Diazonium-functionalized tyrosinase-based biosensor for the detection of tea polyphenols

Efficient Immobilization of Tyrosinase Enzyme on Layered Double Hydroxide Hybrid Nanomaterials for Electrochemical Detection of Polyphenols

“…Based on this estimation, we obtain a linear range of 0-2.4 μM, leading to the conclusion that it is particularly well-adapted to the detection of low concentrations (typical limits of detection and linear ranges usually range from nM to hundreds of μM in the case of tyrosinase-based biosensors [16]- [18], [20]- [25], [27], [28], [63], [65]. In the context of tea polyphenol detection, our maximal concentrations for a linear biosensor response are in agreement with those obtained in tea decoctions, which are around 2-5 μM [17].…”

“…These biosensor features correspond to averages, since obtained with a mixture of polyphenols extracted from green tea. Indeed, biosensor efficiency should vary with the nature of polyphenols, as described in literature [17]- [19], [22], [23], [30], [40], [58], [63]- [65]. However, it is possible to determine a mean molecular mass of polyphenols at 415 g.mol −1 , by taking into account the molar mass of each compound present in the mixture and its relative percentage determined from previous analyses [44].…”

“…They present indeed attractive properties: effectiveness in biosynthesis, capacity of phenols removal from various samples and high capacity of detection and quantification of phenols [13]. In addition, the detection by tyrosinase-based biosensors is not limited to pure phenol compounds, some biosensors showing their efficiency in the case of more complex mixtures of polyphenols such as those found in tea extracts [14]- [17].…”

“…Different approaches have been developed for the immobilization of tyrosinase: silica sol-gel composite films [18], tyrosinase-modified boron-doped diamond electrodes [19], [20], tyrosinase entrapped in an agarose-guar gum [21], glassy carbon electrode modified by gold nanoparticles [22], tyrosinase-FeO 3 nanoparticles-chitosan [23], use of polyaniline-carbon nanofibers or nanotubes [24]- [27], diazonium salt [17] or titania sol-gel matrix [28] … Among host matrixes already used for the immobilization of enzymes recognizing polyphenols [6]- [11], [18]- [30], Layered Double Hydroxide (LDH) nanomaterials are attractive candidates for electrochemical analysis in general and for enzyme immobilization [31], [32], since they exhibit many advantageous features in the development of hybrid biomaterials. LDHs are an unusual family of layered materials consisting of positively charged layers with charge balancing anions inserted between these layers.…”

Molybdenum disulphide and graphene quantum dots as electrode modifiers for laccase biosensor

“…In recent years, laccase based biosensors are becoming relevant for areas like food analysis and environmental monitoring due to their properties such as fast response time, low-cost, low reagents consumption and the most important one, the possibility to use them in field. The ability of laccase to catalyse the one-electron oxidation of different polyphenols has been used to develop laccase based electrochemical biosensors for the determination of polyphenolic index in wines (García-Guzmán et al, 2015;Lanzellotto et al, 2014), in tea infusions (Cortina-Puig et al, 2010;Eremia et al, 2013) and tea leaves extracts (Rawal et al, 2012) as well as for the determination of environmental pollutants (Brondani et al, 2013;Nazari et al, 2015;Oliveira et al, 2013).…”