Creatine, creatinine

Diacetyl 10 g l-1 a-naphthol in 80 g 1 1 NaOH plus an equal volume of diacetyl (1 ml per litre water). Mix before use. Heat at I00°C for 2-3 min Arg Purple/red Mono- and di-substituted guanidines, e.g. creatine, creatinine, also react... 

EPMEs based on carbon paste modified with antibiotics vancomycin, teicoplanin and teicoplanin modified with acetonitrile are proposed for the determination of d-2-HGA [47]. The proposed electrodes can be used reliably for enantiopurity tests of d-2-HGA using direct potentiometric method of analysis. The linear concentration ranges recorded for EPMEs are 10 7-10 3, 10 7-10 2 and 10 6-10 2 mol/L with detection limits of 1.00 x 10 8, 1.00 x 10 8 and 1.00 x 10 7 mol/L for the vancomycin, teicoplanin and teicoplanin modified with acetonitrile-based EPME, respectively. The selectivity was determined over l-2-HGA, creatine, creatinine and some inorganic cations. The proposed EPMEs were applied for the assay of d-2-HGA in urine samples. The duration of one analysis is 10 min, including the calibration of the instrument and the determination of the amount of d-2-HGA in the urine sample. 

Creatine, creatinine, uric acid PDMS PAD End-channel (on-chip) Gold [143]... 

Jacobi, O., The composition of normal human stratum corneum and callus. 3. Lactic acid, creatine, creatinine, urea and choline, Arch. Dermatol. Res., 240, 107-118, 1970. 

Figure 20.24 Biosynthesis of creatine, creatinine phosphate, and creatine from arginine.

Glycine Purines Creatine Creatinine Porphyrins Glutathione Hippuric acid... 

M3. McGeer, E. G., McGeer, P. L., Miller, J. R., Deny, D., and Nichol, C., Excretion of 5-aminoimidazole-4-carboxamide and creatine creatinine ratios in human and mouse muscular dystrophy. Can. J. Biochem. Physiol. 40, 13 (1962). 

RP-HPLC procedures for the determination of creatinine and purine metabolites, such as allantoin, uric acid, xanthine, and hypoxanthine in ruminant urine, were described. Chromatography was achieved with a Cig column under isocratic conditions, and detection at 218 nm without allantoin derivatization. The chromatographic conditions were a compromise between the sensitivity and specificity of the measurement of each analyte, analysis time, and resolution of all analyte peaks from interfering compounds.Uremic toxins creatine, creatinine, uric acid, and xanthine were simultaneously determined in human biofluids, simply after dilution, with UV detection at 200 nm. This method was compared, for creatinine and uric acid, with conventional routine methods and did not give significantly different results. 

Simultaneous Determination of Creatine, Creatinine, Uric Acid, and Xanthine... 

Table 2 Chromatographic and sample preparation conditions for the simultaneous determination of creatine, creatinine uric acid and xanthine...

Samanidou, V.F. Metaxa, A.S. Papadoyannis, I.N. Direct simultaneous determination of uremic toxins Creatine, creatinine, uric acid, and xanthine in human biofluids by HPLC. J. Liq. Chromatogr. Relat. Technol. 2002, 25 (1), 43-57. 

Depression of the primary antibody plaque-forming cell response in rats suggests that methoxyethanol could inhibit the humoral immune system. Testicular atrophy and depression of sperm counts are noted in animal studies. Methoxyethanol, along with several other known testicular toxins, causes an increase in the urinary creatine/creatinine ratio as one of the earliest and most sensitive markers of testicular damage after acute exposure. Methoxyethanol is considered to be a mild skin and eye irritant. Methoxyethanol is not a contact sensitizer. 

An assay for uric acid in urine employing a PDMS and/or glass microchip for capillary electrophoresis has also been developed. This device can achieve separation and quantitation of uric acid in less than 30 seconds and a linear response over a range of 0 to lOOpM/L. To facilitate this measurement, dilutions of urine of the order of fiftyfold to seventy-fivefold were required. Other similar devices for the renal markers creatine, creatinine, p-aminohippuric acid, and uric acid in urine,and a microchip-based method for zone electrophoretic analysis of oxalate m urine have been reported. 

Van Pilsum JF, Martin RP, Kito E. Determination of creatine, creatinine, arginine, guanidinoacetic acid, guanidine and methyl-guanidine in biological fluids. 

Lac toctate Ala alanine Acac acetoacetonate Sue succinate Ci citrate creatine creatinine Gly glycine Ur urea... 

Manabe et al. (2448) identified the A-heterocyclic amine l-methyl-6-phenyl-l//-imidazo[4,5-fc]pyridm-2-amine (PhIP) in CSC. By their addition to tobacco, Clapp (751) reported the contribution of varions individnal amino acids (asparagine, aspartic acid, arginine, glutamine, glutamic acid, histidine, proline, lysine, tryptophan, phenylalanine, creatine, creatinine) to the Ames test mutagenicity of cigarette MSS. 

The most popular method involves 2-thiobarbituric acid (TBA) two molecules of 2-thiobarbituric acid are condensed with malonaldehyde. The emergent chromogen — the two tautomeric structures of the red TBA-malonaldehyde adduct — is determined at 532 nm, and also often at 450 nm, to determine aUcenals and aUcanals, respectively. The qualitative Kreis test was based on a similar principle it involved detection of the epihydrine aldehyde — a tautomeric malondialdehyde — in a color reaction with resorcine or phloroglucinol. The popularity of the TBA test stems from a correlation between the results and sensory evaluations. Paradoxically, this is related to the most important drawback of the TBA technique — its lack of specificity. In addition to the reaction with malonaldehyde, TBA forms compounds of identical color with other aldehydes and ketones, products of aldehyde interaction with nitrogen compounds, and also with saccharides, ascorbic acid, creatine, creatinine, trimethylamine oxide, trimethylamine, proteins, and amino acids. For this reason, the TBA test may even be treated as a proteolysis indicator (Kolakowska and Deutry, 1983). Recently, TBA-reactive substances (TEARS) were introduced, primarily to stress that the reaction involves hydroperoxides in addition to aldehydes. Due to the nonspecificity of the TEARS test, its results reflect the rancidity of food better than other conventional methods, especially off-flavor, which is caused by volatiles from lipids as well as being affected by products of lipids interaction with nitrogenous compounds. 

Methods for the separation of a series of guanidino compounds, such as creatine, creatinine arginine, cirgin-inosuccinic acid, agmatine etc. [384,385] and guanidine-containing peptides (angiotensin [386], leupeptin [387]) and their sensitive determination in body fluids have been reported. 

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