Selective flow-injection determination of methanol in the presence of ethanol based on a multi-enzyme system with chemiluminescence detection

✍ Scribed by Yoshiie Sekine; Masayasu Suzuki; Toshifumi Takeuchi; Eiichi Tamiya; Isao Karube

• Publisher: Elsevier Science
• Year: 1993
• Tongue: English
• Weight: 482 KB
• Volume: 280
• Category: Article
• ISSN: 0003-2670
• DOI: 10.1016/0003-2670(93)85119-5

✦ Synopsis

A highly selective flow-injection system was developed for the determination of methanol. The system consisted of three immobilized enzymes with luminol chemiluminescence detection. First, methanol was oxidized in the presence of alcohol ozidase to yield formaldehyde and hydrogen peroxide. The hydrogen peroxide produced was then destroyed by catalase. The formaldehyde formed in the first stage was further oxidized by NAD+-formaldehyde dehydrogenase. The NADH formed was oxidized by 1-methozy-5-methylphenazinium methylsulphate (l-MPMS), and finally the reduced I-MPMS was spontaneously oxidized and hydrogen p&ozide was produced. The concentration of tbe hydrogen peroxide produced, which was proportional to the initial concentration of methanol, was determined by luminol chemiluminescence. The determination range was from 0.1 to 100 mg 1-l and the response time was less than 2 min per sample with a relative standard deviation of less than 3%. The system showed good selectivity for methanol; the response was ca. 50 times higher than for ethanol.