Modulation of membrane properties by silver nanoparticles probed by curcumin embedded in 1,2-Dimyristoyl-sn-glycero-3-phosphocholine liposomes

Abstract

Development of nanomaterials has drawn interest on silver nanoparticles (AgNPs), which are being incorporated in several biomedical and environmental applications, especially anti-bacterial properties of AgNPs has intense excitement for their commercial use. However, the impact of AgNPs on cell membranes, such as phospholipid membrane properties, is not clearly understood yet. By applying curcumin as a probe molecule, this work was done for the first time to investigate the effect of AgNPs on membrane properties, such as permeability and phase transition temperature using 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) liposomes as a model for phospholipid membranes. We concluded that AgNPs at low concentration decrease the partition of curcumin into DMPC liposomes by ∼4-fold. In the presence of AgNPs, curcumin was found to be located close to the stern layer of DMPC liposomes by using a hydrophobic quencher, cetylpyridinium bromide (CPB). In addition, AgNPs broadened the phase transition temperature of DMPC liposomes, which ranged from 20 °C to 35 °C.