TABLE 2.
Parameters for RSeal, ITail, cell capacitance, RSeries, Rundown, Vhalf, and IC50 values for HEK cells expressing hERG for standard internal and fluoride-free internal solution.
| Parameter | Standard internal | Fluoride-free internal |
| RSeal (GΩ) | 2.23 ± 0.02 (2155) | 1.36 ± 0.02 (3123)* |
| ITail (nA) | 0.70 ± 0.01 (3175) | 0.99 ± 0.01 (4192)*** |
| Capacitance (pF) | 16.2 ± 0.3 (387) | 15.9 ± 0.4 (313) |
| RSeries (MΩ) | 8.6 ± 0.2 (379) | 10.2 ± 0.2 (317)*** |
| Rundown over 18 min (%/min) | 0.10 ± 0.05 (58) | 0.07 ± 0.07 (42) |
| Vhalf (mV) | −93.0 ± 0.5 (190) | −92.1 ± 2.3 (261) |
| IC50 Terfenadine (nM) | 237 ± 26 (52) | 337 ± 53 (17) |
| IC50 Verapamil (nM) | 394 ± 17 (54) | 457 ± 37 (29) |
RSeal values > 4 GΩ could not be accurately calculated, therefore only RSeal ≤ 4 GΩ were used for the calculation of the mean. Shown are mean ± S.E.M, number of cells shown in parentheses.
*P < 0.05, ***P < 0.001, unpaired Student’s t-test.