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Updated: Jul 10, 2026

Dry Film Photoresist-based Electrochemical Microfluidic Biosensor Platform: Device Fabrication, On-chip Assay Preparation, and System Operation
Published on: September 19, 2017
Development of a novel electrochemical impedance spectroscopy-based biosensor for bone formation-resorption biomarker
Rabia Şemsi1, Günay Afandiyeva2, Erdal Ergünol3
1Department of Medical Biochemistry, Institute of Health Sciences, Gazi University, Ankara, Türkiye.
Background:
This study aimed to develop a sensitive, selective, and cost-effective electrochemical impedance biosensor for the individual monitoring of two key bone turnover biomarkers: Procollagen Type I N-Terminal Propeptide (PINP) and β-C-Terminal Telopeptide (β-CTX).
Materials And Methods:
Gold (Au) electrodes were modified with 3-mercaptopropionic acid (3-MPA) to form a self-assembled monolayer (SAM). Monoclonal antibodies specific to PINP and β-CTX were covalently immobilized via EDC/NHS chemistry. Each immobilization step was characterized by Electrochemical Impedance Spectroscopy (EIS) and Cyclic Voltammetry (CV). Biosensor performance was evaluated in artificial serum, saliva, and urine, and compared against ELISA and ECLIA reference methods.
Results:
Under optimized conditions, the β-CTX biosensor demonstrated a linear detection range of 10-60 pg mL-1 (LOD: 2.9 pg mL-1), and the PINP biosensor a range of 10-60 ng mL-1 (LOD: 3.4 ng mL-1). Recovery values ranged from 84% to 105.6%. Strong correlations were obtained with ELISA and ECLIA (r ≥ 0.9977; p < 0.0001). Storage stability was approximately 8-10 weeks.
Conclusions:
The developed biosensor system enables determination of PINP and β-CTX in serum and non-invasive body fluids (saliva and urine), offering a low-cost, rapid alternative to conventional methods for monitoring metabolic bone diseases.

