Proteins inorganic polymers

Differential scanning calorimetry (DSC) is a calorimetric method that finds widespread use in many fields, including protein dynamics, polymers, pharmaceuticals, and inorganic materials. DSC measures energy (heat) flow into a sample and a reference substance as a function of controlled increase or decrease of temperature. In a typical power-compensated DSC (Fig. 3.2), the sample and reference are placed on metal pans in identical furnaces each containing a platinum resistance thermometer (thermocouple) and heater. During a thermal transition (e.g., when a physical change in the sample occurs),... 

Many publications are devoted to adsorption of surfactants, proteins and polymers on latexes, but adsorption of inorganic ions on latexes does not seem to be very active field. Latexes are also used as model colloids in studies of heterocoagulation, i.e, adsorption of colloids on colloids. 

Polymers may also be obtained from another source—nature. Cellulose, the principal constituent of cotton and a major constituent of wood, is a polymer. So also are lignin, natural rubber, gutta percha and proteins. Sand (silica) may be considered as an inorganic polymer. Whilst many of these are of value unmodified, some, like cellulose, cannot be consider as plastics in their natural state, but if chemically modified by man useful plastics materials such as cellulose acetate, celluloid and ethyl cellulose may be obtained. 

Berzelius, Jons Jakob (1779-1848) A physician and chemist born in Sweden, Berzelius was secretary of the Royal Swedish Academy of Sciences for thirty years. He is credited with discovering the law of constant proportions for inorganic substances and was the first to distinguish organic from inorganic compounds. He developed a system of chemical symbols and a table of relative atomic weights that are stiU in use. In addition to coining such chemical terms as protein, catalysis, polymer, and isomer, he identified the elements cerium, selenium, silicon, and thorium. 

Some commercially available protein-inert polymers commonly used in microfluidic applications, all of which require permanent surface modification, are polyacrylamide, poly(N-hydroxyethylacrylamide), poly(NJl -di-methylacrylamide) (PDMA), polyvinylpyrrolidone (PVP), poly(vinyl alcohol) (PVA), hydroxyethylceUulose (HEC), and hydroxypropylmethylcellulose (HPMC). To permanently attach protein-resistant materials to the channel surface, high-energy sources, special chemistries, or even strong physical adsorption have been employed to introduce reactive functionalities. After activation, protein-resistant polymers can be anchored via UV-initiated free-radical polymerization. Polymeric materials usually do not have good solvent and heat resistance compared with inorganic materials, and hence it is necessary to take precautions during surface treatment to avoid serious damage to the microstructure or alteration of the physical properties of the bulk material. 

Pitukmanorom, R, Yong, T. H., and Ying, J. Y. 2008. Tunable release of proteins with polymer-inorganic nanocomposite microspheres. Adv Mater 20 3504-9. 

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