Membran dalaman yang selektif bagi biosensor glukosa amperometrik telah dipilih secara kuantitatif berdasarkan kepada sifat pengangkutannya. Disk elektrod yang berputar digunakan untuk mendapatkan kebolehtelapan asetaminofen, satu penganggu yang biasa bagi biosensor glukosa berdasarkan peroksid, dan hidrogen peroksid melalui poli(vinil alkohol)(PVA) tersambung silang. Kesemua amali resapan dilakukan menggunakan elektrod berputar emas kerana elektrod platinum mempamerkan perpindahan elektron yang perlahan pada permukaannya ketika oksidasi asetaminofen yang menyebabkan ia tidak sesuai digunakan. Kememilihan PVA tersambung silang kepada peroksid adalah berasaskan kebolehtelapan peroksid berbanding keboletelapan asetaminofen. Peroksid mempunyai saiz yang kecil. Oleh itu kebolehtelapannya hanya terkesan bila saiz jejaring PVA tersambung silang dikurangkan dengan ketara. Keboletelapan asetaminofen yang bersaiz lebih besar pula adalah berkadar terus dengan saiz jejaring PVA tersambung silang. PVA tersambung silang didapati mempamerkan kememilihan yang sederhana terhadap peroksid.
Kata kunci: Biosensor glukosa; gangguan; asetaminofen; kebolehtelapan; poli(vinil alkohol) tersambung silang
The internal selective membrane for an amperometric glucose biosensor was selected quantitatively based on its transport properties. A rotating disk electrode was used to obtain the permeability of acetaminophen, a common interferent for peroxide–based glucose biosensor, and hydrogen peroxide through cross–linked poly(vinyl alcohol) (PVA). All diffusion experiments were performed using a gold rotating electrode as platinum electrode exhibited slow electron transfer on its surface during the oxidation of acetaminophen, thus rendering it ineffective for this work. Selectivity of crosslinked PVA to peroxide was based on the permeability of peroxide compared to that acetaminophen. As hydrogen peroxide is small, its permeability was only affected when the mesh size of cross–linked PVA was significantly reduced. The permeability of the bigger acetaminophen, on the other hand, was linearly proportional to the mesh size of the cross–linked PVA. Cross–linked PVA membrane was found to display marginal selectivity towards peroxide.
Key words: Glucose biosensor; interference; acetaminophen; permeability; cross–linked poly(vinyl alcohol)
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