Department of Chemistry and Institute for Soldier Nanotechnologies, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States.
J Am Chem Soc. 2021 Mar 24;143(11):4397-4404. doi: 10.1021/jacs.1c00683. Epub 2021 Mar 16.
Hydrogen peroxide is a dynamic signaling molecule in biological systems. We report herein a versatile double emulsion sensor that can detect femtomolar quantities of aqueous hydrogen peroxide. The mechanism responsible for this sensitivity is a peroxide induced change in double emulsion structure, which results in a modified directional emission from dyes dissolved in the high index organic phase. The morphology (structure) of the double emulsion is controlled via interfacial tensions and a methyltrioxorhenium catalyzed sulfide oxidation results in an enhancement of the surfactant effectiveness. The incipient polar sulfoxide induced decrease of the interfacial tension at the organic-water (O-W) interface results in an increased interfacial area between the organic phase and water and a diminished emission perpendicular to the supporting substrate. The modularity of our sensory system is demonstrated through cascade catalysis between methyltrioxorhenium and oxidase enzymes, with the latter producing hydrogen peroxide as a byproduct to enable for the selective and sensitive detection of molecular and ionic enzymatic substrates.
过氧化氢是生物系统中的一种动态信号分子。本文报道了一种多功能的双重乳液传感器，可检测痕量的水相过氧化氢。这种灵敏度的机制是过氧化物诱导的双重乳液结构变化，导致溶解在高折射率有机相中的染料的发射方向发生变化。双重乳液的形态（结构）通过界面张力控制，并且亚甲基三氧化铼催化的硫化物氧化导致表面活性剂的有效性增强。初始极性亚砜在有机-水（O-W）界面处引起的界面张力降低导致有机相与水之间的界面面积增加，并且与支撑衬底垂直的发射减少。我们的传感系统的模块化通过亚甲基三氧化铼和氧化酶之间的级联催化来证明，后者作为副产物产生过氧化氢，从而能够选择性和灵敏地检测分子和离子酶底物。
