Highly stable SERS-based mirrored aptasensor for selective detection of alpha-fetoprotein

Area of Science:

• Analytical Chemistry
• Biomedical Engineering
• Spectroscopy

Background:

• Alpha-fetoprotein (AFP) is a crucial biomarker for diagnosing certain cancers, necessitating sensitive detection methods.
• Existing AFP detection techniques may lack the sensitivity or speed required for early diagnosis.
• Surface-enhanced Raman spectroscopy (SERS) offers high sensitivity and specificity for molecular detection.

Purpose of the Study:

• To develop a novel aptasensor for sensitive and quantitative detection of alpha-fetoprotein (AFP).
• To utilize a mirror aptamer and SERS for a label-free or signal-based detection mechanism.
• To evaluate the sensor's performance in a clinically relevant matrix like patient serum.

Main Methods:

• Development of a SERS-based aptasensor incorporating a mirror aptamer.
• Utilizing cyanine 3 (Cy3) and 2-mercaptobenzimidazole-5-carboxylic acid (MBIA) as signaling molecules.
• Investigating AFP-induced alterations in SERS signals via a release recognition mechanism.

Main Results:

• The aptasensor demonstrated reliable and sensitive AFP detection within the concentration range of 0.0038-100 ng/mL.
• Achieved a low limit of detection (LOD) of 3.8 pg/mL for AFP.
• The sensor showed potential for AFP quantification in human serum samples.

Conclusions:

• The developed SERS aptasensor provides a highly sensitive and quantitative method for AFP detection.
• This technology holds significant promise for early cancer diagnosis and biomedical research.
• The quantitative SERS approach offers a valuable tool for clinical diagnostics.