Direct sensitive quantitative lC/MS analysis of C-peptide from human urine by two dimensional reverse phase/reverse phase high-performance liquid chromatography.
We describe for the first time the direct quantitative analysis of human C-peptide from urine by isotope dilution assay. Implementation of 2-D reverse phase-reverse phase chromatography (2-D RP-RP) with SIM detection resulted in high assay sensitivity (LOQ= 5 pg on column), accuracy, and method ruggedness. Our experiments demonstrate the strong resolving capability of our proposed 2-D RP-RP platform which significantly reduces strong matrix effects and their resulting quantitation error over a wide range of urine concentrations. In contrast, single column methods (both SIM and multiple reaction monitoring) were found acceptable only for strongly diluted urine samples.
Rogatsky
Eduard
E
General Clinical Research Center Analytical Core Laboratory and Division of Endocrinology/Department of Medicine, Albert Einstein College of Medicine, Bronx, NY 10461, USA. rogatsky@aecom.yu.edu
Tomuta
Vlad
V
Cruikshank
Greg
G
Vele
Louis
L
Jayatillake
Harsha
H
Stein
Daniel
D
D002096:C-Peptide / Q000737:chemistry / Q000652:urine; D002138:Calibration; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D003920:Diabetes Mellitus / Q000378:metabolism; D006801:Humans; D012015:Reference Standards; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*
D002096:C-Peptide