Studied on the dynamic adsorption process of Lycium barbarum polysaccharide in the POPC/DPPC monolayers

[Display omitted] •The interaction between LBP and POPC and DPPC was explored by the Langmuir, the Langmuir-Blodgett and AFM techniques.•LBP adsorbed on the POPC or DPPC monolayer by hydrophobic interactions.•The hydrophobic interactions between LBP and POPC were stronger than DPPC.•The different saturation of the chains led to different behavior between LBP and phospholipids. In this study, the interaction between Lycium barbarum polysaccharide (LBP) and unsaturated 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) or saturated 1, 2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) was explored using the Langmuir films technique and atomic force microscopy (AFM). Comparing the pure lipid monolayer with the mixed monolayers, the π-A isotherms of the mixed monolayers shifted to larger molecular areas when LBP was added to the subphase. The compression modulus showed that the compressibility of the monolayer films decreased with the addition of LBP. Adsorption curves revealed that the variation in the surface pressure of LBP with POPC was larger than that with DPPC. This phenomenon was verified by the AFM images and the number of each lipid molecule combining with polysaccharide molecules in the mixed monolayer (Ap value), indicating that hydrophobic interactions between LBP and POPC are stronger than those of DPPC. These findings lay the foundation for exploring the pharmacological mechanism of LBP as an in vivo therapeutic.