Development of colloidal gold-based immumochromatographic assay for the rapid detection of medroxyprogesterone acetate residues in biological materials

Abstract

A competitive colloidal gold-based immunoassay in lateral-flow format for the rapid detection of medroxyprogesterone acetate (MPA) in biological materials was developed. A nitro-cellulose membrane strip was separately coated with goat anti-rabbit IgG (control line) and MPA hapten-OVA conjugate (test line). Anti-MPA polyclonal antibody labelled with colloidal gold particles was first incubated with MPA. The limit of detection for lateral flow was 5 ng g⁻¹ for detecting an MPA standard solution, and the limit of detection was 10 ng mL⁻¹ for detecting the MPA spiked in pig urine and 10 ng g⁻¹ for spiked in pig liver. The results were confirmed by high-performance liquid chromatography tandem mass spectrometry (HPLC/MS/MS) and indicated that there was a good agreement between both methods (R ² = 0.976). The assay time for the test was less than 5 min, suitable for rapid testing on site.

Keywords:

• MPA
• Lateral-flow
• Colloidal gold-based immunoassay

Acknowledgements

We greatly appreciate the financial support from NSFC on research project No. 20475022 and SFC of Jiangsu province on research project No. BK2004023.