Table 1.
Summary of all animals used in this study.
| Animal groups | Rat no. | Days post-implant | Scanning electron microscopy (SEM) imaging | Electrophysiology | Histopathology | ||||
|---|---|---|---|---|---|---|---|---|---|
| Pre-implant | Post-explant | Impedance (MΩ) on day 1 | Impedance (MΩ) at euthanasia | Average array array yield (%) | Activated microglia (Yes/No) | Degenerated microglia (Yes/No) | |||
| Short-term implants(≤15 days) | F11 | 15 | Non-uniform insulation, cracks in insulation near recording tips | Bent tips, insulation delamination and cracks in insulation | 0.45 ± 0.14 | 0.689 ± 0.17 | 39.3 ± 32.8 | Y | Y |
| F12 | 7 | Crack in no. 1, some wires not straight, non-uniform insulation along wires | Cracks in insulation, insulation delamination, recessed insulation | 0.37 ± 0.12 | 0.504 ± 0.29 | 65 ± 28.1 | Y | Y | |
| F13 | 15 | Electrode tip not straight for no. 13, cracks along wire shank, some wires not straight | Insulation delamination in some electrodes, cracks in insulation | 0.41 ± 0.12 | 1.27 ± 0.43 | 78.1 ± 19.6 | Y | Y | |
| F14 | 7 | Electrode tip not straight for no. 16, cracks in insulation along shank | Broken tip, insulation delamination | 0.51 ± 0.68 | 0.494 ± 0.23 | 33.3 ± 20 | Y | Y | |
| F15 | 6 | No. 2 crack on recording surface, cracks in insulation along shanks, no. 8 wire tip not straight | Electrode tip not straight, some deinsulation | 0.4 ± 0.11 | 0.593 ± 0.22 | 81.2 ± 22.2 | Y | Y | |
| Chronic implants (≤6 months) | F9 | 71 | Majorly flawed: cracks in insulation at recording tips for most electrodes, non-uniform insulation | Cracks in insulation, insulation delamination, recessed insulation | 1.44 ± 0.59 | 0.947 ± 0.26 | 16.8 ± 22.4 | Y | Y |
| F10 | 21 | Cracks on electrode shanks, cracks in insulation at recording tips | Cracks, delamination, insulation damage | 0.47 ± 0.14 | 0.594 ± 0.19 | 4.8 ± 13.7 | Y | Y | |
| F2 | 180 | Non-uniform insulation on all wires, some wires not straight | Some bent tips, two electrodes have cracks in insulation | 0.61 ± 0.65 | 1.96 ± 0.71 | 74.3 ± 13.9 | Y | Y | |
| F4 | 180 | Irregular insulation, some wires not straight, tip missing for no. 6, bent recording tip no. 9 | Bent tips, insulation delamination | 0.397 ± 0.134 | 1.43 ± 0.49 | 40.5 ± 22.5 | N | N | |
| F6 | 180 | Bent tips for nos. 3, 4, 5, 9, and 13, some wires not straight, cracks in insulation | Insulation delamination on some wires, bent tips | 0.43 ± 0.2 | 0.7 ± 0.3 | 35.1 ± 19.6 | N | N | |
| F7 | 90 | Moderately flawed: bent tip no. 16, non-uniform insulation at recording tips, crack in insulation at tips | Insulation delamination in some electrodes, cracks, bent tips | 0.59 ± 0.7 | 1.47 ± 0.81 | 12 ± 8.6 | N | Y | |
| F8 | 91 | Majorly flawed: crack in recording tip no. 5, cracks in insulation of 8 electrodes, some wires not straight | Insulation delamination | 1.08 ± 0.24 | 2.14 ± 0.43 | 19.5 ± 21.4 | Y | Y | |
Animals are divided into short-term implants (≤2 week) and long-term implants (≤6 months). The table provides summarizes general abiotic and biotic observations.