Development of an enzymeless biosensor for the determination of phenolic compounds

✍ Scribed by Maria Del Pilar Taboada Sotomayor; Auro Atsushi Tanaka; Lauro Tatsuo Kubota

• Publisher: Elsevier Science
• Year: 2002
• Tongue: English
• Weight: 247 KB
• Volume: 455
• Category: Article
• ISSN: 0003-2670
• DOI: 10.1016/s0003-2670(01)01608-7

✦ Synopsis

The construction of amperometric enzymeless biosensors for phenolic compounds determination, using carbon paste electrode modified with copper phtalocyanine (CuPc) and histidine (His), based on the chemistry of the dopamine ␤-monooxygenase (D␤M) enzyme that catalyzes the hydroxylation of the dopamine and its analogs is shown. The modified carbon paste was evaluated on electrodes constructed in two ways: putting the paste into a cavity of a rotating disk electrode and a platinum slide electrode fixed into a glass tube. The sensor in hydrodynamic conditions presented a linear response range between 30 and 250 mol l -1 , with a sensitivity of 4.6 ± 0.1 nA l mol -1 cm -2 for catechol, response time of 3 s and lifetime of about 50 days when stored at room temperature. The sensor in static conditions showed a linear response range from 40 to 250 mol l -1 , with a sensitivity of 0.30 ± 0.01 nA l mol -1 cm -2 for catechol. The sensors presented the following relative response order for dopamine and some analog species: catechol > dopamine > guaiacol > serotonin > phenol.