Particle size measurements of cellulose nanocrystals (CNCs) are challenging due to their broad size distribution, irregular shape and propensity to agglomerate. Particle size is one of the key parameters that must be measured for quality control purposes and to differentiate materials with different properties. We report the results of an interlaboratory comparison (ILC) which examined atomic force microscopy (AFM) data acquisition and data analysis protocols. Samples of CNCs deposited on poly-Llysine coated mica were prepared in the pilot laboratory and sent to 10 participating laboratories including academic, government and industrial organizations with varying levels of experience with imaging CNCs. The participant data sets indicated that the central

Chitin nanofiber (ChNF) has received significant research attention owing to its potential for use in a variety of applications, such as medicine and cosmetics. Here, we synthesize a novel ChNF material, ChNF-coated polymer microparticles, using a Pickering emulsion-templated approach. Two varieties of ChNF with different crystal structures, lengths, and surface charges were used to form the microparticle shells. When ChNFs with a shorter length and greater surface charge were used, the microparticles showed good dispersibility in water and narrow size distribution with number-and volume-median diameters of 1.46 and 1.84 μm, respectively. The microparticles were easily collected by filtration and redispersed in water, even after drying. The surface ChNF shells assembled at the microparticle surfaces showed potential as an adsorption site, effectively capturing anionic dye molecules. This technique offers new opportunities for the development of green nanocomposite materials using a facile aqueous process.

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Chitin is a key component of hard parts in many organisms, but the biosynthesis of the two distinctive chitin allomorphs, α-and β-chitin, is not well-understood. The accurate determination of chitin allomorphs in natural biomaterials is vital. Many chitin-secreting living organisms, however, produce poorly crystalline chitin which leads to spectrums with only broad lines and imprecise peak positions under conventional analytical methods such as X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), and solid state nuclear magnetic resonance spectroscopy (NMR), resulting in inconclusive identification of chitin allomorphs. Here, we developed a novel method for discerning chitin allomorphs based on their different complexation capacity and guest selectivity, using ethylenediamine (EDA) as a complexing agent. From the peak shift observed in XRD profiles of the chitin/EDA complex, the chitin allomorphs can be clearly discerned. By testing this method on a series of samples with different chitin allomorphs and crystallinity, we show that the sensitivity is sufficiently high to detect the chitin allomorphs even in near-amorphous, very poorly crystalline samples. This is a powerful tool for determining the chitin allomorphs in phylogenetically important chitin-producing organisms and will pave the way to clarify the evolution and mechanism of chitin biosynthesis.