immobilization of acetylcholinesterase on solid surfaces chemistry and activity studies

a method for covalent attachment of the enzyme acetylcholinesterase (e.c. 3.1.1.7, electric eel) on two different solid surfaces (glass and platinum) is described. the chemistry includes covalent bond formation between a hydroxyl group on the surface, a thiol-terminal silane, a heterobifunctional crosslinker, and the enzyme. the activity ..

critical review of the stabilisation of polyacrylonitrile

the pre-oxidative stabilisation of polyacrylonitrile (pan) is a crucial step in the production of pan-based carbon fibres. much research has been devoted in the 1950s and 1960s towards elucidating the reactions undergone by pan during stabilisation. in the past, the mechanism of stabilisation was quite controversial, with much dispute abo..

controlling and predicting monoclonal antibody production in hollow-fiber bioreactors

a simple optimization strategy is described which enables monoclonal antibody (mca) production in hollow-fiber bioreactors to be controlled and predicted. the mca production rate is demonstrated to increase linearly with the uptake rates of glucose and glutamine and with the production rates of lactate and ammonia. the uptake and producti..

biosensors for process control

biosensors have been extensively studied during the last 20 years, and a myriad of laboratory biosensors have been developed improvements are required in biosensor design and performance before they become widely accepted in industrial process monitoring however, as the biotechnology industry expands, biosensors may become more acceptable..

failure mechanism of urethane-elastomer-coated-fabric collapsible fuel tanks

the u.s. army currently has a large number of fabric reinforced elastomer tanks ranging in size from 100 to 210,000 gallons used for storage of fuels and other liquids in the field. collapsible fuel tanks may be required to hold hydrocarbon fuels such as jps, diesel, and gasoline for long periods of time under adverse conditions. the elas..

transfer coating with polyurethanes

it is over twenty years since pu coated fabrics first appeared on the european market. these were predominantly based on raised woven fabrics that sought to imitate leather in both appearance and properties. this was also the period when poromerics, microporous polyurethanes, were prominent in the market. the basic principle of transfer c..

formation of amide bonds in chitosan carboxymethyl ether

it has been shown by ir spectroscopy that the impairment in solubility of chitosan carboxymethyl ether in the form of an internal salt after drying or heat treatment takes place as a result of of the formation of amide crosslinks. the number of crosslinks formed increases with increase in temperature and duration of heating, and also with..

glucose biosensors based on thick film technology

various techniques for the fabrication of thick film biosensors are described. with electrodes printed on conventional thick film substrates, glucose is measured via the formation of hydrogen peroxide using glucose oxidase. additional diffusion barriers extend the linear range of the sensor up to 15 mm. using a new, flexible, unfired subs..

enzymatic synthesis of n-butyl oleate in a hollow fiber membrane reactor

a new type of semi-batch membrane reactor has been developed for the synthesis of short chain alcohol fatty acid esters. the synthesis of n-butyl oleate was carried out in the reactor at a temperature of 30 $degree$ c. the reaction was catalyzed by mucor miehei lipase, which was immobilized on the membrane walls in the form of macroscopic..

use of a stationary bed reactor and serum-free medium for the production of recombinant proteins in insect cells

insect cells (spodoptera frugiperda) have been cultured in a stationary bed reactor packed with a fibrous polyester carrier. when the bioreactor was perfused with serum-supplemented medium, a cell density of 6 $multiplied by$ 10**6 cells ml** $minus$ **1 packed carrier was reached. scanning electron microscopy investigations have shown th..