Development and validation of high performance liquid chromatographic method for determination of gentisic acid and related Renal Cell Carcinoma biomarkers in urine

Abstract

A reversed phase liquid chromatographic (RPLC) method was developed to simultaneously detect and quantify creatinine, quinolinic acid, gentisic acid and 4-hydroxybenzoic acid in urine. These four bio-markers are present in relatively high concentrations in urine. Using a 5% methanol in water mobile phase with 0.6% acetic acid and a Zorbax C column, baseline resolution for all four biomarkers in synthetic urine was achieved. Better resolution was obtained for the separation of these four compounds when water rich mobile phases were used. Detection of the four biomarkers in urine using the proposed RPLC method is limited by background from the urine matrix for the later eluting compounds and from the dead marker for earlier eluting compounds.

Evaluation of statistical techniques to normalize mass spectrometry-based urinary metabolomics data

“…VSN uses non-linear transformations to produce a constant variance in the data [20]. Finally, Creatinine Normalization, the biological technique, was calculated by taking the ratio of the concentration of each metabolite to the observed level of creatinine [1,3,21,22]. More comprehensive details on the aforementioned normalization techniques, along with descriptions of several others, can be found in Ejigu et al [6], Kohl et al [14], Li et al [8], Li et al [9], and Wu and Li [4].…”

Novel absorbance peak of gentisic acid following the oxidation reaction

“…The medicinal properties of GA have been investigated widely and it was recently shown to be an effective radical scavenger, antioxidant, inhibitor of growth factors, and anti-carcinogenic substance [5][6][7][8]. Regarding pharmacokinetic and metabolic studies, GA was mainly measured by chromatography because of the difficulties associated with detecting GA and differentiating it from analogous compounds, such as ASA and other ASA metabolites, using other methods [9][10][11]. However, current methods for the measurement of GA require expensive analytical instruments and a complex method.…”

Molecular signature of renal cell carcinoma by means of a multiplatform metabolomics analysis

“…To date, many studies have been performed in the field of RCC and its subtypes. Metabolomics approaches, both untargeted [ [14] , [15] , [16] , [17] , [18] , [19] , [20] ] and targeted [ [21] , [22] , [23] , [24] , [25] ], with LC–MS [ 17 , 18 , 26 , 27 ], GC–MS [ 20 , 28 , 29 ] and NMR [ 15 , 16 , 30 , 31 ] have been applied. In six studies, at least two techniques were combined to increase metabolome coverage [ 14 , 19 , 22 , 24 , [32] , [33] , [34] ].…”