Table 2 Comparison of the reported electrodes (sensors) with the proposed ammonium sensor
Recognition element | Transducing mode | Linear range (mol L−1) | Dynamic range (mol L−1) | Sensitivity | DL (mol L−1) | Response time | Storage stability | Ref. |
|---|---|---|---|---|---|---|---|---|
Nonactin in self-plasticizing poly(n-butyl acrylate) film | Potentiometric | 1 × 10−5–1 × 10−1 | – | 59 mV decade−1 | 1.0–4.0 × 10−6 | – | At least 3 months | [13] |
Glutamate oxidase and glutamate dehydrogenase | Amperometric | 1 × 10−5–3 × 10−4 | 1 × 10−5–3.1 × 10−4 | 325.87 nA s−1 mM−1 | 2.06 × 10−6 | 10 s | 18 days | [14] |
PANI/PSSMA (I) | Amperometric | 0–1 × 10−2 | – | 2.55 μA mM−1 | – | – | – | [15] |
PANI/PSSMA (II) | Amperometric | 0–1.25 × 10−2 | – | 12 μA mM−1 | – | – | – | |
Crown-ether end-capped carbosilane dendrimer (15-crown-5-functionalized carbosilane dendrimer) | Potentiometric | 7.60 × 10−6–1.0 × 10−1 | – | 53.3 mV decade−1 | 3.9 × 10−6 | 6–10 s | At least 45 days | [16] |
Pure culture of Nitrosomonas sp. | Amperometric | 1.4 × 10−4–1.43 × 10−3 | – | 0.030–0.036 n.s.r. | 1.4 × 10−4 | 15–25 min (in 5–6 days 10–15 min) | 14 days | [17] |
SiO2/ZrO2/phosphate-NH4 composite | Potentiometric | 1.0 × 10−6–1.0 × 10−2 | 7.7 × 10−7–4.0 × 10−2 | 31.3 mV decade−1 | 1.58 × 10−7 | 1 min | 6 months | [18] |
Poly(vinyl chloride) membrane with nonactin | Potentiometric | 1.0 × 10−5–1.0 × 10−1 | – | 56 mV decade−1 | 8.0 × 10−6 | 20 s | 6 months | [19] |
Zirconium titanium phosphate ion exchanger | Potentiometric | 1.0 × 10−4–1 | 1.2 × 10−5–1 | 42 mV decade−1 | 1.0 × 10−5 | 30 s | Over 2 years (if stored under controlled conditions). | [20] |
Copper ion-doped clinoptilolite | Amperometric | 2.0 × 10−5–1.0 × 10−3 | 2.0 × 10−5–1.0 × 10−2 | 191 μA mol−1 L | 5.0 × 10−6 | 1 min | – | [21] |
25,27-di-(5-thio-octyloxy)calix[4]arene-crown-6 | Conductometric | 1 × 10−5–1.5 × 10−3 | 1.0 × 10−5–1.0 × 10−2 | 8.22 μs mM−1 | 1.0 × 10−5 | 5–10 s | 115 days | This work |