Encapsulating Subsite Analogues of the [FeFe]-Hydrogenases in Micelles Enables Direct Water Interactions

详细信息    查看全文

• 作者：Robby Fritzsch ; Owen Brady ; Elaine Adair ; Joseph A. Wright ; Christopher J. Pickett ; Neil T. Hunt
• 刊名：The Journal of Physical Chemistry Letters
• 出版年：2016
• 出版时间：July 21, 2016
• 年：2016
• 卷：7
• 期：14
• 页码：2838-2843
• 全文大小：435K
• 年卷期：0
• ISSN：1948-7185

文摘

Encapsulation of subsite analogues of the [FeFe]-hydrogenase enzymes in supramolecular structures has been shown to dramatically increase their catalytic ability, but the molecular basis for this enhancement remains unclear. We report the results of experiments employing infrared absorption, ultrafast infrared pump–probe, and 2D-IR spectroscopy to investigate the molecular environment of Fe₂(pdt)(CO)₆ (pdt: propanedithiolate) [1] encapsulated in the dispersed alkane phase of a heptane–dodecyltrimethylammonium bromide–water microemulsion. It is demonstrated that 1 is partitioned between two molecular environments, one that closely resembles bulk heptane solution and a second that features direct hydrogen-bonding interactions with water molecules that penetrate the surfactant shell. Our results demonstrate that the extent of water access to the normally water-insoluble subsite analogue 1 can be tuned with micelle size, while IR spectroscopy provides a straightforward tool that can be used to measure and fine-tune the chemical environment of catalyst species in self-assembled structures.