title: Using a selective cadmium-binding peplipid to create responsive liquid crystalline nanomaterials.
abstract: A specific metal ion-responsive lipid liquid crystalline (LLC) dispersion system was fabricated, which can work in buffer solutions. The LLC matrix was prepared from phytantriol which spontaneously forms the reversed bicontinuous cubic phase in water, and a novel peptide-lipid conjugate (peplipid) consists of a myristate alkyl chain for anchoring into the phytantriol-based cubic bilayer and a peptide sequence for capturing a specific metal ion. The peplipid in its unbound state, when added into the phytantriol-based cubic system induces a positive effect on the bilayer curvature, resulting in the formation of the lamellar phase (vesicles) and the dispersion was transparent in appearance. Upon binding of the cadmium ion, the peplipid induces a negative effect on the lipid bilayer curvature and consequently leading to the formation of cubic phase and opaque appearance. In contrast, other metal ions, including buffering salts, could not sufficiently trigger the phase transition due to weak interaction with the peplipid. The high selectivity of metal ion interaction and triggered phase transition provide potential applications, such as in colloidal-mineral separation, triggered drug release and treatment of cadmium (II) pollution.
authors.affiliation: Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University (Parkville Campus), 381 Royal Parade, Parkville, VIC 3052, Australia; ARC Centre of Excellence in Convergent Bio-Nano Science and Technology, Monash Institute of Pharmaceutical Sciences, Monash University (Parkville Campus), 381 Royal Parade, Parkville, VIC 3052, Australia.
authors.forename: Qingtao
authors.initials: Q
authors.lastname: Liu
authors.affiliation: Australian Future Fibres Research and Innovation Centre, Institute for Frontier Materials, Deakin University, Geelong, VIC 3217, Australia.
authors.forename: Jinfeng
authors.initials: J
authors.lastname: Wang
authors.affiliation: Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University (Parkville Campus), 381 Royal Parade, Parkville, VIC 3052, Australia.
authors.forename: Yao-Da
authors.initials: YD
authors.lastname: Dong
authors.affiliation: Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University (Parkville Campus), 381 Royal Parade, Parkville, VIC 3052, Australia; ARC Centre of Excellence in Convergent Bio-Nano Science and Technology, Monash Institute of Pharmaceutical Sciences, Monash University (Parkville Campus), 381 Royal Parade, Parkville, VIC 3052, Australia. Electronic address: ben.boyd@monash.edu.
authors.forename: Ben J
authors.initials: BJ
authors.lastname: Boyd
mesh_terms: D002104:Cadmium / Q000032:analysis*; D005233:Fatty Alcohols / Q000737:chemistry*; D050866:Liquid Crystals / Q000737:chemistry*; D008958:Models, Molecular; D019814:Myristic Acid / Q000737:chemistry*; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure; D010455:Peptides / Q000737:chemistry*; D044367:Phase Transition; D053838:Scattering, Small Angle; D014961:X-Ray Diffraction
chemical_list: D005233:Fatty Alcohols; D010455:Peptides; D002104:Cadmium; D019814:Myristic Acid; C508873:3,7,11,15-tetramethyl-1,2,3-hexadecanetriol
keywords: Lipid liquid crystalline; Metal ion; Nanoparticle; Peptide; Phase transition; Specificity