Renal tubular-cell specific functions of HK-2 and MDCK renal tubular cells cultured on various membranes.

<p>γ-glutamyltransferase activity (A), alkaline phosphatase activity (B), and Mrp2 activity (C) are presented as means ± SD of three measurements. # and * represent significant differences (p<0.05) compared to the respective control on well bottom surfaces (WBS).</p

Cell proliferation on various membranes.

<p>Well bottom surfaces (WBS) were used as controls.</p

Liver-specific functions of rat hepatocytes and HepG2 cultured on various membranes.

<p>Urea production (A), albumin secretion (B), cytochrome P450 (CYP) 1A2 activity (C), and CYP 3A activity (D) are presented as means ± SD of three measurements. # and * represent significant differences (p<0.05) compared to the respective control on well bottom surfaces (WBS).</p

RT-PCR analysis for cell expression of genes coding for integrin β1 (<i>ITGB1</i>) and E-cadherin (<i>CDH1</i>) on various membranes and well bottom surfaces (WBS).

<p><i>GAPDH</i> was used as housekeeping gene, and its expression served as control.</p

Ultrastructure of HepG2 and HK-2 cells cultured for 144 h on F127 membrane.

<p>nuclear (N), mitochondria (M), lipid droplet (L), glycogen particle (Gly), bile duct (BD), microvillus (Mic).</p

Morphology of HK-2, MDCK, and HepG2 cell lines and rat hepatocytes cultured for 144 h on various membranes.

<p>Cell images were detected by scanning electron microscope. Scale bar represents 50 µm.</p

Cell attachment 4 h after seeding.

<p>A: in 10% FBS medium; B: in protein-free medium. Well bottom surfaces (WBS) were used as controls.</p

Formation of casting solutions of membranes.

<p>Formation of casting solutions of membranes.</p

Amphiphilic Interlayer Regulated Interfacial Polymerization for Constructing Polyamide Nanofiltration Membranes with High Perm-Selectivity of Mono-/Divalent Salts

High-quality thin-film composite (TFC) membranes with high selectivity and permeability have great significance owing to their practical applications, specifically for the accurate differentiation of monovalent and divalent ions. However, the trade-off effect between selectivity and permeability is still a big challenge due to the difficult structure adjustment of the selective layer. Herein, polydopamine (PDA) functionalized with a hydrophobic long alkane chain was first explored as a functional amphiphilic interlayer to synthesize high-quality TFC membranes via a confined interfacial polymerization (IP) reaction. The amphiphilic interlayer not only restricted the formation of the polyamide (PA) matrix in the pores of the substrate but also accelerated spatially more homogeneous polymerization and formed a PA active layer with a more uniform pore size distribution. The method may provide an effective principle for the construction of versatile polyamide-based membranes with high perm-selectivity on various supports. The NaCl/Na2SO4 separation factor of the D-8/PA membrane reached as high as 204.07, while the flux increased up to 25.71 L m–2 h–1 bar–1. This progress provides a more feasible way for the construction of high-quality TFC membranes with a devisable and creative amphiphilic interlayer for industrial application

Heat-Treated Polyacrylonitrile (PAN) Hollow Fiber Structured Packings in Isopropanol (IPA)/Water Distillation with Improved Thermal and Chemical Stability

In this study, polyacrylonitrile (PAN) hollow fiber membrane (HFM) was heat-treated by muffle furnace to strengthen the thermal and chemical stability. Membrane morphology with different materials was characterized by scanning electron microscopy (SEM). It has shown that both porosity and pore size decreased with increasing heat treatment time (<i>t</i> = 0.5, 6, 12 h) and temperature (<i>T</i> = 200, 250, 300, and 350 °C). FTIR was used to explore the change of chemical bonds and found that dehydrogenation, cyclization, and cross-linking reactions occurred in thermal treatment. Compared with original PAN membrane, the hydrophobicity of heat-treated membranes was obviously improved. The heat-treated membrane PAN-250-6 (PAN–temperature–duration) was selected and immersed in various boiling solvents for 24 h to test material stability. PAN-250-6 membrane presented excellent thermal and chemical stability especially in strong solvent, <i>N</i>,<i>N</i>-dimethylacetamide (166.1 °C), whereas original PAN membrane was dissolved completely. For comparison, PAN and PAN-250-6 HFMs were further chosen for packing modules, which were used for the distillation of isopropanol–water solution. During 10 days of operation, module PAN-250-6 showed high separation efficiency with comparatively low height of mass transfer unit (HTU) and larger overall mass transfer coefficients in the ranges of 0.1–0.18 m and 2.5–3.2 cm/s respectively. By analyzing the impact of wetting condition on mass transfer, it was found that membrane resistance should be sensitive and attributed more to the change of the overall resistance. The membrane with better hydrophobicity after heat treatment was more conducive to distillation with HFMs. With superior thermal and chemical stability in distillation, this kind of heat-treated hollow fiber structured packing will be promising in future distillation applictions