Polystyrene latex particles modified at the surface with different hydrophilic functional groups were prepared by miniemulsion polymerization and used as controlling agents in the crystallization of zinc oxide from aqueous medium. The effects of the chemical nature of the surface functionalization and the latex concentration on the crystal growth, morphology, and crystalline structure of the resulting zinc oxide were analyzed. Micro- and submicrosized crystals with a broad variety of morphologies depending on the functionalization were obtained. Among the different latexes studied, the acrylic-acid-derived particles were shown to be a convenient system for further quantitative investigations. In this case, as the additive concentration increases, the length-to-width ratio (aspect ratio) of the crystals decreases systematically. Preferential adsorption of the latex particles onto the fast-growing faces {001} of ZnO is assumed to follow a Langmuir-type isotherm, and interaction of the adsorbed particles with the growth centers will reduce the growth rate in [001]. This leads to a quantitative relationship linking the aspect ratio to the latex concentration at constant diameter and surface chemistry of the latex. The dependence of the aspect ratio on charge density of the latex can also be modeled by an algorithm in which attractive forces between the latex particle and the ZnO surface are balanced against repulsive forces of an osmotic nature. The latter are associated with the confined volume between the crystal and latex particle surfaces.

Our previous study demonstrated berberine (BBR) and fluconazole (FLC) used concomitantly exhibited a synergism against FLC-resistant Candida albicans in vitro. We also suggested BBR played a major antifungal role in the synergism of FLC and BBR, while FLC increased intracellular BBR concentrations. Our following systematic structural modification and reconstruction of BBR core identified the novel scaffold of N-(2-(benzo[d][1,3]dioxol-5-yl)ethyl)-2-(substituted phenyl)acet-amide derivatives 7a-i, including B-7b and B-7d exhibiting remarkable synergistic antifungal activity and low cytotoxicity. Here, the study mainly investigated the synergistic activity of FLC and B-7b and the underlying mechanism. In vitro interaction of FLC and B-7b was investigated against 30 FLC-resistant clinical isolates of C. albicans and non-C. albicans species, including Candida tropicalis, Candida parapsilosis, Candida glabrata, Candida krusei and Cryptococcus neoformans. The potent synergistic activity of B-7b in combination with FLC against FLC-resistant C. albicans was found through the checkerboard microdilution assay. The findings of agar diffusion tests and time-kill curves confirmed its better synergism with FLC. And as expected, B-7b exhibited much lower cytotoxicity than BBR to human umbilical vein endothelial cells. In contrast to BBR, we found that endogenous ROS augmentation was not involved in the synergism of FLC and B-7b. According to the results from our present comparative proteomic study, it seemed that the disruption of protein folding and processing and the weakening of cells’ self-defensive ability contributed to the synergism of FLC and B-7b. Together, these results suggested novel scaffold BBR derivative B-7b could be a promising synergist in combination with FLC for the treatment of invasive fungal infections.

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A crosslinking core-shell structured polyacrylate emulsion polymer was synthesized by semi-batch seeded emulsion polymerization with methyl methacrylate and butyl acrylate as main monomers, and pentaerythritol tetraacrylate as a cross-linking agent. Chemical structure and micro morphology structure of the obtained polymer emulsion particles were characterized by Fourier transform infrared spectra (FTIR) and transmission electron microscope (TEM), respectively. Influences of cross-linking agent content on water resistance, thermal property, and mechanical property of the emulsion films were investigated. Compared to the film of the unmodified polyacrylate emulsion, water absorption capacity of modified polyacrylate emulsion film with 1.0% PET4A declined to 4.7%, tensile strength at break increased from 1.35MPa to 3.03MPa, and elongation at break increased to 171.7%; 5%,10% and 50% weight loss temperature of the modified emulsion increased 17°C,32°C and 45°C, respectively.

A series of cross-linking core-shell structured poly (n-butyl acrylate) /poly (methyl methacrylate-co-styrene) emulsion polymer were prepared by semi-batch seeded emulsion polymerization with pentaerythritol triacrylate (PETA) as a cross-linking agent. The emulsion polymers were characterized by Fourier transform infrared spectra (FTIR) and transmission electron microscope (TEM), respectively. The influences of cross-linking agent content on the water resistance and mechanical properties of the emulsion films were investigated. The films prepared by the emulsion polymer with the cross-linking agent exhibited excellent water resistance, and mechanical properties (tensile strength and flexility), resulting from the cross-linking structure of shell segments compared with that prepared without cross-linking agent. The film of the emulsion polymer with 1.0wt% cross-linking agent exhibited better comprehensive performance.