Chemical Research in Chinese Universities ›› 2016, Vol. 32 ›› Issue (2): 242-247.doi: 10.1007/s40242-016-5410-5

• Articles • Previous Articles     Next Articles

Influence of K+, Na+ or Ca2+ Ions on the Interaction Between AmB and Saturated Phospholipids by Langmuir Technique

WANG Juan, SUN Runguang, LI Junhua   

  1. Laboratory of Biophysics and Biomedicine, College of Physics and Information Technology, Shaanxi Normal University, Xi'an 710062, P. R. China
  • Received:2015-10-22 Revised:2015-12-07 Online:2016-04-01 Published:2015-12-20
  • Contact: SUN Runguang E-mail:runguangsun@aliyun.com
  • Supported by:

    Supported by the Foundamental Research Funds for the Central Universities, China(No.GK201504004).

Abstract:

Interaction between amphotericin B(AmB) and cell membrane is influenced by different metal cations. In the presence of K+, Na+ or Ca2+ ions, the surface pressure-area isotherms and the elastic modulus of an amphotericindipalmitoylphosphatidylcholine(AmB-DPPC) mixed monolayer were discussed. And the excess free energy and entropies of mixing were calculated according to the surface pressure-area isotherms. The phase transition of the mixed monolayer needed a higher concentration of AmB in the sequence Na+ > pure buffer > K+ > Ca2+. When the molar fraction of AmB(xAmB) was 0.5, the molecular interaction changed from attraction to repulsion and the mixed monolayer turned to ordered state from disorder state under the induction of K+ or Ca2+ ions at all surface pressure in our experiment. At high surface pressure, the disorder of monolayer enhanced in the presence of Na+ ions at xAmB > 0.1. At different molar ratios of AmB, the influences of these metal cations were discrepant. These cations may influence AmB molecules to form pores on the monolayer. It is helpful to understand the reduction of AmB's toxicity as theoretical reference.

Key words: Amphotericin B, Phase transition, Metal cation, Molecular interaction