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• W3158600645 abstract "ConspectusDespite the fact that scanning electron microscopes (SEM) coupled with energy-dispersive X-ray microanalysis (EDS) has been commercially available for more than a half-century, SEM/EDS continues to develop and open new opportunities to study the morphology of advanced materials. This is particularly true in applications to hydrated soft matter. Developments in field-emission electron sources that enable low-voltage imaging of uncoated polymers, silicon-drift detectors that enable high-efficiency collection of X-rays characteristic of light elements, and cryogenic methods to effectively cryo-fix hydrated samples have opened new opportunities to apply techniques relatively well established in hard-materials applications to challenging new problems involving synthetic polymers. We have applied cryo-SEM imaging and spatially resolved EDS to collect new information characterizing polyelectrolyte microgels. These are charged gel particles with dimensions in the range of 0.1–100 μm. Perhaps most notable is the fact that the high hydration levels—the samples are mostly water—allow robust calibration curves to be generated using frozen-hydrated buffers with known salt and/or hydrocarbon compositions. Such calibration curves enable quantitative composition measurements in the low-concentration extremes associated with high-swelling hydrogels. We use an experimentally derived carbon calibration curve to determine the microgel swell ratio, Q. The swell ratio, arguably, is the single most important gel characteristic because it is directly related to the mesh size of the networked polymer, which in turn determines many of the gel’s mechanical and transport properties. While Q can be experimentally measured in macroscopic gels based on weight measurements in the dry and hydrated states, it is very difficult to measure in a microgel, and the fact that EDS in a cryo-SEM can determine Q from a single X-ray spectrum is significant. Furthermore, because of the electrostatic charge distributed along the polymer chains, the presence and concentration of counter-ions play a critical role in polyelectrolyte systems. While conceptually understood for decades, experimental measurements of counter-ion concentrations have been largely limited to a relatively small set of materials that involve macroscopic samples. By developing calibration curves from frozen-hydrated buffer of known ionic strength, we measure the concentration of Na counter-ions in microgels of poly(acrylic acid) (PAA) with a limit of detection of ∼0.014 M. Such measurements may help resolve some long-standing questions in polyelectrolyte science concerning counter-ion condensation. Even in the absence of a calibration curve, we show that spatially resolved X-ray spectroscopy can map the spatial distribution of a cationic oligopeptide complexed within a hydrated PAA microgel because of the nitrogen fingerprint that, albeit at very low concentration, is unique to the peptide. We look specifically at the case of a microgel with a so-called core–shell structure, where, again, the underlying polyelectrolyte science responsible for core–shell formation remains incompletely understood. These examples highlight how a modern cryo-SEM can be exploited to quantitatively characterize hydrated soft matter. The approach is almost certain to continue its development and impact as the base of experienced practitioners, the accessibility to well-configured microscopes, and the abundance of challenging problems involving hydrated soft matter all continue to grow." @default.
• W3158600645 created "2021-05-10" @default.
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• W3158600645 date "2021-05-04" @default.
• W3158600645 modified "2023-10-16" @default.
• W3158600645 title "Analytical Cryo-Scanning Electron Microscopy of Hydrated Polymers and Microgels" @default.
• W3158600645 cites W1487808887 @default.
• W3158600645 cites W1504193762 @default.
• W3158600645 cites W1879790803 @default.
• W3158600645 cites W1967542656 @default.
• W3158600645 cites W1970177880 @default.
• W3158600645 cites W1971722991 @default.
• W3158600645 cites W1980893130 @default.
• W3158600645 cites W1981268180 @default.
• W3158600645 cites W1981385996 @default.
• W3158600645 cites W1988813095 @default.
• W3158600645 cites W1991678456 @default.
• W3158600645 cites W1995785876 @default.
• W3158600645 cites W1998259906 @default.
• W3158600645 cites W2001881856 @default.
• W3158600645 cites W2002005365 @default.
• W3158600645 cites W2002899682 @default.
• W3158600645 cites W2007488754 @default.
• W3158600645 cites W2008009390 @default.
• W3158600645 cites W2008385258 @default.
• W3158600645 cites W2009268866 @default.
• W3158600645 cites W2010370589 @default.
• W3158600645 cites W2016482818 @default.
• W3158600645 cites W2027967940 @default.
• W3158600645 cites W2030431187 @default.
• W3158600645 cites W2032660624 @default.
• W3158600645 cites W2032865683 @default.
• W3158600645 cites W2039860382 @default.
• W3158600645 cites W2043369644 @default.
• W3158600645 cites W2044872440 @default.
• W3158600645 cites W2049335617 @default.
• W3158600645 cites W2054832203 @default.
• W3158600645 cites W2056126543 @default.
• W3158600645 cites W2056934481 @default.
• W3158600645 cites W2058949619 @default.
• W3158600645 cites W2058983707 @default.
• W3158600645 cites W2060812174 @default.
• W3158600645 cites W2062887854 @default.
• W3158600645 cites W2063306560 @default.
• W3158600645 cites W2064032645 @default.
• W3158600645 cites W2064858075 @default.
• W3158600645 cites W2068326208 @default.
• W3158600645 cites W2080323665 @default.
• W3158600645 cites W2082671408 @default.
• W3158600645 cites W2082783135 @default.
• W3158600645 cites W2083902817 @default.
• W3158600645 cites W208525513 @default.
• W3158600645 cites W2094766165 @default.
• W3158600645 cites W2099542679 @default.
• W3158600645 cites W2103972113 @default.
• W3158600645 cites W2117274978 @default.
• W3158600645 cites W2132153996 @default.
• W3158600645 cites W2153810072 @default.
• W3158600645 cites W2216718868 @default.
• W3158600645 cites W2219169508 @default.
• W3158600645 cites W2315121296 @default.
• W3158600645 cites W2322863941 @default.
• W3158600645 cites W2505396311 @default.
• W3158600645 cites W2560771283 @default.
• W3158600645 cites W2587701162 @default.
• W3158600645 cites W2599245673 @default.
• W3158600645 cites W2606251873 @default.
• W3158600645 cites W2620432867 @default.
• W3158600645 cites W2768290837 @default.
• W3158600645 cites W2772283214 @default.
• W3158600645 cites W2911620331 @default.
• W3158600645 cites W2912325502 @default.
• W3158600645 cites W2921725237 @default.
• W3158600645 cites W2951971540 @default.
• W3158600645 cites W2953611840 @default.
• W3158600645 cites W2964352702 @default.
• W3158600645 cites W2964430111 @default.
• W3158600645 cites W2995642626 @default.
• W3158600645 cites W3045894547 @default.
• W3158600645 cites W3048374572 @default.
• W3158600645 cites W3088604767 @default.
• W3158600645 cites W4231032259 @default.
• W3158600645 doi "https://doi.org/10.1021/acs.accounts.1c00109" @default.
• W3158600645 hasPubMedId "https://pubmed.ncbi.nlm.nih.gov/33944550" @default.
• W3158600645 hasPublicationYear "2021" @default.
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