Utilizing molecular resonance-localized surface plasmon resonance coupling for copper ion detection in plasma

Area of Science:

• Biomedical Engineering
• Analytical Chemistry
• Nanotechnology

Background:

• Copper is a key factor in diseases like cancer, Alzheimer's, and diabetes.
• Accurate, rapid copper detection in plasma is needed for point-of-care diagnostics.
• Existing localized surface plasmon resonance (LSPR) platforms lack selectivity and sensitivity.

Purpose of the Study:

• To develop a sensitive and selective on-chip copper sensor for rapid, point-of-care detection.
• To address the limitations of previous copper detection methods.

Main Methods:

• Utilized 'Click' chemistry for assay selectivity, minimizing interference from other metal ions.
• Leveraged the coupling of molecular resonance and gold nanoparticle LSPR for enhanced sensitivity.
• Developed an on-chip colorimetric sensor for copper detection.

Main Results:

• Achieved a selective and sensitive on-chip copper assay with results in 60 minutes.
• Demonstrated minimal interference from other plasma metal ions.
• Measured copper concentrations as low as 4 μM with a linear range of 4–20 μM, relevant to physiological conditions.

Conclusions:

• The developed sensor provides a robust, colorimetric method for detecting copper in human plasma.
• This assay is suitable for point-of-care applications, aiding in the diagnosis of copper-related diseases.
• The sensor overcomes previous selectivity and sensitivity issues in LSPR-based copper detection.