Table 6.
Critical physicochemical and biological attributes, validated analytical methods and quality specifications.
| CQA | Method | Quality specification (acceptance limit) |
|---|---|---|
| Appearance | Organoleptic inspection | Opalescent white suspension that slowly tends to form a white deposit, easily re-suspended by shaking. Characteristic odor of Thimerosal |
| pH | Potentiometry (USP 42) | 6.0–7.2 |
| Adjuvant content (Al3+) | Complexometry | 1.5–3.5 mg/mL |
| Thiomersal content | Spectrophotometry, Biologicals (1995) 23, 65–69 | 0.07–0.13 mg/mL |
| Total protein content | Modified Lowry1 | (100 ± 30) µg/mL, total protein content must be within a value ± 30% of the theoretical calculated value |
| Adsorption percent | Modified Lowry, Lowry O.H. et al. J. Biol. Chem. 193:265–275, 1951 | ≥ 70% |
| Osmolality | Osmometer | – |
| Volume | Using separate syringes | Not less than stated amount |
| RBD identity | SDS-PAGE and Immonoblotting (immunoenzymatic assay) | Positive recognition, i.e. dot intensity of sample of final product equal or higher than positive control |
| Endotoxin content | Chromogenic LAL Test2 | > 100 EU/mL |
| Sterility | Culture- Membrane filtration method (USP 29) | Absence of viable microorganism |
| Abnormal toxicity | Injection into laboratory animals | None of the animals show any weight loss and toxic signs at the end of the observation |
1Lowry Protein Assay.
2LAL: limulus amebocyte lysate.