An Enzyme Electrode Based on Lipoxygenase Immobilized in Gelatin for Selective Determination of Essential Fatty Acids
Abstract
An enzyme electrode for the specific determination of ω‐3 and ω‐6 fatty acids from the mixture of essential fatty acids (EFAs) was developed by using lipoxygenase (LOX) (EC 1.13.11.12) from soy beans in combination with a dissolved oxygen (DO) probe. The enzyme electrode showed different sensitivities for linoleic (LA) and α‐linolenic acids (ALA), the most common essential fatty acids. Enzyme electrode response depends linearly on LA concentration between 12.8–160.5 µM and ALA concentration between 3.8–18.9 µM in borate buffer, 0.2 M at pH 9.0. However, in phosphate buffer 0.2 M at pH 6.0 linearity is in the range of 7.5–22.5 µM of ALA concentration at 5 minutes response times. Moreover, maximum electrode response was found in borate buffer at pH 9.0 and 30°C.