Insulator-on-Conductor Fouling Amplifies Aqueous Electrolysis Rates.

The chemical industry is a major consumer of fossil fuels. Several chemical reactions of practical value proceed with the gain or loss of electrons, opening a path to integrate renewable electricity into chemical manufacturing. However, most organic molecules have low aqueous solubility, causing green and cheap electricity-driven reactions to suffer from intrinsically low reaction rates in industry's solvent of choice: water. Here, we show that a strategic, partial electrode fouling with hydrophobic insulators (oils and plastics) offsets kinetic limitations caused by poor reactant solubility, opening a new path for the direct integration of renewable electricity into the production of commodity chemicals. Through electrochemiluminescence microscopy, we reveal for the oxidation of organic reactants up to 6-fold reaction rate increase at the "fouled" oil-electrolyte-electrode interface relative to clean electrolyte-electrode areas. Analogously, electrodes partially masked (fouled) with plastic patterns, deposited either photolithographically (photoresists) or manually (inexpensive household glues and sealants), outperform clean electrodes. The effect is not limited to reactants of limited water solubility, and, for example, net gold electrodeposition rates are up to 22% larger at fouled than clean electrodes. In a system involving a surface-active reactant, rate augmentation is driven by the synergy between insulator-confined reactant enrichment and insulator-induced current crowding, whereas only the latter and possibly localized decrease in iR drop near the insulator are relevant in a system composed of non-surface-active species. Our counterintuitive electrode design enhances electrolysis rates despite the diminished area of intimate electrolyte-electrode contact and introduces a new path for upscaling aqueous electrochemical processes.

Tool to Resolve Distortions in Elemental and Isotopic Imaging.

Nanoscale secondary ion mass spectrometry (NanoSIMS) makes it possible to visualize elements and isotopes in a wide range of samples at a high resolution. However, the fidelity and quality of NanoSIMS images often suffer from distortions because of a requirement to acquire and integrate multiple image frames. We developed an optical flow-based algorithm tool, NanoSIMS Stabilizer, for all-channel postacquisition registration of images. The NanoSIMS Stabilizer effectively deals with the distortions and artifacts, resulting in a high-resolution visualization of isotope and element distribution. It is open source with an easy-to-use ImageJ plugin and is accompanied by a Python version with GPU acceleration.

Protocol for delivery of intraoperative immunotherapy to mice by surgical debulking of subcutaneous tumors.

Pre-clinical studies developing novel therapies to prevent cancer recurrence require appropriate surgical models. Here, we present a protocol for surgical debulking of subcutaneous tumors in mice, which allows for intraoperative application of immunotherapy-loaded biomaterials. We describe steps for inoculating tumor cells, anesthetizing mice, and performing surgery. We then detail procedures for applying biomaterial, bandaging mice, and data collection and analysis. The optimized bandaging regimen resolves the issue of wound dehiscence after surgery, for C57BL/6 mice, which interfere with surgical sites. For complete details on the use and execution of this protocol, please refer to Rwandamuriye et al.1.