Table 2.
Equilibrium solubility measured at different pHs and excipients by HPLC.
| Medium | Solubility (mg/mL) | ±SD |
|---|---|---|
| Hydrochloric (pH 2.5) | 25.97 | 0.920 |
| Hydrochloric (pH 5.0) | 3.92 | 0.090 |
| 1× PBS (pH 7.4) | 0.01 | 0.0001 |
| 0.1 M acetate buffer (pH 4.0) | 7.14 | 0.040 |
| 0.1 M acetate buffer (pH 4.5) | 2.29 | 0.020 |
| 0.1 M acetate buffer (pH 5.0) | 0.56 | 0.010 |
| 0.1 M citrate buffer (pH 4.0) | 0.06 | 0.001 |
| 0.1 M citrate buffer (pH 4.5) | 0.03 | 0.001 |
| 0.1 M citrate buffer (pH 5.0) | 0.02 | 0.001 |
| PEG 400 (20 %) | 8.01 | 0.330 |
| PEG 400 (40 %) | 8.80 | 0.140 |
| PEG 400 (60 %) | 9.48 | 0.430 |
| PEG 400 (80 %) | 12.55 | 1.800 |
| PEG 400 (100 %) | 15.49 | 0.380 |
| Cremophor EL (100 %) | 14.12 | 1.810 |
| Polysorbate 80 (100 %) | 8.46 | 1.190 |