Human serum creatinine determination

SlEKMANN L (1985) Determination of creatinine in human serum by isotope dilution mass spectrometry a definitive method in clinical chemistry. J Clin Chem Clin Biochem 23 137-144. Singer R, Danzer K (1984) Homogenitatsuntersuchungen von Festkorpem mit Hilfe linearer Regressionsmodelle. Z Chemie 24 339-341. 

R. Stosch, A. Henrion, D. Schiel and B. Guettler, Surface-enhanced Raman scattering based approach for quantitative determination of creatinine in human serum. Anal. Chem., 77, 2005, 7386-7392. 

There are numerous methods to determine the nephrotoxic potential of a chemical or to study the mechanism(s) by which a chemical induces nephrotoxicity. In humans, the concern is most often related to either drug-induced or occupationally associated nephrotoxicity. Evaluation of nephrotoxicity in humans is limited primarily to the measurement of urinary changes (e.g., volume, enzymes, protein, etc.), BUN or serum creatinine concentrations, creatinine clearance, or renal biopsy. The measurement of an increase in urinary N-acetyl-jS-D-glucosaminidase (NAG) or alanine aminopeptidase (AAP) levels,... 

Creatinine The microbial enzyme creatinine deimi-nase (EC 3.5.4.21) works well in the enzyme thermistor giving a linear range from 0.01 to at least 10 mmol 1 This could be a very powerful assay for clinical use since it requires only one enzyme and is independent of endogenous ammonia. Unfortunately, the determination of creatinine in human serum requires a higher order of magnitude increase in sensitivity than is available with the present instrumentation. 

Recoveries of the present HPLC method were tested by using a pooled human serum, blood, or urine, to which were added various amounts of histidine prior to the sample preparation. The mean recovery values were in the range of 101-104%. The values of histidine in human sera, blood, and urine, determined by the HPLC method, were 85.6 15.0 pM ( = 47, mean SD), 95.3 pM (n = 2, 96.8 and 93.8 pM), and 1.13 0.48 mmol/mg of creatinine (n = 10, mean S.D.), respectively, which were in good agreement with their reported values. The coefficients of the day-to-day variation obtained with a pooled human serum, blood, or urine were below 1.0%. 

Stosch et al compared isotope dilution techniques with a novel surface-enhanced Raman scattering (SERS) method to determine creatinine in human serum. The procedure involved the use of isotopically labelled C and N, and PLS (87 calibration spectra covering the full range of neat creatinine). 

The GU levels of five healthy human urines were determined by this method. GU concentration being estimated to be 0.038 - 0.132 jig/mg creatinine with an average of 0.092 as shown in the figure 3. The result on the distributions of urea and serum GU level of normal rats and streptozotocin induced hyperglycemia rats is shown in Figure 4. The concentrations of GU in urine of streptozotocin-induced rats were significantly higher than that of normal rats. 

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