Abstract
1. 1. The force area characteristics of monolayers of 3β-, 3α-hydroxysterols and ketosteroids have been studied. 2. 2. The 3β-hydroxysterols cholesterol, cholestanol, lathosterol, 7-dehydrocholesterol, and B-norcholesterol are perpendicularly oriented at the air-water interface and show high collapse pressures. Ergosterol, stigmasterol, and androstan-3β-ol demonstrate a similar behavior at high pressures, but the collapse pressure is reduced. The cis-structured coprostanol shows an increased area per molecule. 3α-Hydroxysterols (epicholesterol and androstan-3α-ol) reveal strongly reduced collapse pressures when compared with the respective 3β-hydroxysterols. All ketosteroids show high areas per molecule. 3. 3. The force-area curves show little temperature effect. 4. 4. The interaction of 18:1/18:0 lecithin with sterols is dependent on: (a) planar sterol nucleus, (b) 3β-hydroxy group, (c) intact side chain. 5. 5. Besides 3β-hydroxysterols, 3α-hydroxysterols and ketosteroids can also show some condensation effect. However, minimal area per molecule can be achieved only with 3β-hydroxysterols. 6. 6. The interaction of lecithin and sterol in monolayers is governed by a number of factors including van der Waal's interactions, but also hydrogen bonding between the 3β-hydroxy group and environment is considered to be important.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: Biochimica et Biophysica Acta (BBA) - Biomembranes
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
