Table 4.
Intrinsic dissolution rates of ketoconazole (KTZ) free base and its cocrystals with fumaric acid (KTZ-FUM) and succinic acid (KTZ-SUC) in unbuffered and buffered media at different pH.
| pH | Dissolution rate constant (μg.min-1.cm-2) | |||||
|---|---|---|---|---|---|---|
| Unbuffered media* | Buffers | |||||
| KTZ-FUM | KTZ-SUC | KTZ base | KTZ-FUM | KTZ-SUC | KTZ base | |
| pH 3 | 164 | 185 | 106 | 108 | 91 | 108 |
| pH 4 | 124 | 105 | 16 | 71 | 65 | 45 |
| pH 5 | 93 | 62 | -** | 51 | 48 | -** |
*pH of bulk media kept constant by adding HCl or NaOH solutions, as necessary
**Extremely low dissolution rate (practically zero) that could not be calculated with accuracy.