Table 2.
Characteristics of most frequently-used metal oxides in prospective biosensors.
| Metal-oxides | IEP | Availability of enzymatic/nonenzymatic sensor | Compatibility with CNT | Compatibility with conducting polymer, metal nanoparticle | Application for other biosensors | Reference |
|---|---|---|---|---|---|---|
| ZnO | 9.5 | available/ N/A | available | N/A, Co | H2O2, gas, cholesterol | [84,88,91,100,225] |
| CuO | 6.5 | available/available | available | N/A, Pd(IV) | H2O2, carbohydrates, gas | [112,113,118,119] |
| MnO2 | 4–5 | available/available | available | available, N/A | ascorbic acid, H2O2, Li+ | [133,134,135,226] |
| TiO2 | 3.9–8.2 | available/N/A | available | available, Pt | H2O2, DNA hybridization, gas | [137,157,227] |
| CeO2 | ∼9 | available/ N/A | N/A | N/A | DNA hybridization, H2O2 | [167,170–172,176] |
| SiO2 | 1.7–3.5 | available/N/A | available | N/A | H2O2, biomolecules, urea, penicillin | [56,186,187,191] |
| ZrO2 | 4.15 | available/ N/A | N/A | N/A | H2O2, gas | [196,200,228] |
*
N/A= Not available