Voltammetric determination of catalytic reaction parameters of laccase based on electrooxidation of hydroquinone and ABTS

A New and Sensitive Catalytic Resonance Scattering Spectral Assay for the Detection of Laccase Activity Using H2O2-I−-TDMAC System

“…A 0.48 U/mL and 0.80 U/mL laccase were determined 6 times, and both relative standard deviations were 2.8% and 1.7% respectively. Comparing with the assays reported, as inTable 2, [9][10][11][12][13] this RS assay was more sensitive. In addition, the reagents were easy to obtain.…”

“…[1][2][3][4] In the process of screening laccase strains, the laccase activity detection is required.5 Thus, a rapid and sensitive method for detection of laccase activity is necessary. Currently, several methods for detection laccase activity were reported such as oxygen electrode method, 6 microcalorimetry, 7 fluorescence spectrometry, 8 electrochemical method, 9,10 spectrophotometry [11][12][13][14] etc. The commonly used method for the detection of laccase activity is spectrophotometric assay due to its simple operation.…”

Biocathodes for Dioxygen Reduction in Biofuel Cells

“…This compound has been known for a long time as a good mediator for laccase [26]. The redox potential of ABTS 2À/.À redox couple is low enough to provide reasonable driving force for dioxygen electroreduction catalyzed by laccase [6,194] and bilirubin oxidase [195]. Although the formed anion radical slowly deactivates laccase [196][197][198], this mediator is frequently used as a "model" system.…”

“…Quinones or watersoluble ferrocene derivatives dissolved in aqueous solution were tested with laccase present in solution [194], covalently bonded to self-assembled monolayers of mercaptoundecanoic or mercaptopropionic acids [86], and encapsulated in monoolein cubic phases [179,182] or poly(N-isopropylacrylamide) gel [148]. The film, formed by gel comprising MWCNT and room-temperature ionic liquid, served as host for laccase or bilirubin oxidase and ferrocene mono-or dicarboxylic acids [98,99].…”

“…At pH 5.1 catalytic current also reaches 0.5 mA/cm 2 . It is much larger than that detected for laccase bound to the organothiol monolayer-modified electrodes, pointing to better-oriented biocatalyst molecules on the surface [194,219,223]. The current density decreases at high ionic strength [217], which shows that electrostatic interactions between positively charged attached amino groups and negatively charged regions of the protein surface play an important role in orienting laccase during immobilization (see Fig.…”