Recent Patents on Materials Science - Volume 2, Issue 1, 2009

The intercalating non-covalent binding fluorescent cyanine dyes for nucleic acid detection are reviewed and the patent literature for the last two decades (since their discovery) is included. The synthetic methods for the preparation of unsymmetrical cyanine dyes that are useful as nucleic acid probes are presented. Most of the specific applications of such fluorescent cyanine dyes are reviewed and these include flow cytometry, PCR reactions, sequencing, hybridization, gel electrophoresis, capillary gel electrophoresis, liquid chromatography, quantification of DNA and RNA in solution, disinfection of blood products, diagnosis of different infections and diseases, melting curve analysis, covalent labeling for oligonucleotides and the application of such labeled nucleotides in clinical assays, staining and assessing the viability of the cells, chromosome staining etc. The outlook for current and future developments in this area is also outlined.

Ferritic stainless steel containing more than 7 wt. % of Al represents an interesting material for the production of components working at high temperature. To meet industrial needs of increased operating temperatures, many studies have been carried out to design FeCrAl(RE) alloys that are suitable for applications where the components have to work in oxidative environments for extended periods of operation, often at very high temperatures (>1000 °C) under cyclic operating conditions. Although a very good protectiveness against oxidation can be achieved for Al concentrations higher than 7 wt.%, mechanical properties of FeCrAl alloys are known to be poor at high temperature. High temperature strength and creep resistance can be improved by reducing grain boundary areas and by precipitating stable particles in the bulk alloy: this practice prevents grain boundary slip and dislocation movement. This paper reviews the patented progresses in the field of the production of FeCrAl alloys for high temperature applications such as heating elements and substrate of catalytic converters.

Human interferons are key cytokines secreted by the immune system. They exhibit antiviral, antitumor and immunomodulator activities. Interferons are degraded rather quickly in the organisms, especially when they are recognized as external substances. In order to make interferon therapies more effective, numerous delivery systems have been developed and widely studied in scientific papers and reviews. However, the aim of the present review is to study the available patents dealing with sustained interferon delivery. Delivery systems involving micro- and nanoparticles could be found abundantly among the inventions. Non-particulate delivery systems are represented principally by gels and liposomes. However, stents, domes and other types of matrices as well as conjugated interferons have also been patented. The polymers most frequently used for controlling release of interferon are poly(lactic-co-glycolic acid), polylactic acid and polyethylene glycol. Indirect methods constitute a challenging way to sustain interferon delivery by transferring protein encoding nucleic acids. Pegylated interferons are the leading commercial products, but encapsulated and genetically fused interferons are also close to enter the market. It is expected that nanoparticles and especially magnetic nanoparticles will have an important role in the future improvements.

For the last two decades, intensive research has been focused on developing reinforced polymers with incorporation of nanometric fillers. Amongst the different types of nanofillers, those based on layered silicates (commonly known as clays), have been most widely investigated. Dispersing clay sheets on a nanoscopic scale (so-called exfoliation) indeed allows materials with enhanced thermal, mechanical, rheological, flame retardancy and barrier properties to be produced. However, the nanocomposite performances are strongly dependent upon the extent of clay exfoliation. In order to enhance the compatibility between the pristine clay, hydrophilic, and the polymer, hydrophobic, and to achieve a good delamination of the nanolayers, an organo-modification of the clay is most usually necessary. This mini-review will provide an outline of patenting activity in the field of manufacturing organoclays through ionic exchange. The variety of organic modifiers and the diverse processing techniques will be detailed, aiming to extract the most relevant organoclays for successful nanocomposite formation at industrial scale.

Conventional Cr-matrix coatings electrodeposited from hexavalent Cr baths have been widely used for decoration and anti-wear. Electrodeposition of Cr from hexavalent Cr needs to be replaced by another material system due to the intense toxicity and carcinogenicity of hexavalent Cr. Trivalent Cr plating is considered to be a promising ‘environmental acceptable’ replacement technology for hexavalent Cr plating. This paper gives a review of patents and publications in the field of trivalent Cr plating. We primarily introduce the discharge mechanism of trivalent Cr, development of trivalent Cr electrolytes, anodic materials for the trivalent Cr plating, elimination of hexavalent Cr produced on the anode as a result of trivalent Cr oxidation and the electrodeposition of functional thick Cr coatings and black Cr coatings from trivalent Cr baths.

The ferroelectric thin film was widely investigated in detail in recent years. The ferroelectric properties of the thin films are obviously dependent on the microstructure of the film, which were influenced by some processing parameters for preparing the films, including precursor solution chemistry, nature of substrate, film thickness, and condition of heat treatment etc. In this paper, these processing dependences of the films are reviewed. The present article discuss some important patents related to ferroelectric thin films.

The aim of this project is to study the effects of chemical treatment on the tribo-performance of coir reinforced polyester (CFRP) composite. Alkaline treatment and bleaching method were used to perform the surface modification on the coir fibre. In order to investigate the wear performance of treated and untreated CFRP composites, the experimental works were conducted using Pin On Disc (POD) machine at different applied loads (10N, 20N, 30N) and constant rotational speed (2.8m/s). Debonding gap between the untreated coir fibre and matrix resulted in higher weight loss due to lack of protection from the fibres. The results revealed that tribo-performance of the CFRP composite depend on the test parameter and condition. Treated coir fibre exhibited better interfacial adhesion and improved the wear characteristic of the composites. Worn surfaces were observed by Scanning Electron Microscopy (SEM) and optical microscopy. The development of friction layer at the rubbing surface enhanced the interaction between the counterface and specimen. The present article discusses some important patents related to Tribo performance of CFRP Composites.

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