A new commercial method for the enzymatic determination of creatinine in serum and urine evaluated: comparison with a kinetic Jaffé method and isotope dilution-mass spectrometry.

Abstract

We evaluated a new, simple, enzymatic kinetic method from Wako Chemicals GmbH in comparison with a kinetic Jaffé method by using isotope dilution-mass spectrometry (ID-MS) as a reference method. An ID-MS-calibrated serum standard was used. Both the enzymatic and the Jaffé method correlated well with ID-MS, except for sera with high concentrations of bilirubin. Ethyl acetoacetate, acetone, and glucose in serum interfered somewhat with the Jaffé method but not with the enzymatic method. We conclude that the present enzymatic method has merit as compared with a Jaffé method for routine work, but is more expensive.

Cystatin C in Healthy Women at Term Pregnancy and in their Infant Newborns: Relationship Between Maternal and Neonatal Serum Levels and Reference Values

“…We measured serum creatinine using an enzymatic method in order to minimize analytical interferences from noncreatinine chromogens, bilirubin in particular. 34 In our population, no significant correlation was found between this protein and maternal and neonatal variables, such as weight, body mass index, age of mothers and sex, diet, gestational age of newborns. Moreover, cystatin C may be considered an independent serum biochemical marker with respect to creatinine and urea, as it is not significantly correlated with these substances.…”

“…1 Containing one nonglycosylated polypeptyde chain with 120 amino acid residues, cystatin C belongs to a recently defined superfamily of proteins, called the cystatins superfamily, 2 because all its members are cysteine proteinase inhibitors. 34 The human cystatin C gene has been cloned, sequenced, and located to chromosome 20pll.2, 5>6 and seems to be of the so-called housekeeping type, which is constantly expressed in most human tissues. 7 -8 Cystatin C is therefore steadily produced by all nucleated human cells and among cystatins, it is that with the highest molar concentration in seminal plasma, in the milk, and in the cerebrospinal fluid, where it is actively secreted by the choroid plexus.…”

Reagent- and separation-free measurements of urine creatinine concentration using stamping surface enhanced Raman scattering (S-SERS)

“…Due to the importance of creatinine in clinical research, a variety of analytical methods have been developed for detecting creatinine in urine, including Jaffe reaction spectrophotometric method [4], enzymatic method [5], capillary zone electrophoresis [6], high performance liquid chromatography (HPLC) [7], high performance thin-layer chromatography (HPTLC) [8], liquid chromatography tandem mass spectrometry (LC-MS) [9], gas chromatography mass spectrometry (GC-MS) [10], isotope dilution extractive electrospray ionization tandem mass spectrometry (ESI-MS) [11], Raman spectroscopy [12] and surface-enhanced Raman scattering (SERS) [13]. Compared to traditional analytical methods, Raman and SERS methods offer several advantages.…”

Determination of Urinary Creatinine in Washington State Residents via Liquid Chromatography/Tandem Mass Spectrometry

“…There are several published analytical methods for measuring creatinine in urine such as the Jaffé reaction [ 5 – 7 ], High Performance Liquid Chromatography (HPLC) [ 8 – 10 ], enzymatic methods [ 11 , 12 ], and Liquid Chromatography Tandem Mass Spectrometry (LC/MS/MS) techniques [ 13 – 15 ]. Some of the advantages using the LC/MS/MS method developed at the PHL compared to other LC/MS/MS methods include improved linearity, within-day and between-day precision, and lower injection volumes (less system stress).…”