Abstract
Turbidimetric or light scattering assays can be used to determine the extent of aggregation in protein formulations. Using low molecular weight urokinase (LMW-UK) as a model protein, the effect of polymeric additives on heat-induced aggregation was evaluated. Previous work has shown that under 60°C heat treatment, LMW-UK initially denatures and the unfolded protein associates to form soluble aggregates. Eventually, these aggregates associate to form a precipitate. The effects of polymers on the initial aggregation phase was examined. Hydroxyethyl (heta) starch, polyethylene glycol 4000, and gelatin were found to be effective, concentration-dependent inhibitors of aggregation, whereas polyvinylpyrrolidone (PVP) and polyethylene glycol 300 were ineffective. Overall, the effect of polymeric additives on the stability of thermally-stressed LMW-UK can be accounted for by preferential exclusion of the solute from the surface of the protein.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 1004-1008 |
| Number of pages | 5 |
| Journal | Pharmaceutical Research: An Official Journal of the American Association of Pharmaceutical Scientists |
| Volume | 11 |
| Issue number | 7 |
| DOIs | |
| State | Published - Jul 1994 |
Keywords
- additives, polymeric
- aggregation
- formulation
- protein stability
- turbidimetry
- urokinase
ASJC Scopus subject areas
- Biotechnology
- Molecular Medicine
- Pharmacology
- Pharmaceutical Science
- Organic Chemistry
- Pharmacology (medical)