Tyndall National Institute, Lee Maltings, University College Cork, Cork, Ireland.
Phys Chem Chem Phys. 2010 Sep 14;12(34):10040-7. doi: 10.1039/c003323e. Epub 2010 Jun 10.
The behaviour of two biological macromolecules, bovine pancreatic insulin and hen-egg-white lysozyme (HEWL), at aqueous-organogel interfaces confined within an array of solid-state membrane micropores was investigated via cyclic voltammetry (CV). The behaviour observed is discussed in terms of possible charge transferring species and mass transport in the interfacial reaction. Comparison of CV results for HEWL, insulin, and the well-characterised model ion tetraethylammonium cation (TEA(+)) revealed that the biomacromolecules undergo an interfacial reaction comprising biomacromolecular adsorption and facilitated transfer of electrolyte anions from the organic phase to a protein layer on the aqueous side of the interface, whereas TEA(+) undergoes a simple ion transfer process. Evidence for biomacromolecular adsorption on the aqueous side of the micro-interfaces is provided by comparison of the CVs for TEA(+) ion transfer in the presence and absence of the biomacromolecules. Similar experiments in the presence of the low generation polypropylenimine tetraamine dendrimer, (DAB-AM-4), a smaller synthetic molecule, revealed it to be non-adsorbing. The behaviour of biological macromolecules at miniaturised aqueous-organogel interfaces involves adsorption on the aqueous side of the interface and transfer of organic phase electrolyte anions across the interface to associate with the adsorbed biomacromolecule. The data presented support the previously suggested mechanism for biomacromolecular voltammetry at liquid-liquid interfaces, involving adsorption and facilitated ion-transfer of organic electrolyte anions.
通过循环伏安法（CV）研究了两种生物大分子，牛胰腺胰岛素和鸡卵清溶菌酶（HEWL），在固体膜微孔阵列中受限的水-有机凝胶界面的行为。根据可能的电荷转移物种和界面反应中的质量传递，讨论了观察到的行为。将 HEWL、胰岛素和经过充分表征的模型离子四乙基铵阳离子（TEA(+)) 的 CV 结果进行比较，发现生物大分子经历了一个界面反应，包括生物大分子的吸附和从有机相到界面水侧的蛋白质层的电解质阴离子的促进转移，而 TEA(+) 则经历了简单的离子转移过程。通过比较 TEA(+)离子转移在存在和不存在生物大分子时的 CV，提供了生物大分子在微界面水侧吸附的证据。在低代聚丙亚胺四胺树枝状大分子（DAB-AM-4）存在的类似实验中，发现它是非吸附的。生物大分子在微型水-有机凝胶界面的行为涉及在界面的水侧吸附和有机相电解质阴离子穿过界面与吸附的生物大分子缔合的转移。所提出的数据支持了先前在液-液界面上生物大分子伏安法的建议机制，涉及有机电解质阴离子的吸附和促进离子转移。
