Determination of hydroxyproline in plasma and tissue using electrospray mass spectrometry.

A simple and highly specific method that was developed for the determination of hydroxyproline in biological samples is described. This method could potentially be used for monitoring pathological conditions related to collagen degradation, as well as for screening remedial pharmaceuticals for efficacy. Tissue or plasma samples were prepared by hydrolysis and their hydroxyproline content was determined using spiked calibration curves and LC/MS/MS. Specificity of the method was evaluated using an API Time-Of-Flight (TOF) LC/MS to expose potential interferences. The method proposed here appears to be selective, convenient, precise (<10% R.S.D.), accurate (<10% RE), and sensitive over a linear range of 0.010-10 microg/ml.