Development of a novel electrochemical impedance spectroscopy-based biosensor for bone formation-resorption biomarker determination in body fluids.
This biosensor offers a promising low-cost alternative for monitoring bone biomarkers, but requires validation in human studies before clinical use.
Where it sits
this study against the rest of the cyclic glycine-proline (cgp) corpusSummary and findings
The study developed an electrochemical impedance biosensor for monitoring bone turnover biomarkers PINP and β-CTX in body fluids. The biosensor demonstrated strong correlation with ELISA and ECLIA methods. It offers a low-cost and rapid alternative for bone disease monitoring.
Abstract
<h4>Background</h4>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).<h4>Materials and methods</h4>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.<h4>Results</h4>Under optimized conditions, the β-CTX biosensor demonstrated a linear detection range of 10-60 pg mL<sup>-1</sup> (LOD: 2.9 pg mL<sup>-1</sup>), and the PINP biosensor a range of 10-60 ng mL<sup>-1</sup> (LOD: 3.4 ng mL<sup>-1</sup>). 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.<h4>Conclusions</h4>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.
Background
This study addresses the need for a sensitive and cost-effective method to monitor bone turnover biomarkers, specifically PINP and β-CTX, which are important in diagnosing and managing metabolic bone diseases. Current methods like ELISA and ECLIA, while effective, can be costly and time-consuming. Developing a biosensor that can provide similar accuracy at a lower cost and with faster results could significantly benefit clinical practice.
Methods
The study utilized gold electrodes modified with 3-mercaptopropionic acid to create a self-assembled monolayer. Monoclonal antibodies specific to PINP and β-CTX were immobilized using EDC/NHS chemistry. The biosensor's performance was evaluated using Electrochemical Impedance Spectroscopy and Cyclic Voltammetry in artificial serum, saliva, and urine. Its results were compared to ELISA and ECLIA reference methods.
Results
The biosensor for β-CTX showed a linear detection range of 10-60 pg mL^-1 with a limit of detection of 2.9 pg mL^-1. The PINP biosensor had a detection range of 10-60 ng mL^-1 and a limit of detection of 3.4 ng mL^-1. Recovery values ranged from 84% to 105.6%. The biosensor showed strong correlations with ELISA and ECLIA, with correlation coefficients of r ≥ 0.9977 and p < 0.0001. Storage stability was noted to be approximately 8-10 weeks.
Interpretation
The biosensor developed in this study shows promise as a low-cost and rapid alternative to traditional methods for monitoring bone turnover biomarkers. However, while the correlation with established methods is strong, the study's reliance on artificial fluids rather than human samples limits its immediate clinical applicability. Further validation in human subjects is necessary to confirm its utility in real-world settings.
Key findings
- β-CTX detection range: 10-60 pg mL^-1, LOD: 2.9 pg mL^-1
- PINP detection range: 10-60 ng mL^-1, LOD: 3.4 ng mL^-1
- Recovery values: 84% to 105.6%
- Correlation with ELISA and ECLIA: r ≥ 0.9977, p < 0.0001
- Storage stability: 8-10 weeks
Limitations
- Conducted in artificial fluids, not human samples
- No human clinical validation
- Short storage stability of 8-10 weeks