Coating Strategies (coating + strategy)

Distribution by Scientific Domains


Selected Abstracts


Stable Inverted Polymer/Fullerene Solar Cells Using a Cationic Polythiophene Modified PEDOT:PSS Cathodic Interface

ADVANCED FUNCTIONAL MATERIALS, Issue 15 2010
David A. Rider
Abstract A cationic and water-soluble polythiophene [poly[3-(6-pyridiniumylhexyl)thiophene bromide] (P3PHT+Br,)] is synthesized and used in combination with anionic poly(3,4-ethylenedioxythiophene):poly(p -styrenesulfonate) (PEDOT:PSS), to produce hybrid coatings on indium tin oxide (ITO). Two coating strategies are established: i) electrostatic layer-by-layer assembly with colloidal suspensions of (PEDOT:PSS),, and ii) modification of an electrochemically prepared (PEDOT:PSS), film on ITO. The coatings are found to modify the work function of ITO such that it could act as a cathode in inverted 2,5-diyl-poly(3-hexylthiophene) (P3HT)/[6,6]-phenyl-C61 -butyric acid methyl ester (PCBM) polymer photovoltaic cells. The interfacial modifier created from the layer-by-layer assembly route is used to produce efficient inverted organic photovoltaic devices (power conversion efficiency ,2%) with significant long-term stability in excess of 500,h. [source]


Evaluation of implants coated with rhBMP-2 using two different coating strategies: a critical-size supraalveolar peri-implant defect study in dogs

JOURNAL OF CLINICAL PERIODONTOLOGY, Issue 6 2010
Jaebum Lee
Lee J, Decker JF, Polimeni G, Cortella CA, Rohrer MD, Wozney JM, Hall J, Susin C, Wikesjö UME. Evaluation of implants coated with rhBMP-2 using two different coating strategies: a critical-size supraalveolar peri-implant defect study in dogs. J Clin Periodontol 2010; 37: 582,590. doi: 10.1111/j.1600-051X.2010.01557.x. Abstract Background: Implants coated with recombinant human bone morphogenetic protein-2 (rhBMP-2) induce relevant bone formation but also resident bone remodelling. Objectives: To compare the effect of implants fully or partially coated with rhBMP-2 on new bone formation and resident bone remodelling. Materials and Methods: Twelve, male, adult, Hound Labrador mongrel dogs were used. Critical-size, supraalveolar, peri-implant defects received titanium porous oxide surface implants coated in their most coronal aspect with rhBMP-2 (coronal-load/six animals) or by immersion of the entire implant in an rhBMP-2 solution (soak-load/six animals) for a total of 30 ,g rhBMP-2/implant. All implants were air-dried. The animals were euthanized at 8 weeks for histometric evaluation. Results: Clinical healing was uneventful. Supraalveolar bone formation was not significantly affected by the rhBMP-2 application protocol. New bone height and area averaged (± SE) 3.4 ± 0.2 versus 3.5 ± 0.4 mm and 2.6 ± 0.4 versus 2.5 ± 0.7 mm2 for coronal-load and soak-load implants, respectively (p>0.05). The corresponding bone density and bone,implant contact (BIC) recordings averaged 38.0 ± 3.8%versus 34.4 ± 5.6% and 25.0 ± 3.8%versus 31.2 ± 3.3% (p>0.05). In contrast, resident bone remodelling was significantly influenced by the rhBMP-2 application protocol. Bone density outside the implants threads averaged 74.7 ± 3.8% and 50.8 ± 4.1% for coronal-load and soak-load implants, respectively (p<0.05); bone density within the thread area averaged 51.8 ± 1.2% and 37.8 ± 2.9%, and BIC 70.1 ± 6.7% and 43.3 ± 3.9% (p<0.05). Conclusion: Local application of rhBMP-2 appears to be a viable technology to support local bone formation and osseointegration. Coronal-load implants obviate resident bone remodelling without compromising new bone formation. [source]


Bioactive and mechanically strong Bioglass®-poly(D,L -lactic acid) composite coatings on surgical sutures

JOURNAL OF BIOMEDICAL MATERIALS RESEARCH, Issue 2 2006
Q. Z. Chen
Abstract New coating processes have been investigated for degradable (Vicryl®) and nondegradable (Mersilk®) sutures with the aim to develop Bioglass® coated polymer fibers for wound healing and tissue engineering scaffold applications. First, the aqueous phase of a Bioglass® particle slurry was replaced with a poly(D,L -lactic acid) (PDLLA) polymer dissolved in solvent dimethyle carbonate (DMC) to act as third phase. SEM observations indicated that this alteration significantly improved the homogeneity of the coatings. Second, a new coating strategy involving two steps was developed: the sutures were first coated with a Bioglass®,PDLLA composite film followed by a second PDLLA coating. This two-step process of coating has addressed the problem of poor adherence of Bioglass® particles on suture surfaces. The coated sutures were knotted to determine qualitatively the mechanical integrity of the coatings. The results indicated that adhesion strength of coatings obtained by the two-step method was remarkably enhanced. A comparative assessment of the bioactivity of one-step and two-step produced coatings was carried out in vitro using acellular simulated body fluid (SBF) for up to 28 days. Coatings produced by the two-step process were found to have similar bioactivity as the one-step produced coatings. The novel Bioglass®/PDLLA/Vicryl® and Bioglass®/PDLLA/Mersilk® composite sutures are promising bioactive materials for wound healing and tissue engineering applications. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2006 [source]