Polyvinylidene fluoride (PVDF)-oxidized carbon nanotubes (OMWCNTs), PVDF-graphene oxide (GO) and PVDF-OMWCNTs-GO composite ultrafiltration membranes were prepared by solution-blending the ternary mixture of PVDF-oxidized low-dimensional carbon nanomaterials-dimethylacetamide in combination with the phase inversion method. The microscope images of the PVDF matrix microstructure showed that the composite membranes exhibited a bigger mean pore size and higher roughness parameters than pristine membranes. The contact angle of the membranes decreased from 78.5 (PVDF) to 66.8 (PVDF-OMWCNTs), 66.4 (PVDF-GO) and 48.5 (PVDF-OMWCNTs-GO). For the PVDF-OMWCNTs, PVDF-GO and PVDF-OMWCNTs-GO composite membranes, there was a 99.33%, 173.03% and 240.03% increase in permeation flux and a 21.71%, 17.23% and 14.29% increase in bovine serum albumin (BSA) rejection, respectively, compared with those of the pristine membranes.The newly developed composite ultrafiltration membranes demonstrate an impressive prospect for the anti-irreversible fouling performance in multi-cycle operations from BSA treatment. Additionally, the addition of OMWCNTs and GO increased the tensile strength of composite membranes from 1.866 MPa to 2.106 MPa and 2.686 MPa, respectively. Conspicuously, the PVDF composite ultrafiltration membranes endowed with oxidized low-dimensional carbon nanomaterials demonstrated fascinating hydrophilicity, permeability, antifouling and mechanical performance and promising application prospects owing to the rich oxygen-containing functional groups, high specific surface and synergistic effect of inorganic additive.

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Dynamin 1 (dyn1) is required for clathrin-mediated endocytosis in most secretory (neuronal and neuroendocrine) cells. There are two modes of Ca 2ϩ -dependent catecholamine release from single dense-core vesicles: full-quantal (quantal) and subquantal in adrenal chromaffin cells, but their relative occurrences and impacts on total secretion remain unclear. To address this fundamental question in neurotransmission area using both sexes of animals, here we report the following: (1) dyn1-KO increased quantal size (QS, but not vesicle size/content) by Ն250% in dyn1-KO mice; (2) the KO-increased QS was rescued by dyn1 (but not its deficient mutant or dyn2); (3) the ratio of quantal versus subquantal events was increased by KO; (4) following a release event, more protein contents were retained in WT versus KO vesicles; and (5) the fusion pore size (d p ) was increased from Յ9 to Ն9 nm by KO. Therefore, Ca 2ϩ -induced exocytosis is generally a subquantal release in sympathetic adrenal chromaffin cells, implying that neurotransmitter release is generally regulated by dynamin in neuronal cells. Ca 2ϩ -dependent neurotransmitter release from a single vesicle is the primary event in all neurotransmission, including synaptic/ neuroendocrine forms. To determine whether Ca 2ϩ -dependent vesicular neurotransmitter release is "all-or-none" (quantal), we provide compelling evidence that most Ca 2ϩ -induced secretory events occur via the subquantal mode in native adrenal chromaffin cells. This subquantal release mode is promoted by dynamin 1, which is universally required for most secretory cells, including neurons and neuroendocrine cells. The present work with dyn1-KO mice further confirms that Ca 2ϩ -dependent transmitter release is mainly via subquantal mode, suggesting that subquantal release could be also important in other types of cells.