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Molecularly imprinted polymers (MIPs) are synthetic polymers that mimic the functions of antibodies. Though MIPs are promising tools in various areas, achieving high selectivity in MIPs can be difficult. To improve selectivity, various approaches have been implemented; however, the role of polymerization methods or synthetic techniques in enhancing the selectivity of MIPs has not been studied and remains a crucial area for further research. MIPs are typically prepared from free radical reactions. Recently, we found that Dielectric Barrier Discharge (DBD) plasma can be used to initiate the polymerization of vinyl monomers. The DBD plasma method allows the monomers to associate with the template molecules and initiate polymerization with minimal disruption to the positioning of the monomers. We hypothesize that this could be a preferred method to prepare MIPs over the traditional radical reaction that may cause a disturbance of the pre-associated monomers on the templates for the polymerization. Chicken egg white serum albumin (CESA) was used as the template protein for the MIPs. Our results show that in all test conditions, approximately twofold improvement in selectivity was achieved, which is the primary performance metric for MIPs. This enhancement was evident across all categories, including MIPs prepared from various monomer combinations. [ABSTRACT FROM AUTHOR]

We have investigated the structure and activity of electrocatalysts for the oxygen evolution reaction (OER) that had low loadings of Ir incorporated into the 2D layered MnO2, (birnessite, nominally δ‐MnO2) and the 3D MnO2 (pyrolusite, β‐MnO2). The Ir‐incorporated β‐MnO2 (Ir/β‐MnO2) electrocatalysts were prepared for the first time via a thermally induced phase transition of δ‐MnO2 containing 16–22 wt% Ir. This phase transition of δ‐MnO2 to β‐MnO2 was facilitated by the presence of Ir in the structure, as both Ir in IrO2 and Mn in β‐MnO2 could adopt a thermodynamically favored rutile structure. Extended X‐ray absorption fine structure (EXAFS) of Ir/β‐MnO2 showed that the catalyst consisted of Ir substituted into the crystalline β‐MnO2 lattice. 22 wt% Ir/β‐MnO2 (60 μgIrcmgeo-2 ${{\rm{{\rm \mu} g}}_{{\rm{Ir}}} \,{\rm{cm}}_{{\rm{geo}}}^{ - 2} }$) exhibited an OER overpotential (η ${\eta }$) of 337 mV, lower than the η ${\eta }$ for commercial IrO2. This η ${\eta }$ was constant for 6 h, at 10 mA cmgeo-2 ${{\rm{cm}}_{{\rm{geo}}}^{ - 2} }$ in 0.5 M H2SO4. EXAFS, high‐angle annular dark‐field scanning transmission electron microscopy (HAADF‐STEM) and X‐ray absorption near edge structure (XANES) showed that 22 wt% Ir/β‐MnO2 had a strained structure containing ∼41 % Mn3+, an OER active species, along with a modified Ir bond covalency consisting of both Ir−O−Ir and Ir−O−Mn. [ABSTRACT FROM AUTHOR]

Microcantilever sensor technology has been steadily growing for the last 15 years. While we have gained a great amount of knowledge in microcantilever bending due to surface stress changes, which is a unique property of microcantilever sensors, we are still in the early stages of understanding the fundamental surface chemistries of surface-stress-based microcantilever sensors. In general, increasing surface stress, which is caused by interactions on the microcantilever surfaces, would improve the S/N ratio and subsequently the sensitivity and reliability of microcantilever sensors. In this review, we will summarize (A) the conditions under which a large surface stress can readily be attained and (B) the strategies to increase surface stress in case a large surface stress cannot readily be reached. We will also discuss our perspectives on microcantilever sensors based on surface stress changes. 10.1021/ac901955d