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The adsorption and covalent immobilization of human immunoglobulin (HIgG) and lysozyme (LYZ) on surface-modified poly(tert-butyl methacrylate) PtBMA films have been evaluated using x-ray photoelectron spectroscopy (XPS), ellipsometry and atomic force microscopy (AFM). Surface modification of PtBMA (UV irradiation) afforded surfaces suitable for both the physical and covalent attachment of proteins. The XPS and ellipsometry results showed good correlation in terms of variable-dense/thickness protein layer formation between physisorbed and covalently bound proteins. The amount of physisorbed HIgG ranged from 23.0 +/- 1.6 ng mm(2) on PtBMA, with corresponding film thicknesses 17.0 +/- 1.2 nm. Covalent immobilization mediated through 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC)/N-hydroxysulfosuccinimide (sulfo-NHS) coupling chemistry, afforded 5.6-8 ng mm(2) of HIgG with a corresponding thickness of 5.9 +/- 0.6 nm on PtBMA. The attachment of LYZ to modified PtBMA surface was similarly translated, where adsorption yielded up to 15 ng mm(2), while covalent immobilization afforded typically 7-8 ng mm(2). The thickness of the adsorbed LYZ protein layer was 11.0 +/- 3.2 nm (PtBMA), suggesting the greater portion of protein adsorbs on surface-modified PtBMA.

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The object of the paper is the further investigation of unique superhard (35−40 GPa) nanocrystalline (nc) coatings based on W 3 C phase, which is chemically vapor deposited at low temperature 400−700 °C and atmospheric pressure from the mixture of WF 6 + C 3 H 8 + H 2 with the following partial pressure ratios: WF 6 /H 2 ) 0.04−0.09 and C 3 H 8 /H 2 ) 0.15−0.5. Propane must be preliminarily subjected to catalytic cracking at 560−570 °C for 10−150 s in the presence of a stainless steel surface. The novel W 3 C phase (A15 with a o ) 0.5041 nm) is different from well-known WC and W 2 C by its associated lattice and Vickers microhardness (HV 0.5N ) of 35−40 GPa. Deposits have shown that they are a mixture of both the W 3 C phase and r-and β-carbynes, which are chainlike carbon structures (−CtC−) n /(dCdCd) n . Nanocrystalline structure of the nc-W 3 C/nc-carbyne composite with a nanocluster size of 2−100 nm, which is typical for the majority of novel superhard coatings, was discovered. It was shown that the nc-W 3 C/nc-carbyne composite coatings have significant potential for industrial applications.

The immobilization efficiency of the complexes of oligonucleotide/poly(L-lysine) onto Poly(Styrene/Maleic Acid), PSMA, and Poly(Styrene/Maleic Anhydride), PSMAA, has been investigated using X-ray photoelectron spectroscopy and atomic force microscopy (AFM) in conjugation with fluorescence-based measurements of DNA attachment. A mono-molecularly thin layer of either electrostatically or covalently (via amide bond) coupled poly(L-lysine) (PL) allows the "switching" of the chemistry from a COOH-based to NH 2-based one. The COOHbased chemistry has the advantage of a high yield of reaction but the disadvantage of a low surface concentration of DNA molecules (negative-negative electrostatic exclusion) whereas the NH 2-based chemistry provides a higher surface concentration (positive-negative electrostatic attraction) but has a lower yield of covalent binding reaction. The immobilization efficiency of covalently coupled 26-mer oligonucleotides/poly(L-lysine) to polymeric surfaces was estimated as 0.3-0.5 x10 12 molecules/mm 2 for both polymeric surfaces studied. The electrostatic adsorption of poly(L-lysine)/oligonucleotides onto PSMA and functionalized PSMAA surfaces yielded 0.5 x 10 11 and 0.1 x 10 10 molecules/mm 2 , respectively. Although this mode of attachment is not "covalent binding" per se, the evidence is provided that this attachment is strong enough to withstand PCR cycles. The properties of these oligonucleotide/poly(L-lysine) complexes make them promising candidates for DNA-DNA hybridisation assays and PCR.