Linamarin sensors: amperometric sensing of linamarin using linamarase and glucose oxidase

• Published in: Journal of electroanalytical chemistry (Lausanne, Switzerland) Switzerland), 1996-05, Vol.407 (1), p.155-159
• Main Authors: Tatsuma, Tetsu, Tani, Koichiro, Oyama, Noboru, Yeoh, Hock-Hin
• Format: Article
• Language: English
• Subjects: Amperometric sensors; Biological and medical sciences; Biosensors; Biotechnology; Chemistry; Electrochemistry; Electrodes: preparations and properties; Enzyme-modified electrodes; Exact sciences and technology; Fundamental and applied biological sciences. Psychology; General and physical chemistry; Ion selective electrodes; Linamarin; Methods. Procedures. Technologies; Various methods and equipments
• ISSN: 1572-6657; 1873-2569
• DOI: 10.1016/0022-0728(95)04504-X

Amperometric sensors for linamarin, a cyanogenic glycoside, were fabricated. They were based on the detection of glucose liberated from the hydrolysis of linamarin by linamarase from cassava leaf. A linamarase-glucose oxidase bienzyme-modified SnO 2 electrode was observed to function at +900 mV vs. Ag | AgCl in a hydrogen peroxide detection mode, and could determine linamarin down to 10 μM. In contrast, a linamarase-glucose oxidase bienzyme-modified graphite electrode mediated by poly( N-isopropylacrylamide- co-vinylferrocene) responded to greater than 0.2 mM linamarin at +500 mV vs. Ag | AgCl. A linamarase-glucose oxidase-peroxidase trienzyme electrode was also fabricated by coating a peroxidase-incorporated polypyrrole-modified SnO 2 electrode with a linamarase-glucose oxidase cross-linked film. This trienzyme electrode, which is the most practical linamarin sensor, was able to function at a mild potential of +150 mV vs. Ag | AgCl, and has a sensitivity of 5 μM linamarin.