An amperometric biosensor based on multiwalled carbon nanotube-poly(pyrrole)-horseradish peroxidase nanobiocomposite film for determination of phenol derivatives

Electrochemical Biosensor with pH Regulation of CNTs/HRP Multilayer for Phenols

“…The sensitivity was 0.00554 A·L/mol, which was much higher than the sensitivities listed in the references of CNTs-based HRP modified electrodes. 25,26 For instance, the sensitivity is 50 nA·L/cm 2 ·μmol in Ref. 26 and is 176 nA·L/cm 2 ·μmol in this study (electrode diameter 2 mm).…”

“…The difference in sensitivity of phenolics might depend on the electron-donor conjugation of a substituent in substrates. 25 In the cases of o-aminophenol, catechol, hydroquinone, and o-chlorophenol, they can easily form the corresponding conjugation structures; in the case of o-cresol, however methyl groups of o-cresol do not encourage the formation of the conjugation structures. Thus the sequences of sensitivites of phenolics are as shown in Table 1.…”

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

“…Consequently, very intensive studies have been conducted to develop innovative methods of detection, improving current ones based on chemical analysis, these last ones being time-consuming and requiring usually pretreatment steps. In this context, many biosensors have been developed for phenol determination using different enzymes: superoxide dismutase [6], laccase [7], [8], and horseradish peroxidase [9]- [11] … Fungal tyrosinases are also widely used, these enzymes catalyzing the oxidation of monophenols and o-diphenols to quinones in the presence of oxygen [12]. 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].…”

“…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.…”

Fabrication of Gold Nanoparticles/Polypyrrole/HRP Electrode for Phenol Biosensor by Electropolymerization

“…resins and plastics, petroleum refining, food, pharmaceuticals, and pesticides [1]. Among several methods of analyses, biosensors are promising tools for detecting phenol and its derivatives due to their simplicity, high sensitivity, ease of use, and suitability for on-site monitoring [2].…”