Multiwalled Carbon Nanotube‐CaCO₃ Nanoparticle Composites for the Construction of a Tyrosinase‐Based Amperometric Dopamine Biosensor

Abstract

We report the fabrication of a highly sensitive dopamine biosensor based on the entrapment of tyrosinase into CaCO3 nanoparticles at Multiwalled Carbon Nanotube (MWCNT) electrodes. CaCO3 acts as host matrix for tyrosinase and MWCNT provides a highly porous conductive network enhancing the enzyme immobilization and the electrochemical transduction of the enzyme reaction by boosting the amplification phenomenon involved in the biosensing of catechol and dopamine. The comparison of the performance of CaCO3‐tyrosinase electrodes with and without MWCNT film clearly indicates the improvement in sensitivity and maximum current brought by the combination of MWCNTs and inorganic nanomaterials. These nanostructured hybrid bioelectrodes exhibit a high sensitivity for the detection of catechol and dopamine, namely 35.7 A mol−1 L cm−2, the detection limit for dopamine being 15 nmol L−1 with no influence of the presence of interferents, i.e. uric acid and ascorbic acid.

Highly Selective Room‐Temperature Catalyst‐Free Reduction of Alkaline Carbonates to Methane by Metal Hydrides

“…On the basis of previous investigations, we think that the replacement of gaseous CO 2 and H 2 with solid alkaline carbonates and MHs to achieve CO 2 methanation and the synthesis of CO x ‐free hydrogen/methane fuel mixtures have many inherent advantages. First, alkaline carbonates, especially for CaCO 3 , are abundant, inexpensive, safe, and easy to handle . Second, metal carbonate–MH systems are better suited for fuel storage and in situ fuel preparation as they are easy to store and transport and have a high volumetric energy density.…”

Design of a reduced-graphene-oxide composite electrode from an electropolymerizable graphene aqueous dispersion using a cyclodextrin-pyrrole monomer. Application to dopamine biosensing

“…It is noteworthy that tyrosinase was also electrodeposited on two to ten layers of poly-[β-CD-pyrrole/RGO], but these electrodes did not show any biosensing performance enhancement. This effect can be attributed to the steric hindrances induced by thick electropolymerized films towards the permeation of both substrate and oxygen, despite the higher electroactive area [15]. sensing where sensitivity and LOD were improved at these graphene-based electrodes.…”

“…We and others have recently demonstrated that three-dimensional bio-functionalized architectures enhance biosensing performances [15]. In particular, the use of carbon nanotube supports provides a combination of high electroactive area, high stability and high conductivity [16,17].…”

Electrochemical Activity Determination of Catechol‐O‐methyl Transferase by Selective Dopamine Detection

“…Hence, numerous sensor applications for dopamine apply glassy carbon, screen-printed carbon or carbon paste electrodes. [25,26] A further increase of sensitivity of this kind of electrodes can be achieved by decoration of the electrode surface with nanomaterials such as carbon nanotubes, [27,28] nanocrystals, [29] graphene [30] or metal nanoparticles. [31] However, these carbon derived electrode materials show also some drawbacks for the detection of catecholamines.…”