peptides is of widespread importance. In this work, the electrochemical behavior of peptide mixtures resulting from proteolytic digestion of proteins was investigated at the polarized liquid|liquid interface (or the interface between two immiscible electrolyte solutions, ITIES). The influence of pepsin digestion on three proteins (hemoglobin, lysozyme, and cytochrome c) was studied, and it was revealed that resulting cyclic voltammograms of the three protein digests were different due to the unique peptide mixtures for a given protein. Differential pulse stripping voltammetry of protein digests enabled the detection of digested proteins at concentrations ranging between 0.55 and 4.22 microM. A limit of detection of 0.55 microM of the initial concentration of protein was achieved, demonstrating the analytical possibilities of such an electrochemical method. These results show that ion-transfer voltammetry offers the opportunity to study and develop label-free detection of peptides resulting from enzymatic digestions of proteins and may thus have a role in development of new proteomic technologies.
新的蛋白质和肽检测方法的发展具有广泛的重要性。在这项工作中，在极化的液/液界面（或两种不混溶的电解质溶液之间的界面，ITIES）研究了蛋白质酶解产生的肽混合物的电化学行为。研究了胃蛋白酶消化对三种蛋白质（血红蛋白、溶菌酶和细胞色素 c）的影响，结果表明由于特定蛋白质的独特肽混合物，三种蛋白质消化物的循环伏安图不同。蛋白质消化物的差分脉冲剥离伏安法能够在 0.55 到 4.22 microM 的浓度范围内检测到消化的蛋白质。达到了初始蛋白质浓度 0.55 microM 的检测限，证明了这种电化学方法的分析可能性。这些结果表明，离子转移伏安法为研究和开发基于酶解蛋白质的肽的无标记检测提供了机会，因此可能在开发新的蛋白质组学技术方面发挥作用。
