Surface plasmon resonance biosensor for dopamine using D3 dopamine receptor as a biorecognition molecule

Area of Science:

• Biomedical technology
• Biosensor development
• Analytical chemistry

Background:

• Dopamine (DA) plays a crucial role in human metabolism, necessitating high-performance sensing methods.
• Existing methods for DA detection face challenges in sensitivity and specificity.
• Biomedical technology requires advanced tools for accurate DA monitoring.

Purpose of the Study:

• To develop a novel bioaffinity sensor for dopamine (DA) detection.
• To utilize a D(3) dopamine receptor (DA-RC) as the recognition element for enhanced specificity.
• To establish a sensitive and stable platform for DA quantification.

Main Methods:

• Surface plasmon resonance (SPR) imaging was employed for real-time detection.
• A conjugate of DA with bovine serum albumin (BSA) was synthesized and immobilized on an SPR gold surface.
• Atomic force microscopy (AFM) was used to characterize the sensor surface homogeneity.
• Indirect competitive inhibition assay was performed for DA quantification.

Main Results:

• The developed biosensor demonstrated a linear dynamic range for DA detection from 85 pg/ml to 700 ng/ml.
• The biosensor exhibited high specificity towards DA, with no significant interference from ascorbic acid (AA), uric acid (UA), DOPAC, or DOPA.
• The sensor surface showed excellent stability through repeated regeneration and affinity reaction cycles.

Conclusions:

• The study presents a simple, effective, and stable bioaffinity sensor for dopamine detection.
• The use of a natural receptor (DA-RC) offers a promising approach for DA sensing.
• This biosensor holds potential for the development of portable systems for clinical and medical diagnostics.