[An improved high performance liquid chromatography method for determination of 1-hydroxypyrene in urine]

A method for determination of 1-hydroxypyrene in urine by alkaline hydrolysis and high performance liquid chromatography was improved and validated. The conjugated 1-hydroxypyrene in urine samples was decomposed by sodium hydroxide. The urinary 1-hydroxypyrene were extracted by dichloromethane, separated on reverse phase C18 and detected by fluorescence detector. Internal standard method was applied for the quantification of 1-hydroxypyrene. The standard curve was linear over the range 10-500 micrograms/L with a correlation coefficient > 0.999. The limit of detection and of quantification were 0.01 ng(signal to noise = 3) and 1.0 microgram/L urine, respectively. The recovery from the entire procedure was found to be 94.0% at 5 micrograms/L and 99.5% at 20 micrograms/L. The intra-day RSD values were found to be 6.2%, and 5.8% at 5, and 20 micrograms/L respectively (all at n = 6). The inter-day RSD values were 7.5%, and 8.9% for 5, and 20 micrograms/L, respectively (all at n = 6). This method is sensitive, efficient and reliable, and was successfully used for the determination of 1-hydroxypyrene in urine of workers exposed to polycyclic aromatic hydrocarbon.