It is shown that in the process of measuring the contact angles of drops of water or of air bubbles at biological surfaces transfer of natural surface-active materials to the air /water interface occurs with a consequent large reduction in the surface tension. The estimates of cell surface tensions from contact angles based on theoretical calculations in which the air/water tension of pure water is used are consequently in error. The adhering bubble method is preferable for contact angle determinations in biological systems.
All Science Journal Classification (ASJC) codes
- Materials Science(all)
- Condensed Matter Physics
- Surfaces and Interfaces