Quantitative detection of doping substances by a localised surface plasmon sensor.

Area of Science:

• Analytical Chemistry
• Biosensing Technology
• Nanotechnology

Background:

• Steroidal residues, such as stanozolol (Sz), are used in sports and animal husbandry.
• Accurate detection of these residues is crucial for regulatory compliance and safety.
• Conventional methods for small molecule detection can be complex and costly.

Purpose of the Study:

• To present a quantitative biosensing principle for steroidal residue analysis.
• To develop a simple, specific, and label-less immunosensor for stanozolol detection.
• To demonstrate the potential of localized surface plasmons (LSPs) for sensitive small molecule detection.

Main Methods:

• Utilized localized surface plasmons (LSPs) sustained by 3D noble metal nanostructures.
• Developed a label-less immunosensor for quantitative determination of stanozolol.
• Employed a simplified optical configuration avoiding total internal reflection illumination.

Main Results:

• Achieved highly specific, label-less detection of stanozolol in the nanomolar (nM) range.
• Demonstrated a smaller active sensor area compared to conventional SPR systems.
• Reported assay times that are short and instrumentation that is relatively inexpensive.

Conclusions:

• The LSP-based immunosensor provides a promising, simple, and cost-effective approach for quantitative steroidal residue analysis.
• The developed sensor exhibits detection levels comparable to SPR, with potential for further sensitivity enhancement to picomolar (pM) levels.
• This technology offers easier integration and reduced complexity compared to traditional SPR systems.