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Hydrophilic modification of porous polyethersulfone (PES) membranes was achieved by Ar-plasma treatment followed by graft copolymerization with acrylamide (AAm) in the vapor phase. Both surfaces of the modified membranes were found to be highly hydrophilic, the permanency of which depends on the grafting yield. The graft reaction was confirmed by X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared (FTIR) spectroscopy. The grafting rate was dependent on plasma exposure time. The surface and pore structures of PES membranes were viewed using scanning electron microscopy (SEM), revealing no surface damage and only a slight alteration in pore structure. As a result of the incorporation of polar functionalities, the glass transition temperature (Tg) of both the Ar-plasma treated and AAm grafted membranes increased. A moderate change in the tensile strength of the modified membranes was also observed. Most importantly, the AAm grafting made the membrane surface less susceptible to adsorption of BSA proteins. The grafted membranes also give greater flux recoveries after cleaning, indicating that the protein fouling layer was reversible because of the hydrophilic nature of the modified membranes.

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Photocatalyzed TiO 2 nanoparticles have been shown to eradicate cancer cells. However the required in situ introduction of UV light limits the use of such a therapy in patients. In the present study, the non-photocatalyic anti-cancer effect of surface functionalized TiO 2 was examined. Nanoparticles bearing -OH, -NH2, or -COOH surface groups, were tested for their effect on in vitro survival of several cancer and control cell lines. The cells tested included B16F10 melanoma, Lewis lung carcinoma (LLC), JHU prostate cancer cells, and 3T3 fibroblasts. Cell viability was observed to depend on particle concentrations, cell types, and surface chemistry. Specifically, -NH 2 and -OH groups exhibited significantly higher toxicity than -COOH. Microscopic and spectrophotometric studies revealed nanoparticle-mediated cell membrane disruption leading to cell death. The results suggest that functionalized TiO 2 , and presumably other nanoparticles, may be surface engineered for targeted cancer therapy.

Summary: SiOxCyHz films are deposited by radio frequency plasma enhanced chemical vapor deposition (PECVD) using a mixture of HMDSO and oxygen as source gases. The gas phase species produced in HMDSO and HMDSO/O2 plasmas are investigated by optical emission spectroscopy (OES) and mass spectrometry (MS). These data reveal that oxygen dilution causes strong dissociation of the HMDSO monomer. The film composition was investigated with X‐ray photoelectron spectroscopy (XPS) and Fourier‐transform infrared (FT‐IR) spectroscopy. Low O2 dilution (≤50%) results in the deposition of polymer‐like SiOxCyHz films while higher O2 dilution (≥80%) results in the deposition of inorganic SiO2‐like films. Surface energy measurements show that the SiO2 films have higher surface energy than the polymer‐like SiOxCyHz films. Deposition rates are measured with variable angle spectroscopic ellipsometry and are strongly dependent on the percentage of O2 dilution in the feed mixture.