Electrochemical immunosensor for serum parathyroid hormone using voltammetric techniques and a portable simulator

Area of Science:

• Electrochemistry
• Nanomaterials Science
• Biomedical Engineering

Background:

• Parathyroid hormone (PTH) is a critical biomarker for bone and mineral metabolism disorders.
• Accurate and rapid PTH detection is essential for clinical diagnosis and management.
• Existing PTH detection methods can be time-consuming and require specialized laboratory equipment.

Purpose of the Study:

• To develop a novel electrochemical immunosensor for sensitive and specific detection of parathyroid hormone (PTH).
• To utilize a nanocomposite of multi-walled carbon nanotubes (MWCNT) and gold nanoparticles (AuNP) for enhanced immunosensor performance.
• To evaluate the stability, reproducibility, and potential for point-of-care testing (POCT) of the developed PTH immunosensor.

Main Methods:

• Fabrication of a screen-printed carbon electrode (SPCE) modified with MWCNT-AuNP nanocomposite.
• Immobilization of anti-PTH antibodies and horseradish peroxidase (HRP) on the modified SPCE.
• Electrochemical characterization using cyclic voltammetry (CV), differential pulse voltammetry (DPV), and square wave voltammetry (SWV).
• Assessment of sensor performance including linear detection range, selectivity, stability, and reproducibility.

Main Results:

• The MWCNT-AuNP modified SPCE exhibited enhanced conductivity and electron transfer properties.
• The developed immunosensor demonstrated a linear detection range for PTH from 1-300 pg/ml.
• The sensor maintained 85% of its PTH sensing ability after 28 days of storage at 4°C.
• Low detection limits were achieved: 0.886 pg/ml (DPV) and 0.065 pg/ml (SWV).
• The electrochemical performance was unaffected by common protein interferences in human serum.

Conclusions:

• The developed electrochemical immunosensor based on MWCNT-AuNP/SPCE offers a sensitive, stable, and reproducible platform for PTH detection.
• The platform shows significant potential for rapid, label-free, and cost-effective point-of-care testing of PTH.
• This approach provides a promising alternative to conventional methods for PTH analysis in clinical settings.