We describe a method for the 7-min determination of theophylline in less than 100 muL of serum. The procedure requires no centrifugation or solvent evaporation after extraction. Butylation is done on the gas-chromatographic column by injecting the serum extract followed by a butylating mixture which contains 1-iodobutane as the alkylating agent. The method is precise, accurate, and free of inte...

Gd2O3 nanoparticles were prepared by a two–step process; cathodic electrodeposition followed by heat-treatment method. First, Gd(OH)3 nanoparticles was galvanostatically deposited from nitrate bath on the steel substrate by pulse current (PC) mode. The deposition experiments was conducted at a typical on-time and off-time (ton=1ms and toff=1ms) for 60 min. The electrodeposited precursor was the...

Background: There are varieties of purification techniques for separation of human plasma proteins such as salting out, ion exchange chromatography, and ethanol fractionation. There are limitations for each method, for example in salting out method, the salt has to be removed in an additional step. Ion exchange chromatography is difficult for scaling up, and plasma fractionation is a time consu...

The laboratory diagnosis of acute or congenital rubella frequently rests on the presence of rubella specific IgM in serum.1'2 Separation of serum IgM from IgG by sucrose density gradient centrifugation followed by the demonstration ofhaemagglutinationinhibiting activity in the IgM containing fractions is widely used for this.' With swing-out rotors centrifugation times of 16 hours or more are n...

1. Brush borders were isolated from rabbit kidney-cortex homogenates by rate-zonal centrifugation through a sucrose density gradient in a B-XIV zonal rotor, followed by differential centrifugation. 2. The method of preparation gave brush borders of high purity with a reasonable yield. The morphological appearance supported the evidence from enzymic and chemical investigations, that the brush bo...

Synaptosomes are subcellular components isolated from nerve terminations that can be prepared by homogenizing brain tissue in isotonic sucrose solution followed appropriate centrifugation. Their preparation technique has a long history since synaptosomes were first endings and described Gray Whittaker 1962. The of produces presynaptic boutons alone or combination with fragments postsynaptic mem...

an air–assisted liquid–liquid microextraction method for the extraction and preconcentration of trace amounts of some synthetic phenolic antioxidants in biological fluids followed by their determination by gas chromatography–flame ionization detection has been reported. in this method the target analytes are extracted into a few microliters of carbon tetrachloride (extraction solvent) from an a...

The characteristics and intracellular localization of Ehrlich ascitestumor cellglutaminasewere investigated.It wasfound that these cells possess only the phosphate-dependent glutami nase isoenzyme, which requires 50 mM inorganic phosphate for maximum activation. The K.,@value of the enzyme for glutamine was 4.5 mM , and the optimum pH was between 8.0 and 8.5. Differential centrifugation of the ...