The path toward Li-ion batteries with higher energy densities will likely involve use of thin lithium (Li)-metal anode (<50 µm thickness), whose cyclability today remains limited by dendrite formation and low coulombic efficiency (CE). Previous studies have shown that the solid–electrolyte interface (SEI) of the Li metal plays a crucial role in Li-electrodeposition and -stripping behavior. However, design rules for optimal SEIs are not well established. Here, using integrated experimental and modeling studies on a series of structurally similar SEI-modifying model compounds, we reveal the relationship between SEI compositions, Li deposition morphology, and CE and identify two key descriptors for the fraction of ionic compounds and compactness, leading to high-performance SEIs. We further demonstrate one of the longest cycle lives to date (350 cycles for 80% capacity retention) for a high specific-energy Li||LiCoO2 full cell (projected >350 watt hours [Wh]/kg) at practical current densities. Our results provide guidance for rational design of the SEI to further improve Li-metal anodes.

Efficient loading of drugs in novel delivery agents has the potential to substantially improve therapy by targeting the diseased tissue while avoiding unwanted side effects. Here we report a first systematic study of the loading mechanism of phenanthriplatin and its analogs into tobacco mosaic virus (TMV), previously used by our group as an efficient carrier for anticancer drug delivery. A detailed investigation of the preferential uptake of phenanthriplatin in its aquated form (~2000 molecules per TMV particle versus ~1000 for the chlorido form) is provided. Whereas the net charge of phenanthriplatin analogs and their ionic mobilities have no effect on loading, the reactivity of aqua phenanthriplatin with the glutamates, lining the interior walls of the channel of TMV, has a pronounced effect on its loading. MALDI-MS analysis along with NMR spectroscopic studies of a model reaction of hydroxy-phenanthriplatin with acetate establish the formation of stable covalent adducts. The increased number of heteroaromatic rings on the platinum ligand appears to enhance loading, possibly by stabilizing hydrophobic stacking interactions with TMV core components, specifically Pro102 and Thr103 residues neighboring Glu97 and Glu106 in the channel. Electron transfer dissociation-MS/MS fragmentation, a technique that can prevent mass condition-vulnerable modification of proteins, reveals that Glu97 preferentially participates over Glu106 in covalent bond formation to the platinum center.

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Current methods for detecting bacterial infections, such as culture and morphological analysis of bacterial colonies, are time and labor intensive. Through the direct detection of bacterial volatile organic compounds (VOCs), via surface enhanced Raman spectroscopy (SERS), we report here a reconfigurable assay for the identification and monitoring of bacteria. We demonstrate differentiation between highly clinically relevant organisms: Escherichia coli, Enterobacter cloacae, and Serratia marcescens. This is the first differentiation of bacteria via SERS of bacterial VOC signatures. The assay also detected as few as 10 CFU/ml of E. coli in under 12 hrs, and detected E. coli from whole human blood and human urine in 16 hrs at clinically relevant concentrations of 103 CFU/ml and 104 CFU/ml, respectively. In addition, the recent emergence of portable Raman spectrometers uniquely allows SERS to bring VOC detection to point‐of‐care settings for diagnosing bacterial infections.

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