HPLC method for determining serum methotrexate concentration in children patients / 国际检验医学杂志

ABSTRACT

Objective To establish a HPLC method for determining the serum methotrexate(MTX)concentration in children patients for monitoring the blood drug concentration in clinic.Methods The chromatographic analytical column was the Shimaduz C-18 colum(250 mm×4.6 mm,5 μm),the mobile phase was 0.025 mol/L NaH2 PO4 (pH 5.41)-methanol(76∶24,V/V).The flow rate was 1 .0 mL/min.The detection wavelength was 313 nm.The column temperature was set at 35 ℃.The plasma samples were deposited down the protein with 10% HClO4 ,the supernatant liquid 130 μL added with 1 mol/L NaOH 10 μL was directly injected for determination.Results The mass concentration of MTX in the range of 0.00-4.84 μmol/L and 4.84-10.00 μmol/L showed the good linear relation with the peak area,r 1 =1 ,r2 =1 .The mean recovery rates were 61.67%and 71.83%.Intra-day and inter-day precision were <10% and 12%,respectively(n =3).Conclusion The used method is simple,accurate and reliable with high sensitivity,good reproducibility and wide linearity range,which is suitable for the monitoring blood MTX concentration.