An Enzyme Electrode Based on Lipoxygenase Immobilized in Gelatin for Selective Determination of Essential Fatty Acids

Figures & data

Figure 1. Effect of pH on the electrode response (pH 4.0–5.0: acetate buffer, pH 6.0–8.0: phosphate buffer, pH 9.0–10.0: borate buffer; LA: 64.2 µM, ALA: 7.5 µM, 30°C).

Figure 2. Effect of temperature on the electrode response (LA: 64.2 µM, in borate buffer, 0.2 M, pH 9.0).

Figure 3. Calibration graph for LA (in borate buffer; 0.2 M, pH 9.0, at 30°C).

Figure 4. Calibration graph for ALA (in borate buffer; 0.2 M, pH 9.0, at 30°C).

Figure 5. Calibration graph for ALA (second oxygenation conditions: in phosphate buffer; 0.2 M, pH 6.0, at 30°C).

Table 1. The Signals (ΔDO) from First Oxygenation of LA in the Presence of ALA

LA conc. (µM)	ΔDO(mg/l) (for LA)	ΔDO(mg/l) (for ALAa)	ΔDO(mg/l) (for LA + ALA)
12.84	0.03	0.04	0.07
32.10	0.07	0.04	0.10
64.2	0.12	0.04	0.16
96.3	0.16	0.04	0.19

^aALA conc: 3.8 µM.