Tyrosinase-Based Biosensors for Selective Dopamine Detection.

Area of Science:

• Electrochemistry
• Biosensor Technology
• Biomedical Engineering

Background:

• Dopamine (DA) detection is crucial for diagnosing neurological disorders.
• Existing detection methods often lack selectivity and sensitivity.
• Development of novel biosensors is needed for accurate DA monitoring.

Purpose of the Study:

• To develop a novel tyrosinase-based biosensor for selective dopamine detection.
• To enhance electrode selectivity using cobalt (II)-porphyrin (CoP) film.
• To validate the biosensor's performance in real biological samples.

Main Methods:

• Fabrication of a gold electrode modified with CoP film and cross-linked tyrosinase (Tyr).
• Electrochemical detection using differential pulse voltammetry to measure dopamine-quinone reduction current.
• Optimization of conditioning parameters for enhanced selectivity against ascorbic acid (AA).

Main Results:

• The CoP-modified electrode demonstrated improved selectivity for DA detection.
• A potential separation of 130 mV between AA and DA peaks was achieved.
• The biosensor exhibited a sensitivity of 1.22 ± 0.02 µA·cm^-2·µM^-1 and a detection limit of 0.43 µM.
• High recovery (96%) and low relative standard deviation (<5%) were observed in dopamine medication samples.

Conclusions:

• The developed tyrosinase-based biosensor offers selective and sensitive detection of dopamine.
• The CoP modification significantly enhances selectivity, enabling DA detection in complex matrices.
• The biosensor shows practical applicability for analyzing dopamine in human urine and blood serum.