Evaluation of new product for hydroxyproline determination in HPLC

For the determination of hydroxyproline, HPLC methods are specific and sensitive, but expensive and time consuming. The aim of this paper was to evaluate a modification to the HPLC method, which employs a precolumn derivatization by DABSYL chloride. The modified method includes a further derivatization by orthophthalaldehyde (OPA), but it simplifies the chromatographic separation, saving time and reagents. Precision, recovery, linearity and accuracy for both methods have been evaluated. The linear regression analysis of the data has given the following correlation: Y = 1.04 X - 1.08 (r = 0.996). Moreover we checked that the preparation of the mobile phase for the modified method may not be strict. In fact, only two identifiable peaks are present: internal standard amino acid (1st peak) and hydroxyproline amino acid (2nd peak).