Automated urinary steroid profiles by capillary column gas-liquid chromatography and a computing integrator

Area of Science:

• Biochemistry
• Analytical Chemistry
• Endocrinology

Background:

• Accurate quantification of urinary steroid metabolites is crucial for diagnosing endocrine disorders.
• Traditional methods like peak height measurements can introduce errors, particularly at higher concentrations.
• Automated techniques offer potential for improved precision and efficiency in steroid analysis.

Purpose of the Study:

• To evaluate the accuracy of automated gas-liquid chromatography with a computing integrator for quantifying urinary steroid metabolites.
• To compare the results obtained from computing integrators with traditional peak height measurements.
• To present mean excretion levels of key steroid metabolites in healthy males and females.

Main Methods:

• Automated gas-liquid chromatography (GLC) was employed for steroid metabolite determination.
• A 20-m glass capillary column was utilized for chromatographic separation.
• A computing integrator was used for quantitative analysis, with results compared to peak height measurements.

Main Results:

• Automated GLC with a computing integrator showed good agreement with peak height measurements for concentrations up to 2 mg/24 h.
• Discrepancies were observed at higher concentrations, with peak height measurements yielding falsely low values for C21 steroids.
• Mean urinary excretion values for seven steroid metabolites in healthy males and females were determined.

Conclusions:

• Automated gas-liquid chromatography with computing integration provides a reliable method for urinary steroid metabolite quantification.
• Computing integrators offer superior accuracy over peak height measurements, especially for C21 steroids at higher concentrations.
• The study establishes reference ranges for key steroid metabolites in healthy adults, aiding clinical interpretation.