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Polymer Deposition (polymer + deposition)

Distribution by Scientific Domains

Polymers and Materials Science	50%
Medical Sciences	50%

Selected Abstracts

Microscopic high-resolution digital volumetric imaging of human hair fibers

INTERNATIONAL JOURNAL OF COSMETIC SCIENCE, Issue 2 2005
J. V. Gruber
Methods for examining cationic polymer deposition on hair are well known and polymers such as Polyquaternium-10 have enjoyed a significant commercial impact on shampoos and body washes as unique conditioning materials. It was recently reported that hair can be examined using a new microscopic called Digital Volumetric Imaging or DVI (10). By employing fluorescent dyes, deposition of cationic oligosaccharides onto damaged blond hair fibers was discussed. Because hair auto-fluorescences, the microscope allows for examination of hair fibers directly including viewing of the cuticle, cortex and melanin within the cortex and careful imaging even distinguishes the medulla of the hair fiber. In this paper, examination of six virgin hair types including: (1) Afro-American, (2) Asian, (3) European brown, (4) red, (5) blond and (6) gray was conducted looking for differences that each hair type brings to the visualizing technique. Digital manipulation of the fluorescent data allows for examination of interior hair fiber structures as well as the development of animated movies of three dimensional hair fiber structures. [source]

Acetaldehyde plasma polymer-coated PET fibers for endothelial cell patterning: Chemical, topographical, and biological analysis

JOURNAL OF BIOMEDICAL MATERIALS RESEARCH, Issue 1 2010
Afra Hadjizadeh
Abstract The objective of this study was to produce fibrous biomaterials with cell adhesive and cell repulsive capabilities for biomedical applications. To this aim, the surface of 100-,m diameter polyethylene terephthalate fibers were functionalized with acetaldehyde plasma polymer deposition followed by carboxymethyl dextran grafting onto the aldehyde-coated surfaces via a polyethyleneimine interlayer. The performance of the surface modification steps were confirmed by surface chemical composition analysis using X-ray photoelectron spectroscopy, surface topography analysis by atomic force microscopy, and scanning electron microscopy. The acetaldehyde plasma polymer-coated and polyethyleneimine-grafted substrates promoted human umbilical vein endothelial cells attachment, spreading and actin filaments/focal adhesions formation. In contrast, carboxymethyl dextran-grafted substrates resisted cell adhesion. These observations demonstrate that the current surface-modified polymer fibers can be used in tissue engineering applications, such as cell patterning substrates or vascular prosthesis development. © 2010 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2010. [source]

Selective Deposition of Ultrathin Poly(p -xylene) Films on Dielectrics Versus Copper Surfaces

CHEMICAL VAPOR DEPOSITION, Issue 5 2004
J.J. Senkevich
Ultrathin films of poly(p -xylylene) are selectively deposited on oxide surfaces but not on air exposed copper. The polymers are deposited under conditions favorable for forming highly conformal ultrathin films appropriate for ,pore sealing' the surface of ultra-low , dielectrics. Variable angle spectroscopic ellipsometry is used to measure the polymer deposit on SiO2, and shows the lack of deposition on air-exposed copper. X-ray photoelectron spectroscopic analysis of the copper samples shows deposition of adventitious carbon on the metal surface, and confirms that no polymer deposition occurs. [source]

Unraveling the genetics of exfoliation glaucoma

ACTA OPHTHALMOLOGICA, Issue 2008
F JONASSON
Purpose To give an account of our recent discovery (2007) of the association of lysyl oxidase like 1 (LOXL1) sequence variants and exfoliation glaucoma (XFG) as well as later replications in other populations. Methods We did a genome-wide association study on open angle glaucoma cases and controls using the Illumina 300 chip. This chip includes probes for 317.000 single , nucleotide polymorphisms (SNPs), that tag, as highly correlated surrogates about 80% of the 2.1 million known common SNPs in the Caucasian genome. For diagnosis of exfoliation syndrome a peripheral band or central shield of exfoliative material on the anterior lens capsule was required. Results When we had done 195 open angle glaucoma cases high genome wide significance was achieved on chromosome 15q24.1 an association later found to be confined to XFG only. This SNP (rs2165241T) was located in the first intron of the LOXL1 gene. We then added 11 correlated SNPs that are not on the Illumina chip and found that two non-synonymous variants in the first exon of LOXL1 can jointly account for all the observed association (R141L, OR 2.5; G153D, OR 20.1). Combined the variants explained 99% of the population attributable risk for exfoliation glaucoma. Conclusion These findings have now largely been confirmed in numerous American, Asian, Australian and European studies, and in all instances do these polymorphisms in the LOXL1 gene confer risk to XFG. LOXL1 is cross linking enzyme responsible for elastin polymer deposition in ocular tissue. The LOXL1 discovery is the first big hit in the search for genetic background for exfoliation glaucoma. These findings may soon influence monitoring of glaucoma suspects in the clinic targeting persons with the high risk haplotypes. [source]