Synthesis and also Chiroptical Properties regarding Planar Chiral Azahelicenes Depending on 22Paracyclophane

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Defibrillation of bacterial cellulose by ultra-refining was efficient to release nanofibers (BCNF) which were spray dried with the matrices formers mannitol (MN), maltodextrin or hydroxypropylmethylcellulose. The best microsystem comprised the association of BCNF and MN, so the selected microparticles were loaded with diclofenac sodium or caffeine. Depending on the proportion of BCNF, the nanofibers collapse promoted by spray drying can occur onto surface or into microparticles core, leading to different release behaviors. Samples showed pH-dependent drug release, so the microsystem developed with the lowest BCNF concentration showed important trend to gastroresistance. Caffeine was spray dried as a free drug and for this reason it was devoid of any control over release rates. The set of results showed BCNF can be considered an interesting and potential pharmaceutical excipient for lipophilic drugs. Beyond that, BCNF association with MN can lead to novel enteric drug delivery systems based on natural polymers.Fucoidan, a type of sulfated polysaccharide known for its anticoagulant, anti-tumor and anti-inflammatory effects, has been reported to have strong affinity towards P-selectin. P-selectin, which plays an important role in metastasis by enhancing the adhesion of cancer cells to endothelium and activated platelets in distant organs, is overexpressed on many cancer types. This study demonstrates the synthesis of a fucoidan-based drug delivery system for minimizing the side effects of doxorubicin (Dox) with the help of active targeting toward P-selectin. Fucoidan-doxorubicin nanoparticles (FU-Dox NPs), developed by direct conjugation of Dox to the fucoidan backbone, showed a well-controlled size distribution and sustained release. The active targeting capability of FU-Dox NPs toward P-selectin resulted in enhanced cellular uptake and cytotoxicity against the MDA-MB-231 cell line with high P-selectin expression compared to the MDA-MB-468 cell line with low P-selectin expression.Polyethylene glycol (PEG)-based composite phase change materials (PCMs) containing hydroxylated boron nitride (BN-OH), cellulose nanofiber (CNF), and chitosan (CS) were prepared by the method of interfacial polyelectrolyte complex spinning, based on in-situ ionic cross-linking between CNF and CS. The wrapping effect of cross-linked CNF/CS networks and the strong interfacial interactions contributed to superior shape-stability throughout the phase change process. Furthermore, the homogeneously dispersed BN-OHs was beneficial to the construction of the continuous thermal conductive paths, and the excellent interfacial interactions between BN-OH and the matrix would lower the heat loss caused by phonon scattering in the interface. #link# As a result, the thermal conductivity of the PCMs containing 47.5 wt% BN-OH reached 4.005 W/mK, which was 22.56 times higher than that of the pure PEG. Combined with the excellent thermal reliability and thermal stability, the form-stable PCMs showed a promising application potential in the fields of electronic cooling or temperature-adaptable textiles.Tunicate cellulose, extracted from the marine animal, has drawn increasing attention as the high crystallinity and aspect ratio. However, it is hard to prepare tunicate cellulose nanocrystals (tCNCs) with narrow size distribution in the traditional way, especially for the carboxylated samples, which also affects their lyotropic liquid crystal behavior to a certain extent. Herein, carboxylated tCNCs with uniform nanoscale dimensions and high surface charges density were prepared through ammonium persulfate (APS) oxidation and ultrasonic post-processing. Of particular interest, the formation of carboxylated tCNCs lyotropic chiral nematic liquid crystals was observed for the first time, which displayed obvious birefringence and fingerprint texture. Meanwhile, it was found that the critical concentration of phase separation for tCNCs suspension was around 3.5 wt% from the phase diagram. This study provides an efficient way to fabricate carboxylated tCNCs, and the self-assembly properties may lead to great potential applications in constructing advanced functional materials.Hydrogels have a complex, heterogeneous structure and organisation, making them promising candidates for advanced structural and cosmetics applications. Starch is an attractive material for producing hydrogels due to its low cost and biocompatibility, but the structural dynamics of polymer chains within starch hydrogels are not well understood, limiting their development and utilisation. We employed a range of NMR methodologies (CPSP/MAS, HR-MAS, HPDEC and WPT-CP) to probe the molecular mobility and water dynamics within starch hydrogels featuring a wide range of physical properties. The insights from these methods were related to bulk rheological, thermal (DSC) and crystalline (PXRD) properties. We have reported for the first time the presence of highly dynamic starch chains, behaving as solvated moieties existing in the liquid component of hydrogel systems. We have correlated the chains' degree of structural mobility with macroscopic properties of the bulk systems, providing new insights into the structure-function relationships governing hydrogel assemblies.Controlling the filtration of water-based drilling fluid effectively in high temperature environment is a great challenge in drilling engineering. In this study, β-cyclodextrin polymer microspheres (β-CDPMs) were synthesized by crosslinking between β-cyclodextrin and epichlorohydrin via inverse emulsion polymerization and employed as filtration reducers. The standard American Petroleum Institute filtration test showed that the β-CDPMs can only perform the enhanced filtration control ability at temperatures above 160 °C, and can tolerate the temperature resistance up to 240 °C without significant influence of rheology. As the thermal aging temperature is above 160 °C, numerous nano carbon spheres and nanostructured composites generated due to the occurrence of hydrothermal reaction. These high temperature stable nanoparticles bridged across the nano sized gaps and participated into forming dense filter cake, contributing to excellent filtration control. Ceritinib order proposed in this study opened a novel avenue for high temperature filtration control in water-based drilling fluids.