Manufacture and characterization of indicator electrodes from PPy + H2SO4 and PPy + Sulfonic acid as a urea sensor using urease enzyme immobilization technique in PVA

Research has been carried out on indicator electrodes (1) PVA-Enzyme/PVC-KTpClPB, sensitivity 19,069 mV/decade, detection range 1.10⁻⁵–5.10⁻⁴ M, detection limit 1.10–5 M. The width of the peak UV–vis absorbance is narrow (2) PVA-Enzyme/GA-2.9 %/PVC-KTpClPB wide UV–vis absorbance peak but the absorbance peak decreased, (3) PVA-Enzyme/GA-2.9 %/PVC-KTpClPB-o-NPOE XRD analysis amorphous spectral pattern appeared (4) PVA-Enzyme/GA-2.9 %/PPy + H₂SO₄/PVC-KTpClPB-o-NPOE (5) PVA-Enzyme/GA-2.9 %/PPy + Sulfonic Acid/PVC-KTpClPB-o-NPOE, amorphous spectrum pattern in (4) and (5) were greatly reduced for the enzyme variation of 0.6 g in 0.5 mL (50 % water + 50 % alcohol). GA plays a role in increasing the detection range, o-NPOE forms amorphous, enzyme variations increase the intensity of the XRD spectrum pattern. The method of developing a gradual modification of the indicator electrode membrane by cross-linking GA, o-NPOE, conductive polymer. The best results were obtained at the indicator electrode PVA-Enzyme/GA-2.9 %/PPy + Sulfonic Acid/PVC-KTpClPB-o-NPOE. Analysis of the linear curve of the sample EI₅-1 with a sensitivity of 41.56 mV/decade, a detection range of 10⁻⁴–10⁻¹ M and a detection limit of 10⁻⁴ M, R² = 97.51 %. The best indicator electrode is EI₅-1.