Surface Modification and Film Preparation

The surface of any material governs its interactions with the environment. Knowledge over and control of these interaction is especially important when a material is in contact with the biosystem, for example, when applied as transplant, in tissue engineering, in cell cultures, and in blood contact, as weU as in biosensors in medicinal diagnosis, fluids analysis, environmental moititoring, and many other areas. Whereas, on the one hand, the bulk properties of the material are essential for its successful application, for example, as a catheter or a heart valve, special attention has to be paid to render to the surface suitable biocompatible or bioactive properties, no matter of the chemical composition of the bulk material. This is usually achieved by any surface modification process by low molar mass or polymeric compounds. An essential feature of such a modification procedure is the need for a permanent and bioresistant surface finish [87]. 

---

TABLE 3.4 Summaiy of Surface Modification and Film Preparation Techniques... 

An amperometric biosensor for OPC pesticides based on a CNT-modified transducer and an OPH biocatalyst is described. A bilayer approach with the OPH layer on top of the CNT film was used for preparing the CNT/OPH biosensor. The CNT layer leads to a greatly improved anodic detection of the enzymatically generated p-nitrophenol product, including higher sensitivity and stability. The sensor performance was optimized with respect to the surface modification and operating conditions. Under the optimal conditions the biosensor was used to measure as low as... 

Preparation of the samples included the following steps, surface modification of the substrate, polymer film deposition, thermal annealing, and selective degradation of the PLA phase, as illustrated in Fig. 4.1. The PLA removal does not alter the copolymers morphology and is comparatively easy, whereas the substrate choice, the surface modification, and thermal annealing protocol decisively influence the copolymer self-assembly behavior as will be discussed in the context of polymer phase separation [2,3]. The vast possible parameter space of the latter two preparation steps, combined with the numerous copolymers, presented a real challenge. 

R. Jayasekara, I. Harding, I. Bowater, G.B.Y. Christie, and G.T. Lonergan. Preparation, surface modification and characterization of Solution cast starch PVA blended films. Polym. Test. 23, 17-27 (2003). 

Surface modification and preparation on substrate have been reported to improve coating adhesion. For instance, premodification of the polyimide surface with self-assembled alkylsilane monolayers induced anisotropic lateral growth of PPy films along the substrate surface and enhanced film adhesion [76]. In this work, PPy film was electrochemically deposited onto Pt microelectrodes on a polyimide substrate and the PPy-coated microelectrode was used in external stimulation of cultured cardiac myocytes. 

Huang, C.H. Tsao, C.C. Hsu, C.Y. (2011). Study on the Photocatalytic Activities of Ti02 Films Prepared by Reactive RF Sputtering. Ceram. Int, Vol. 37, pp. 2781-2788 Inagaki, N. (19%). Plasma Surface Modification and Plasma Polymerization, Technomic Publ., ISBN 1-56676-337-1, Lancaster... 

In this work, Ti02 films prepared by sol-gel method were surface-modified by treating the surface with low temperature plasmas. And, effects of the modifications on the photocatalytic activity of the films under UV-A and fluorescence light were investigated. 

Ti02 thin films for surface modification were prepared by sol-gel method and dip-coating... 

CNT conductive surface modification Both SWNTs and MWNTs can be deposited directly from a CNT dispersion as a random network or thin film on conventional electrodes. From the point of view of their construction such electrodes are very easy to prepare but they may suffer from mechanical instability, thus limiting their application. 

Avseenko et al. (2001) immobilized antigens onto aluminum-coated Mylar films by electrospray (ES) deposition. Various surface modifications of the metallized films were studied to determine their abilities to enhance sensitivity. The plastic surfaces were firsf cleaned by plasma discharge treatment, followed by coating with proteins (BSA and casein) or polymers such as poly (methyl methacrylate) or oxidized dextran, or they were exposed to dichlorodimethyl silane to create hydrophobic surfaces. Protein antigen was prepared in 10-fold excess sucrose and sprayed onto the surfaces to form arrays with spot diameters between 7 and 15 pm containing 1 to 4 pg protein. 

In addition to C onions, C atoms condense into various kinds of chemically bonded forms, and they are known to have excellent physical properties depending on the bonding nature. This means that research and applications not only in the materials science but also in other scientific fields are expected. At JAERI, the optimum growth conditions have been successfully obtained for the preparation of high-quality Cgo, diamondlike carbon, and nanocrystalline diamond by means of ion-beam-assisted deposition [80-82]. The susceptibility of Ni/Cgo thin films to thermal treatment, the formation of nanocrystalline diamond and nanotubes due to codeposition of Co and Ceo, and the surface modification of glassy... 

---