title: Gas chromatographic determination of guanidino compounds in uremic patients using glyoxal as derivatizing reagent.
abstract: The guanidino compounds guanidine, methylguanidine, guanidinoacetic acid, guanidinopropionic acid, guanidinobutyric acid and guanidinosuccinic acid were eluted and separated after pre-column derivatization with glyoxal from an HP-5 column (30 m × 0.32 mm i.d.) with film thickness 0.25 µm at an initial column temperature of 100 °C for 2 min, with ramping of 20°C/min up to 250 °C and a nitrogen flow rate of 3 mL/min. Detection was by flame ionization detection. Linear calibrations were observed within 0.1-20.0 µmol/L, with limit of detection within 0.024-0.034 µmol/L for each compound. The separation was repeatable with relative standard deviation (RSD) (n = 6) within 1.2-1.8 and 1.1-1.6% in terms of retention time and peak height/peak area, respectively. The method was applied for the determination of the guanidino compounds from serum of uremic patients (n = 7) and healthy volunteers (n = 8), and amounts were observed within 1.33-11.71 and 0.07-0.39 µmol/L with RSD 1.1-3.5 and 1.1-3.0%, respectively. The results were further supported by the standard addition method.
authors.affiliation: Institute of Advanced Research Studies in Chemical Sciences, University of Sindh, Jamshoro, Pakistan.
authors.forename: S A
authors.initials: SA
authors.lastname: Majidano
authors.forename: M Y
authors.initials: MY
authors.lastname: Khuhawar
mesh_terms: D002138:Calibration; D002849:Chromatography, Gas / Q000379:methods*; D006037:Glyoxal / Q000737:chemistry*; D006146:Guanidines / Q000032:analysis / Q000097:blood* / Q000302:isolation & purification; D006801:Humans; D057230:Limit of Detection; D014511:Uremia / Q000097:blood*
chemical_list: D006146:Guanidines; D006037:Glyoxal