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  1. Rationale

    Effective analytical techniques are needed to characterize lignin products for the generation of renewable carbon sources. Application of matrix‐assisted laser desorption/ionization (MALDI) in lignin analysis is limited because of poor ionization efficiency. In this study, we explored the potential of cationization along with a 2,5‐dihydroxyacetophenone (DHAP) matrix to characterize model lignin oligomers.


    Synthesized lignin oligomers were analyzed using the developed MALDI method. Two matrix systems, DHAP and α‐cyano‐4‐hydroxycinnamic acid (CHCA), and three cations (lithium, sodium, silver) were evaluated using a Bruker UltraFlextreme time‐of‐flight mass spectrometer. Instrumental parameters, cation concentration, matrix, sample concentrations, and sample spotting protocols were optimized for improved results.


    The DHAP/Li+combination was effective for dimer analysis as lithium adducts. Spectra from DHP and ferric chloride oligomers showed improved signal intensities up to decamers (m/z1823 for the FeCl3system) and provided insights into differences in the oligomerization mechanism. Spectra from a mixed DHP oligomer system containing H, G, and S units showed contributions from all monolignols within an oligomer level (e.g. tetramer level).


    The DHAP/Li+method presented in this work shows promise to be an effective analytical tool for lignin analysis by MALDI and may provide a tool to assess lignin break‐down efforts facilitating renewable products from lignin.

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  2. null (Ed.)
    Abstract Advantages of polymeric nanoparticles as drug delivery systems include controlled release, enhanced drug stability and bioavailability, and specific tissue targeting. Nanoparticle properties such as hydrophobicity, size, and charge, mucoadhesion, and surface ligands, as well as administration route and suspension media affect their ability to overcome ocular barriers and distribute in the eye, and must be carefully designed for specific target tissues and ocular diseases. This review seeks to discuss the available literature on the biodistribution of polymeric nanoparticles and discuss the effects of nanoparticle composition and administration method on their ocular penetration, distribution, elimination, toxicity, and efficacy, with potential impact on clinical applications. 
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  3. Graphical abstract [Formula: see text] 
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  4. null (Ed.)
    Polymeric nanoparticles represent one major class of nanomaterials that has been proposed to improve the sustainability of agricultural operations by delivering organic agrochemicals such as pesticides more efficiently. Polymeric nanoparticles can improve efficiency through improved targeting and uptake, slow release, and lower losses of the chemicals, while also conferring the benefits of biodegradability and biocompatibility. This review provides a tutorial to environmental nanotechnology researchers interested in initiating research on the development and application of polymeric nanocarriers for delivery of agrochemicals, including pesticides and growth promoters for crops and antibiotics for livestock. In particular, this review covers the wider suite of methods that will be required beyond those typically used for inorganic metal or metal oxide nanoparticles, including synthesis of custom polymeric nanocarriers and characterization and tuning of agrochemical loading and release profiles. Benefits of polymeric nanocarriers are then discussed in terms of the physicochemical properties and fate and transport behaviors that contribute to higher efficiency and lesser environmental impacts compared to traditional (non-nano) formulations. Finally, opportunities for environmental nanotechnology researchers to collaborate with material scientists, microbiologists, and agricultural scientists to optimize the development of polymeric nanocarriers for agriculture are discussed. 
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