Superlubricity by glycerosome boundary layers

The search for high-performance lubricants is of broad relevance to biomedical applications, including artificial joints, regenerative scaffolds, and osteoarthritis therapies. Here we introduce glycerosomes-phosphatidylcholine (PC)-based vesicles containing glycerol-as a promising boundary lubricant. Using a surface force balance, we show that glycerosomes achieve a friction coefficient as low as 10^-5 under a high compression pressure of 15.6 MPa, representing a 20-fold reduction compared to conventional PC liposomes. This level of lubrication surpasses any previously reported boundary lubricant system at such pressures in aqueous media. Mechanistically, glycerosomes exhibit substantially lower adhesion energy than PC liposomes, and theoretical simulations reveal enhanced vesicle stability and flexibility. Our findings establish glycerosomes as a superior hydration lubrication platform, with promising implications for both biomedical implants and industrial applications requiring robust lubricity.