Interaction of poly(ethylene glycol)-conjugated phospholipids with supported lipid membranes and their influence on protein adsorption

Abstract

We studied real-time interaction between poly(ethylene glycol)-conjugated phospholipids (PEG-lipids) and a supported lipid membrane by surface plasmon resonance (SPR) spectroscopy to understand dynamic behaviors of PEG-lipids on living cell membranes. Supported lipid membranes formed on a hydrophobic surface were employed as a model of living cell membrane. We prepared three kinds of PEG-lipids that carried alkyl chains of different lengths for SPR measurements and also performed fluorescence recovery after photobleaching (FRAP) to study the influence of acyl chain length on dynamics on the supported membrane. PEG-lipids were uniformly anchored to lipid membranes with high fluidity without clustering. Incorporation and dissociation rates of PEG-lipids into supported membranes strongly depended on the length of acyl chains; longer acyl chains reduced the incorporation rate and the dissociation rate of PEG-lipid. Furthermore, protein adsorption experiment with bovine serum albumin indicated that PEG modification prevented the adsorption of bovine serum albumin on such supported membrane.

Keywords:

• Poly(ethylene glycol)-conjugated phospholipid (PEG-lipids)
• supported lipid membrane
• surface modification
• membrane fluidity
• hydrophobic interaction

Classification:

• 30 Bio-inspired and biomedical materials
• 212 Surface and interfaces

Disclosure statement

No potential conflict of interest was reported by the authors.

Acknowledgements

This work was financially supported by a Grant-in-Aid for Scientific Research on Innovative Areas ‘Nanomedicine Molecular Science’ [number 2306] and by a Grant-in-Aid for Scientific Research (A) [number 21240051], by a Challenging Exploratory Research grant [number 21650118] from the Ministry of Education, Culture, Sports, Science, and Technology of Japan.