Table 1.
Details and properties of some previously reported urea-based sensors
| Electrodes | Linear range (mM) | Sensitivity (µA·mM−1·cm−2) | Detection limit (mM) | Response time (s) | References |
|---|---|---|---|---|---|
| Ppy/Urs/polyion complex | 3× 103–3× 10−1 | – | 0.03 | 20 | 57 |
| PANI-Nf/Au/ceramic composite film | 1–10 | 4.2 | 1 | – | 25 |
| ITO/PaPcP/Urs | 0.16–5.02 | 0.47 | – | 40 | 54 |
| Ppy-Urs | 3.57×10−3−0.16 | – | 0.00214 | – | 55 |
| ITO/SG-PANI/Urs | 0.12–12.3 | 0.85 | 0.05 | ~5 | Present study |
Abbreviations: ITO, indium tin oxide; Nf, Nafion; PANI, polyaniline; PAPCP, poly(N-3-aminopropyl pyrrole-co-pyrrole); Ppy, polypyrrole; SG, sulfonated graphene; Urs, urease.