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Highly sensitive biosensing of phenolic compounds using bioaccumulation/chronoamperometry at a tyrosinase electrode
Author(s) -
Wung Joseph,
Chen Qiung
Publication year - 1995
Publication title -
electroanalysis
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.574
H-Index - 128
eISSN - 1521-4109
pISSN - 1040-0397
DOI - 10.1002/elan.1140070811
Subject(s) - chronoamperometry , tyrosinase , chemistry , detection limit , biosensor , bioassay , amperometry , electrode , chromatography , enzyme , cyclic voltammetry , electrochemistry , organic chemistry , biochemistry , biology , genetics
Biocatalytic accumulation is used to greatly enhance the sensitivity of tyrosinase enzyme electrodes for phenolic compounds. By allowing the enzymatic reaction to proceed for different time periods (under open‐circuit conditions) it is possible to accumulate the quinone product near the transducer surface. The subsequent chronoamperometric response is substantially higher than analogous bioassays without accumulation. For example, with 3 min accumulation, a 28‐fold signal amplification is observed. Assays of microliter (40 μL) samples are reported, yielding a detection limit of 2 × 10 −8 M (88 pg) catechoi following a 3 min accumulation. The influence of various experimental variables is explored. Applicability to bioassay of relevant environmental samples is illustrated.