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[Determination of four kinds of environmental endocrine disruptors in blood serum of precocious puberty patients by high performance liquid chromatography].

OBJECTIVE
This study was directed to the development of a simple and highly sensitive method for determination of four kinds of environmental endocrine discrupters (EEDs) in the serum of precocious puberty patients using reversed-phase HPLC.


METHODS
The serum samples were extracted by n-hexane. The operating conditions were such as C18 column (4.6 mm x 250 mm 5 microm), methanol: H2O: trifuorocuetic acid (1000 : 50 : 1) as mobile phase at a flow rate of 1 ml/min. Using ultraviolet detector, DEHP and MEHP was determined with wavelength at 228 nm, p, p'-DDE was determined with wavelength at 238 nm. Fluorescence detector with the excitation and emission wavelength at 275 nm and 312 nm respectively were used to determine 4-NP.


RESULTS
There was a good linear relationship between the concentrations of the analytes in serum and their peak areas in the range of for DEHP, for MEHP, for p, p'-DDE and for 4-NP. The detection limit of the method was 1 ng/ml for each of the analytes. Recoveries of serum samples were 96.84% - 103.44% for DEHP, 87.69% - 104.92% for MEHP, 87.6% - 109.89% for p, p'-DDE, 98.57% - 105.1% for 4-NP.


CONCLUSION
The method is suitable for the determination of the four kinds of EEDs in serum. It is easy to dispose the samples. The volume of samples is decreased and the effect of detection is increased. The method is quicker and easier and could be widely used to determine these compounds. It is helpful for the clinical study of precocious puberty.