Table 5.
DDDPlus™ parameters for intrinsic dissolution simulation
| Parameters | Metronidazole |
|---|---|
| Ingredient type | Active |
| Molecular weight (g/mol) | 171.1534 |
| Reference solubility (mg/mL) | 13.6 at pH 4.5 (measured via HPLC) |
| Density (g/mL) | 1.4535 |
| Precipitation time (s) | 900 (DDDPlus standard value) |
| Diffusion coefficient (cm2/s⋅105) | 1.037 (calculated via DDDPlus) |
| Reference logD | −0.02 at pH 7.436 |
| Mean radius (µm)/SD/no of bins | 333.06/2.5/8 (not used in intrinsic dissolution) |
| Dissolution model | Intrinsic dissolution |
| pKa table/solubility-pH data file (.spd) | |
| Solubility pH 1.0 (mg/mL) | 30.610 |
| Solubility pH 3.0 (mg/mL) | 14.110 |
| Solubility pH 5.0 (mg/mL) | 12.810 |
| Solubility pH 7.0 (mg/mL) | 11.610 |
| General properties | |
| Compression force (kN) | 19.9 (from manufacturing) |
| Tablet diameter (mm) | 8.5 (from manufacturing) |
| Optimized metronidazole calibration constant | |
| SGFsp | 0.3564 |
| Acetate buffer pH 4.5 | 0.2330 |
| 10% sucrose | 0.2270 |
| 20% sucrose | 0.1910 |
| 30% sucrose | 0.1471 |
Abbreviations: DDDPlus, Dose Disintegration and Dissolution Software; HPLC, high-performance liquid chromatography; SD, standard deviation; SGFsp, simulated gastric fluid sine pepsin.