E xamination of cerebrospinal fluid (CSF) total protein is used chiefly to detect increased permeabili ty of the blood-brain barrier to plasma proteins or increased intrathecal secretion of immunoglobulins (1). A rapid and quite precise method is required. The biuret method is considered as a potential reference method for total protein determination in biological fluids (2-4). It has been modi...

We evaluated the effect of dextran on values for total protein in serum as measured by the biuret method with five widely used automated instruments: the American Monitor Parallel; the Du Pont aca II; the Roche Cobas-Bio; the Kodak Ektachem 400; and the Beckman Astra 8. Dextran concentrations as great as 25 or 30 g/L had relatively little or no influence on total protein measurements by the lat...

We evaluated a rate colorimetric method (Beckman) for measuring total protein in cerebrospinal fluid. The automated instrument we used was Beckman's ASTRA TM. A 100-microL sample of spinal fluid is introduced into the biuret reagent in the reaction cell and the increase in absorbance at 545 nm is monitored for 20.5 s. Solid-state circuits determine the rate of alkaline biuret-protein chelate fo...

In many areas of food processing it is desirable to reduce the length of protein molecules. The two most commonly used methods employ either inorganic acids or proteolytic enzymes to cleave peptide bonds between adjacent amino acids. Proteolytic enzymes can reduce the viscosity of aqueous protein mixtures as well as the volume of insolubles. In the Alaskan seafood industry, liquification of pro...

Protein concentration in patients’ urine ranges from almost null to about 60 g/L. Many substances in urine can interfere with the reaction between protein and reagent. Moreover, many kinds of dye show a strong tendency to stick to glassware, including cuvettes. For these reasons, no really satisfactory colorimetric method has yet been devised for assay of protein in urine, especially in an auto...

A soluble specific substance was isolated from Mexican typhus Rickettsia which gave, with Proteus X-19 antiserum and typhus human serum, the same precipitation reactions as the polysaccharides extracted from B. proteus OX-19. The soluble specific substance extracted from Rickettsia and Proteus OX-19 is likely to be of a polysaccharide nature owing to the strong Molisch reactions obtained with s...

The basic concept of the fast analyzer has been previously described using simple experimental systems suitable for orienting studies and for proof-of-principle (l-6). Methods for simultaneously moving measured sample and reagent volumes into a series of cuvets in a cuvet rotor, for achieving rapid mixing, and for displaying and recording the data have been devised and applied to simple analyse...

AIMS To advise a system of neuronal networks which can classify the densitometric patterns of serum electrophoresis. METHODS Digitised data containing 83 normal and 132 pathological serum protein electrophoresis patterns were presented to four neuronal networks containing 1900 neurons. Network 1 evaluates the integrated values of the albumin, alpha 1, alpha 2, beta and gamma fractions togethe...