Polyethersulfone dead-end tube as a scaffold for artificial lacrimal glands in vitro.

Polyethersulfone (PES) dead-end tubes were fabricated by means of a phase inversion technique, and then were used as scaffolds for artificial lacrimal glands. The wall of the dead-end tubes could allow nutrients such as ascorbic acid, L-tryptophan, and glucose to pass through, but prevents rat IgG from passing through. Lacrimal acinar epithelial cells of Sprague-Dawley rats were cultured in vitro, and cell-associated secretory component was detected with an immunofluorescence technique to identify the acinar cells. The second passage of the cells showed high degree of cellular differentiation, and was used to seed on the PES tubes. The results showed that the PES tube could support the attachment, the growth, and the proliferation of the rat lacrimal acinar cells. Thus, PES is a substrate for the growth of lacrimal acinar cells and may be a useful scaffolding biomaterial for tissue engineering, such as a scaffold for artificial lacrimal glands.

Nanoporous membrane-based cell chip for the study of anti-cancer drug effect of retinoic acid with impedance spectroscopy.

This paper presents a novel microchip with nanoporous anodic alumina membrane for the study of anti-cancer drug effect of retinoic acid (RA) on human esophageal squamous epithelial KYSE30 cancer cells in vitro with impedance spectroscopy. The impedance experiments with 0.01 M retinoic acid (RA) were explored for the study of anti-cancer drug effects on KYSE30 cancer cells. The impedance was monitored in the time domain at 0.1 Hz. After addition of 0.01 M RA to the cell chip, the impedance magnitude decreased with time from the value with confluent cell layer and returned to the initial base line after around 12h. The fluorescence experiments testified that this impedance decrease was due to the cell morphology change induced by RA.

BSA-modified polyethersulfone membrane: preparation, characterization and biocompatibility.

A polyethersulfone (PES) membrane was modified by blending with a co-polymer of acrylic acid (AA) and N-vinyl pyrrolidone (VP), followed by immobilization of bovine serum albumin (BSA) onto the surface. The scanning electron microscopy results showed that PES had good miscibility with the co-polymer. X-ray photoelectron spectroscopy confirmed the existence of P(VP-AA) co-polymer on the surface of the blended membrane and the existence of BSA after the immobilization process. The amount of BSA immobilized on the surface of the membranes was determined. It was found that the protein adsorption amounts from BSA, human plasma fibrinogen and diluted human plasma solutions decreased significantly after modification. According to the circular dichroism results, the proteins kept more alpha-helix conformation in the modified membranes than in the pure PES membrane. The number of the adhered platelets was reduced, and the morphology change for the adherent platelets was also suppressed by the modification with BSA. The SEM morphological observation of the cells and the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay demonstrated that the BSA-modified PES membrane surface promoted endothelial cell adhesion and proliferation.