Low Surface Energy Fluorocarbon Coatings Via Plasma Polymerization Process: Process Optimization and Protein Repellent Study

In the present study, low surface energy perfluorodecyl acrylate (PFDA) coatings and their copolymer coatings with diethylene glycol dimethyl ether (DEGDME) (i.e. PFDA-co-DEGDME) have been deposited through plasma enhanced chemical vapor deposition (PECVD) onto thermanox coverslips in a low pressure tubular inductively coupled RF plasma reactor. The influence of plasma parameters on surface chemical properties of the coatings were investigated by using fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FESEM), x-ray photoelectron spectroscopy (XPS) and water contact angle (WCA). The protein repellent properties of the plasma polymer coatings have been investigated using quartz crystal microbalance (QCM).JRC.DG.I.5-Nanobioscience

Ar/HMDSO/O2 Fed Atmospheric Pressure DBDs: Thin Film Deposition and GC‐MS Investigation of By‐Products

The thin film deposition in DBDs fed with Ar/HMDSO/O2 mixtures was studied by comparing the FT-IR spectra of the deposits with the GC-MS analyses of the exhaust gas. Under the experimental conditions investigated, oxygen addition does not enhance the activation of the monomer while it highly influences the chemical composition and structure of the deposited coating as well as the quali-quantitative distribution of by-products in the exhaust. Without oxygen addition a coating with high monomer structure retention is obtained and the exhaust contains several by-products such as silanes, silanols, and linear and cyclic siloxanes. The dimethylsiloxane unit seems to be the most important building block of oligomers. Oxygen addition to the feed is responsible for an intense reduction of the organic character of the coating as well as for a steep decrease, below the quantification limit, of the concentration of all by-products except silanols. Some evidences induce to claim that the silanol groups contained in the deposits are formed through heterogeneous (plasma-surface) reactions

Radio-Frequency Plasma Polymerized Biodegradable Carrier for in vivo Release of Cis-Platinum

A low pressure plasma process based on plasma deposition has been used to develop a drug delivery strategy. In this study, a drug delivery system based on different layers of plasma co-polymerized Poly ε-caprolactone-Polyethylene glycol (PCL-PEG) co-polymers was deposited on biocompatible substrates. Cis-platinum (118 μgm/cm2) was used as an anti-cancer drug and incorporated for local delivery of the chemotherapeutic agent. The co-polymer layers and their interaction with cancer cells were analyzed by scanning electron microscopy. Our study showed that the plasma-PCL-PEG coated cellophane membranes, in which the drug, was included did not modify the flexibility and appearance of the membranes. This system was actively investigated as an alternative method of controlling localized delivery of drug in vivo. The loading of the anti-cancer drug was investigated by UV-VIS spectroscopy and its release from plasma deposited implants against BALB/c mice liver tissues were analyzed through histological examination and apoptosis by TUNEL assay. The histological examination of liver tissues revealed that when the plasma-modified membranes encapsulated the cis-platinum, the Glisson\u27s capsule and liver parenchyma were damaged. In all cases, inflammatory tissues and fibrosis cells were observed in contact zones between the implant and the liver parenchyma. In conclusion, low pressure plasma deposited uniform nano-layers of the co-polymers can be used for controlled release of the drug in vivo

Design of calcium phosphate scaffolds with controlled simvastatin release by plasma polymerisation

Calcium Phosphates (CaPs) have excellent bone regeneration capacity, and their combination with specific drugs is of interest because it allows adding new functionalities. In CaPs, drug release is mainly driven by diffusion, which is strongly affected by the porosity of the matrix and the drug-material interaction. Therefore, it is very difficult to tune their drug release properties beyond their intrinsic properties. Furthermore, when the CaPs are designed as scaffolds, the increased complexity of the macrostructure further complicates the issue.; This work investigates for the first time the use of biocompatible plasma-polymers to provide a tool to control drug release from drug-loaded CaP scaffolds with complex surfaces and intricate 3D structure. Two different CaPs were selected displaying great differences in microstructure: low-temperature CaPs (Calcium-deficient hydroxyapatite cements, CDHA) and sintered CaP ceramics (beta-Tricalcium Phosphate, beta-TCP). The deposition of PCL-co-PEG (1: 4) copolymers on CaPs was achieved by a low pressure plasma process, which allowed coating the inner regions of the scaffolds up to a certain depth. The coating covered the micro and nanopores of the CaPs surface and produced complex geometries presenting a nano and micro rough morphology which lead to low wettability despite the hydrophilicity of the copolymer. Plasma coating with PCL-co-PEG on scaffolds loaded with Simvastatin acid (potentially osteogenic and angiogenic) allowed delaying and modulating the drug release from the bone scaffolds depending on the thickness of the layer deposited, which, in turn depends on the initial specific surface area of the CaP. (C) 2016 Elsevier Ltd. All rights reserved.Peer ReviewedPostprint (author's final draft

STABILISATION DES PROPRIETES DE SURFACE DU POLYPROPYLENE PAR PLASMA DE MELANGES HELIUM ET AMMONIAC EN VUE DE LA METALLISATION PAR L'ALUMINIUM

PARIS-BIUSJ-Physique recherche (751052113) / SudocCentre Technique Livre Ens. Sup. (774682301) / SudocSudocFranceF

Etude comparative des traitements laser excimère et plasma à décharge barrière diélectrique pour l'amélioration de l'adhésion PBT / Cuivre

La thèse a pour étude les effets d une irradiation laser excimère à 248 nm dans l air sous le seuil d ablation d un film de Poly Butylène Téréphtalate (PBT). Différentes techniques d analyses de surface permettent de caractériser les modifications de surface provoquée par ce procédé et les conséquences sur les propriétés d adhérence d un dépôt d une fine couche métallique de cuivre par évaporation thermique. Ces effets sont comparés à ceux d un traitement plasma à décharge barrière diélectrique (DBD) dans l air à la pression atmosphérique. Cette étude montre que le greffage de fonctions polaires oxygénées et/ou azotés selon les procédés utilisés permettent de renforcer l adhésion chimique entre le cuivre et le PBT ce qui améliore considérablement les propriétés d adhérence.PARIS-BIUSJ-Thèses (751052125) / SudocPARIS-BIUSJ-Physique recherche (751052113) / SudocSudocFranceF

Etude de la formation et du rôle des nanoparticules dans l'élaboration de couches minces d'oxyde d'étain par PECVD

Les couches minces d oxyde d étain sont largement utilisées dans différents domaines d applications comme les électrodes transparentes, ou les détecteurs de gaz. Il a été montré que la nanostructure des films permettait d améliorer sensiblement les propriétés optiques et électriques des couches minces de semiconducteurs. L objectif de ce travail de thèse est de synthétiser des films minces de SnO2, en contrôlant leur nanostructure et leur composition. Lors de la croissance de couches minces dans notre système de dépôt chimique en phase vapeur assisté par plasma (PECVD), des poudres nanométriques, polymérisées en phase plasma, peuvent s incorporer dans le film. Dans un premier temps, nous avons établi l influence des paramètres du procédé sur l évolution de la VDC, et relié ses variations à la granulométrie du film observé par miMEB. Nous avons ensuite étudié les dépôts obtenus en mode PECVD pulsé. Nous avons ainsi pu discuter différentes hypothèses sur les mécanismes de formations des poudres dans un plasma Ar/O2/(CH3)4Sn. La présence de nanocristallites incorporées au film d oxyde d étain a pu être établie.PARIS-BIUSJ-Physique recherche (751052113) / SudocSudocFranceF

DEPOT DE COUCHES MINCES D'OXYDE D'ETAIN PUR OU DOPE PAR PROCEDE PLASMA CVD BASSE PRESSION (CARACTERISATION ENERGETIQUES ET REACTIONNELLE DE LA DECHARGE PAR TECHNIQUES SPECTROSCOPIQUES ET MODELISATION)

PARIS-BIUSJ-Physique recherche (751052113) / SudocCentre Technique Livre Ens. Sup. (774682301) / SudocSudocFranceF

Comparaison de procédés de dépôt de couches minces semiconductrices à partir de précurseurs organométalliques (cas des réacteurs à flux alternes en phase vapeur (ALCVD) et réacteur plasma diode hors équilibre (PACVD))

PARIS-BIUSJ-Thèses (751052125) / SudocPARIS-BIUSJ-Physique recherche (751052113) / SudocSudocFranceF