Table 3.
Characteristics of chip-based electrochemical O2 sensors.
| EC-Based O2 Sensor | LOD | Advantages | References |
|---|---|---|---|
| PDMS-container structure, and the glass substrate | 105 cells/mL | Short response time (6.9 s) | [83] |
| Low-temperature co-fired ceramic (LTCC) in an improved Clark-type DO sensor | Up to 8.1 mg/L | easy fabrication, flexible configuration, short response time (10.9 s), real-time detection | [84] |
| pHEMA hydrogel layer with electrolyte and PDMS as gas-permeable membrane | 0.121 μA cm−2 μM−1 | zero analyte consumption, 1-point calibration, long-term stability | [85] |
| PPy as the internal contact layer between polymeric sensitive membrane and gold | 0.11 ± 0.02 mg L−1 | Low cost, good performance and long-term potential stability | [86] |
| Multi-sensor glass-chip with a PDMS imprinted microfluidic channel grid | 100 pA per each 1% O2 | Transparent for microscopic observation, cheap, high sensitivity | [87] |
| Biocompatible glass chip fabricated using a hybrid thin film and laminate technologies | 0.735 μA μM−1 cm−2 | Low O2 consumption on the electrode, long-term stability | [88] |
| Biocompatible PDMS biochip with Au/Nafion electrodes | 50 mmol L−1 | real-time and continuous O2 monitoring in dynamic flow conditions | [89] |
| Kapton tape with embedded spirally rolled Microchannels | 12.89 nA mmHg −1 | O2 and temperature sensors, embedded spirally rolled microchannels | [90] |
| ElecCell technological platform using PVD | 6 pA/s | low-cost, easy to use and reproducible portable chip | [91] |
| ultra-microelectrode array (UMEA) | 0.49 nAs−0.5/mg/L | Ultra-short response time (<5 ms), 10 times lower O2 consumption | [92] |
| Multi-planar SPE sensor coupled with cultivation cell wells | 3 mg/L | Continuous long-term O2 measurement, sensor reutilization | [93] |
| Inkjet printing (IJP) DO sensors on the delicate porous substrate | 28 ± 1 nA L mg−1 | low O2 consumption on electrodes, short response time (60 s) | [94] |
| Electrochemical microsensors combined with spheroid technology | NM | fast, precise, and continuous long-term measurement of metabolic directly in the microwell | [95] |
| Spheroid on chip | NM | Real-time monitoring of metabolic activity and automated assays for toxicity evaluation | [96] |
NM: not mentioned.