Tyrosinase-Based Biosensors for Selective Dopamine Detection

Abstract

A novel tyrosinase-based biosensor was developed for the detection of dopamine (DA). For increased selectivity, gold electrodes were previously modified with cobalt (II)-porphyrin (CoP) film with electrocatalytic activity, to act both as an electrochemical mediator and an enzyme support, upon which the enzyme tyrosinase (Tyr) was cross-linked. Differential pulse voltammetry was used for electrochemical detection and the reduction current of dopamine-quinone was measured as a function of dopamine concentration. Our experiments demonstrated that the presence of CoP improves the selectivity of the electrode towards dopamine in the presence of ascorbic acid (AA), with a linear trend of concentration dependence in the range of 2–30 µM. By optimizing the conditioning parameters, a separation of 130 mV between the peak potentials for ascorbic acid AA and DA was obtained, allowing the selective detection of DA. The biosensor had a sensitivity of 1.22 ± 0.02 µA·cm−2·µM−1 and a detection limit of 0.43 µM. Biosensor performances were tested in the presence of dopamine medication, with satisfactory results in terms of recovery (96%), and relative standard deviation values below 5%. These results confirmed the applicability of the biosensors in real samples such as human urine and blood serum.

Electrochemical Biosensors Containing Pure Enzymes or Crude Extracts as Enzyme Sources for Pesticides and Phenolic Compounds with Pharmacological Property Detection and Quantification

“…Aranganathan et al [33] reported the use of tyrosinase for detection of 3,4-dihydroxy-l-phenylalanine (l-DOPA), which is a preferred drug for the treatment of Parkinson's disease. Florescu and David [34] developed a tyrosinase-based biosensor for selective dopamine detection, in which its selectivity was increased by employing cobalt (II)-porphyrin (CoP) film-modified gold electrodes. It operates by enabling the direct immobilization of the enzyme layer in more available sites, acting as an electrochemical mediator during enzyme-catalyzed reaction, leading to a complete recovery of the electrode, with no effect on the detection limit [34].…”

“…Florescu and David [34] developed a tyrosinase-based biosensor for selective dopamine detection, in which its selectivity was increased by employing cobalt (II)-porphyrin (CoP) film-modified gold electrodes. It operates by enabling the direct immobilization of the enzyme layer in more available sites, acting as an electrochemical mediator during enzyme-catalyzed reaction, leading to a complete recovery of the electrode, with no effect on the detection limit [34]. Tyrosinase can be used as a pesticide detector as well.…”

Enzymatic Platforms for Sensitive Neurotransmitter Detection

“…The method described here was based on original polymers, which acted as a matrix for enzyme immobilization (stable matrix for a protein anchoring, which also ensured stability during measurements), detection based on an enzyme-dependent redox reaction and electrochemical measurements, and presented a highly sensitive, quick, and simple analytical procedure. However, the main advantage over the other systems known from the literature is the low detection limit in comparison with other systems [25][26][27] and excellent selectivity. The fabricated gold and platinum electrodes modified with semiconducting polymers (poly[2,6-bis(3,4-ethylenedioxythiophene)-4-methyl-4-octyl-dithienosilole], poly[2,6-bis(selenophen-2-yl)-4-methyl-4-octyl-dithienosilole)]), and laccase or horseradish peroxidase (HRP) exhibited exquisite electrochemical behavior and direct electron transfer was achieved.…”

In Situ Laser-Induced Fabrication of a Ruthenium-Based Microelectrode for Non-Enzymatic Dopamine Sensing

“…As a rule, the electrochemically based techniques operate either in an enzymatic or in a non-enzymatic regimen [11]. Despite decent specificity, enzymatic sensing of dopamine has a number of limitations, such as low accuracy of detection, poor reproducibility and low stability as a result of enzyme decomposition (typically, tyrosinase) [12], and being subject to influence of the environment (pH and temperature) [11]. In contrast, in the enzyme-free mode, direct detection of dopamine is ensured by catalysis of ox-red reactions of this analyte occurring on the surface of an electrode [13].…”