Thin films, rich in primary amines (CNH2), were deposited from nitrogen (N2) or ammonia (NH3) and ethylene (C2H4) with different gas mixture ratios, R, using three different methods: atmospheric‐pressure‐ or low‐pressure plasma polymerisation (PP), and vacuum‐ultraviolet photo‐polymerisation. They are designated H‐plasma‐polymerised ethylene (PPE):N, L‐PPE:N and ultraviolet‐polyethylene (UV‐PE):N, respectively. Of interest in cell‐culture and tissue engineering, all three coating‐types were examined with regard to stability in air and solubility in water, compared with other deposits in the literature that were obtained from single precursors such as allylamine (AA) or n‐heptylamine (HA), PP‐AA and PP‐HA, respectively. The three types of deposits, prepared using comparable R values, were characterised by X‐ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, scanning electron microscopy and atomic force microscopy and found to vary significantly among themselves in regard to their [N]‐ and [NH2] concentrations, and their chemical stabilities during long‐term exposures to air or aqueous solvents. UV‐PE:N and L‐PPE:N films were found to compare very favourably with their best PP‐AA and PP‐HA counterparts; we conclude that the additional important fabrication parameter (the gas mixture ratio, R) is a major asset for preparing stable NH2‐rich organic coatings with optimal properties.

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The quantification of primary and secondary amines in plasma polymerized allylamine and plasma copolymers of allylamine/octadiene films was carried out using chemical derivatization followed by X‐ray photoelectron spectroscopy. Data was analyzed using a combination of the peak‐fit‐analysis method (PFA) and the quantitative‐elemental‐analysis method (QEA). The latter method overestimates the secondary amine contribution, since it does not account for the additional reaction of TFAA with OH groups that may be present as a result of surface aging effects. In the current work the PFA method has been extended to enable the separation of –OH groups and secondary amines, thus allowing for a more precise determination of the secondary amine groups even after surface aging.

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Human U‐937 monocytes are notoriously reluctant to adhere to normally cell‐adhering surfaces, for example tissue‐culture poly(styrene). In earlier work, these laboratories observed that organic thin films prepared by plasma‐ or ultraviolet‐assisted polymerisation, so‐called PVP:N, did facilitate the adhesion and proliferation of U‐937 under the condition that the concentration of primary amines exceed a critical value, [NH2]crit ≥ 4.2 at.%. That criterion being satisfied by pristine Parylene diX AM, we have compared its performance with those of particular types of PVP:N, L‐PPE:N and UV‐PE:N. Here, we report a study of aging of these coating types in atmospheric air, then of time‐dependent adhesion of U‐937 cells. Although there are similarities, the coatings also manifest interesting differences that so far elude detailed understanding.

Bioactive coatings constitute an interesting approach to enhance healing around implants, such as stent-grafts used in endovascular aneurysm repair. Three different plasma techniques, namely NH₃ plasma functionalization and atmospheric- or low-pressure plasma polymerization, are compared to create amino groups and covalently bind CS and EGF bioactive molecules on PET. The latter presents the greatest potential. CS + EGF coating is shown to strongly decrease cell apoptosis and cell depletion in serum-free medium, while increasing cell growth compared to unmodified PET. This versatile biomimetic coating holds promise in promoting vascular repair around stent-grafts, where resistance to apoptosis is a key issue.

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Photo‐induced polymerization of hydrocarbon “monomers”, both unsaturated C2H4 and saturated CH4, has been carried out by vacuum‐ultraviolet (VUV) irradiation of the flowing gases at reduced pressure, employing near‐monochromatic radiation from Kr and Xe lamps. Using mixtures with NH3, the source of bound N in the coatings, similar concentrations, [N], can be achieved in both UV‐PE(M):N and low‐pressure plasma polymers, L‐PPE:N, but the former are much richer in primary amines, with selectivity values ([NH2]/[N]) up to 75%. UV‐PE:N and UV‐PM:N films prepared with gas mixture ratios, R, between 0.75 and 1.0 possess the main characteristics required for bio‐technological applications: (i) NH2‐rich, (ii) low loss of [NH2] upon exposure to atmosphere or water, and (iii) very low solubility in aggressive solvents, e.g., water. The VUV photo‐polymerization process, governed by reactions of free radicals from the gas‐phase, appears to result in more stable, more densely cross‐linked deposits than those from plasma‐assisted processes.