In vivo study of a fluorocarbon polymer-coated intraocular lens in a rabbit model

As a result of inflammatory processes, plaque formation on dental titanium implants often leads to clinically pathogenic situations. This special biofilm formation on (bio)materials in contact with saliva is initiated by ionic and protein interactions. In this interfacial process, albumin becomes a main constituent of dental pellicle. Interfacial reactions change the surface characteristics. They determine the following steps of macromolecular adsorption and bacterial adhesion. This work focuses on the dynamic contact angle analysis (DCA), which is a tool for online measurements of dynamic changes of wettability without disturbing the interface during detection. Repeatability of the DCA method has been assessed according to the Bland and Altman method. The kinetics and equilibrium data of shifts in the wetting tension hysteresis indicate ionic influences at the titanium/bovine serum albumin (BSA) interface: the Ca-mediated increase of the BSA adsorption on titanium and the adsorption maximum at the isoelectric point (IEP) of BSA. Ti was surface modified by Teflon AF polymeric coatings. The result of the assessment gives reason to consider Teflon AF as a reference material for DCA repeatability studies. This surface modification caused drastic changes in the dynamic interfacial reactions. Shifts in the wetting tensions during DCA adsorption-desorption experiments clearly demonstrated the partially irreversible adsorption of BSA on Teflon AF. In contrast, reversible adsorption behavior was detected on pure Ti surfaces. These findings strengthen the hypothesis that the analysis of dynamic changes in wetting tension and wetting tension hysteresis is a sensitive analytical method for the detection of dynamic interfacial changes at biomaterial/biosystem interfaces during the initial steps of biofilm formation.

Section: Introductionmentioning

confidence: 99%

Adsorption/desorption phenomena on pure and Teflon® AF‐coated titania surfaces studied by dynamic contact angle analysis

Rupp

Axmann

Ziegler

et al. 2002

“…Teflon-coated PMMA IOLs were prepared as previously described (n = 36), at the Centre de Transfert de Technologie du Mans, Département Matéri-aux-IRAP. 22,23 Teflon AF was supplied by Dupont de Nemours. Thermanox (Nunc, Naperville, IL) is a plastic used as a support in cell culture; it favors cell adhesion, proliferation, and migration.…”

Section: Test Materialsmentioning

confidence: 99%

“…16−19 We recently proposed the complete coating of PMMA IOLs with the first amorphous and transparent form of Teflon, Teflon AF. 20,21 The surfaces of Teflon-coated IOLs are highly hydrophobic and have antiadhesive properties, as demonstrated in in vitro 22 and in in vivo 23 studies. The influences that a biomaterial might have on different cellular properties involved at the biomaterialhost interface, such as cell adhesion, proliferation, and migration, can be evaluated using the organ culture method developed by Wolff 24 and modified by SigotLuizard and Sigot.…”

Section: Introductionmentioning

confidence: 99%

Evaluation of Teflon-coated intraocular lenses in an organ culture method

Werner

Nagel

et al. 1999

Self Cite

An amorphous and transparent form of Teflon is proposed as a coating of polymethylmethacrylate (PMMA) intraocular lenses (IOLs), rendering them highly hydrophobic. We used an organ culture method to evaluate cell adhesion, proliferation, and migration on Teflon-coated IOLs. Corneal explants from 14-day-old chicken embryos were placed on a semisolid culture medium and covered with uncoated PMMA (n = 36) and Teflon-coated PMMA (n = 36) IOLs and two controls, Thermanox (n = 84) and latex (n = 36). After incubation (7 days at 37 degrees C), a digital imaging system was used to measure the areas of the cell migration layers on the materials. The cells were then removed with tripsin-ethylenediaminetetraacetic acid and the cells detached at times up to 75 min were counted (Coulter(R) Multisizer System). The values were used to construct a cell disconnecting curve for each material. The areas of cell migration layers on uncoated and Teflon-coated IOLs were significantly different (p <.05). Cell disconnecting curves demonstrated that cells adhered less strongly to Teflon-coated IOLs than to the other materials. This organ culture method demonstrated that the coating of PMMA IOLs with Teflon AF(R) is correlated with antiadhesive and antiproliferative properties.

“…Three to 6 cm 2 of the material surface per mL of the leaching medium are necessary to perform the test. 20 As the total surface of a circle is calculated with the formula ϫ r 2 , the total surface of a 0.6-cm-diameter IOL is: 2 (faces) ϫ 3.14 ϫ(0.3) 2 ϭ 0.56 cm 2 . A group of 18 sterile Teflon-coated IOLs were immersed in 3 mL of the leaching medium (0.56 ϫ 6 ϭ 3.36 cm 2 /mL) and incubated in a temperature of 37°C for 30 days, in sterile conditions.…”

Section: Teflon-coated Iol Leachables and Cell Culturementioning

confidence: 99%

“…[1][2][3] IOLs are widely used to replace the natural lens after cataract surgery, and PMMA is the standard material for their manufacture. Teflon AF is the first amorphous and transparent form of Teflon to become available.…”

Section: Introductionmentioning

confidence: 99%

Neutral red assay of the cytotoxicity of fluorocarbon-coated polymethylmethacrylate intraocular lenses in vitro

Werner

Legeais

Nagel

et al. 1999

Self Cite

Polymethylmethacrylate (PMMA) intraocular lenses (IOLs) were coated with Teflon AF, an amorphous, transparent Teflon, to render them highly hydrophobic. Teflon-coated PMMA IOLs were immersed in culture medium for 30 days at 37 degrees C. Four concentrations of the IOL leachables, 2 concentrations of a toxic control (phenol), and complete liquid culture medium (nontoxic control) were incubated for 24 h in a 96-well plate containing confluent L-929 fibroblasts. The cytotoxic effect of each solution on the fibroblasts was quantitatively assessed by measuring the uptake of neutral red by the viable cells. After the extraction of the neutral red using 1% acetic acid-50% ethanol, the optical densities were measured with a microplate reader at 550 nm. Scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) were used to analyze the surfaces of the IOLs. Only the optical densities in the wells containing fibroblasts that had been in contact with the phenol solutions were significantly lower than those in the wells incubated with the nontoxic control solution (p < 0.01). There were no signs of surface alteration by SEM, apart from some crystals on the IOLs. The crystals were composed of Na and Cl, as demonstrated by XPS. Aqueous extractables from the Teflon-coated IOLs produced no cytotoxic effects in the neutral red assay used.