The behavior of the enzyme acetylcholinesterase was studied at the air/water interface. Surface pressure-area (π-A) isotherms and UV-vis spectra recorded at different surface pressures were determined for different salt concentrations in the subphase. The ionic strength of the subphase does not influence the physical properties in consideration; however, the pH of the subphase has a great effect on its surface and optical properties. A subphase at pH 6.5 has shown that the enzyme is highly stable, based on the π-A compression/decompression isotherms. No changes in the area per molecule were observed when the surface pressure was maintained constant at 16 mN/m for a period of 120 min. The long-term stability of acetylcholinesterase at the air/water interface was demonstrated for pH 6.5 and a salt concentration of 10-2 M (KCl). The absorption spectra of the monolayer, measured directly at the air/water interface, are considered good evidence of the organization of the enzyme molecules.
- Interfacial properties
- Spectroscopic property
ASJC Scopus subject areas
- Colloid and Surface Chemistry
- Physical and Theoretical Chemistry
- Surfaces and Interfaces