Figure 4: Representative HPLC chromatogram obtained from the analysis of halofuginone and imipramin as internal standard in human ureter extract.(A)blank human ureter extract; (B) standard solution of halofuginone (5 μg/ml)and imipramine (10 μg/ml) spiked in human ureter extract.(t=0 min ammonium acetate (pH 4.7;10 mM)-ACN-triethylamine (70:30:0.2,v/v/v) ; t=10 min ammonium acetate (pH 4.7; 10 mM)-ACN-triethylamine(10:90:0.2, v/v/v)).