Improved method for the analysis of estrogenic steroids in pregnancy urine by high-performance liquid chromatography

The use of microparticulate packing materials and large injection volumes gives significant improvements in the analysis of complex samples, such as urine extracts by high-performance liquid chromatography. Lower detection limits and improved accuracy can now be attained. In addition, the combined use of adsorption and reversed-phase chromatography leads to reduced uncertainty in peak identification and gives more reliable quantification.