Poly(vinylidene fluoride) (PVDF) and polysulfone (PSf) are two polymers with excellent mechanical properties but insufficient biocompatibility mainly due to their surface hydrophobicity. This study has applied oxygen plasma treatments and dopamine coating on the two polymers and investigated the changes of the surface properties and interactions with mammalian cells. All modification steps were verified by means of Electron Spectroscopy for Chemical Analysis and contact angle measurements. Surface topology of materials and biomolecules was studied by atomic force measurements (AFM) and scanning electron microscopy (SEM). Protein adsorption was quantified by fluorescent imaging and Bradford method. The results showed that O(2) plasma altered the surface hydrophilicity effectively on PSf and more than two folds of oxidation were obtained, when compared with the pristine one. The change of surface wettability was less significant on the O(2) plasma treated PVDF due to less oxidation extent, which was identified by analyzing the chemical compositions. The provided functionalized PVDF and PSf surfaces were tested with bovine serum albumin and L-929 mouse fibroblasts to evaluate the effects of surface modifications on protein adsorption and cell attachments. The biocompatibility was effectively promoted to fourfold and twofold on the hydrophobic PVDF and PSf by applying O(2) plasma treatments within short treatment time. Moreover, the simple immobilization of polymers in dopamine solution resulted in hydrophilic surface coating with stability that caused threefold and twofold increases of biocompatibility on PVDF and PSf correspondingly.

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A chemical gradient possessing gradual change of amine concentration for every 100 carbon atoms (NHx/100 C) from 4.03 to 1.98 was prepared by plasma polymerization of allylamine on polypropylene films. Electron spectroscopy for chemical analysis and water contact angle (WCA) measurements revealed that the nitrogen incorporation resulted in the amine functionality (CN binding) and, therefore, the formation of the wettability gradient. The gradient showed the WCAs varied from 15° to 90° as the change of amine concentration on the gradient from the nitrogen rich end to the nitrogen deprived end. Furthermore, the interactions between the gradient with mammalian cells revealed that more than twofold cell density was found at the nitrogen rich end when compared with the nitrogen deprived end. Plasma polymerization was demonstrated as an effective method to create controllable chemical gradient and the obtained allylamine gradient was useful for biomaterial applications. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2013, 51, 1361–1367

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Tujuan - Penelitian ini bertujuan untuk memberikan penjelasan secara empiris tentang pengaruh literasi keuangan terhadap keputusan keuangan dan perilaku keuangan sebagai variabel intervening. Desain/Metodelogi/Pendekatan - Metode penelitian menggunakan deskriptif-kuantitatif. Sumber data diperoleh dari penyebaran kusioner terhadap 96 mahasiswa di Fakultas Ekonomi dan Bisnis Universitas Palangka Raya. Sampel diambil dari keseluruhan mahasiswa Fakultas Ekonomi dan Bisnis Universitas Palangka Raya yang berjumlah 2.598 yang diambil secara purposive sampling. Data yang terkumpul dianalisis dengan menggunakan pendekatan Structural Equation Modelling (SEM). Software yang digunakan adalah SmartPLS 3.0. Temuan Penelitian - Hasil penelitian menunjukkan bahwa literasi keuangan berpengaruh positif signifikan terhadap keputusan keuangan, literasi keuangan berpengaruh positif signifikan terhadap perilaku keuangan, perilaku keuangan berpengaruh positif signifikan terhadap keputusan keuangan, perilaku keuangan mampu memediasi pengaruh antara literasi keuangan terhadap keputusan keuangan. Orsinalitas/nilai – Mengembangkan konsep teori dari perilaku keuangan sebagai mediasi antar pengaruh literasi keuangan dengan keputusan keuangan