Creatinine in serum or urine is determined by Jaffe's reaction where creatinine produces quantitatively an orange color with picric acid in alkaline medium. After allowing an incubation time of 15 min at room temperature for color development the color is measured at 520 nm. Without taking into consideration the acidic nature of standard, protein free filtrate (PFF) of serum and urine, 1% picri...

In man, the relative concentrations of a-amino nitrogen in tungstic acid filtrates of erythrocytes and plasma have been determined by Hamilton and Van Slyke, using the ninhydrin method (2). Dunn et al. (3) reported assays of free tryptophan in blood serum, plasma, and red blood cells by microbiological means with Lactobacillus arabinosus. More recently, Gutman and Alexander (4) determined the l...

Whiteside, Roberta E. (Boston University School of Medicine, Boston, Mass.), and Edgar E. Baker. Interaction of Vi antigen with proteins. J. Bacteriol. 92:1597-1603. 1966.-Purified Vi antigen (Vi) mixed in equal amounts with bovine serum albumin (BSA) or human gamma globulin (HGG) at pH values above 4.7 formed a complex which was not precipitated by trichloroacetic acid or tungstic acid. At pH ...

In this paper, we suggest a novel recycling process for hard metal sludge that does not use ammonium paratungstate. Ammonia, which in the conventional is essential removing sodium and crystallized tungstate, was used process. Instead of ammonia, acid to remove tungstate resulting formation tungstic (H2WO4). Tungsten powders were successfully synthesized by hydrogen reduction through H2O decompo...

All the synthetic detergents and bile salts I have tried denature proteins such as hemoglobin and egg albumin at the isoelectric point 1 and keep the denatured isoelectric protein in solution. Some detergents in sufficiently high concentration can prevent the precipitation of denatured protein by trichloracetic acid, tungstic acid, and acid ferric sulfate. In fact, the origin of the present inv...

The non-specific analytical methods for the guanidinium compounds in biological fluids have been unsatisfactory for many years. The methods presented in this paper have a greatly improved specificity and are not too complex for use in the clinical laboratory. A modified Sakaguchi color reaction for substituted guanidines is used in each procedure. Guanidinoacetic acid is measured by developing ...