title: Luminescent gold nanoparticles with pH-dependent membrane adsorption.
abstract: pH regulates many cellular processes and is also an indicator of disease progression. Therefore, pH-responsive materials often serve as either tools in the fundamental understanding of cell biology or medicine for disease diagnosis and therapy. While gold nanoparticles have broad biomedical applications, very few of them exhibit pH-dependent interactions with live cells in a native biological environment due to nonspecific serum protein adsorption. Herein, we report that by coating luminescent gold nanoparticles with a natural peptide, glutathione, and the simplest stable aminothiol, cysteamine, we enabled the nanoparticles to exhibit not only high resistance to serum protein adsorption but also pH-dependent adsorption onto live cell membranes in the presence of serum proteins. Incorporating this pH-dependent membrane adsorption behavior into gold nanoparticles could potentially catalyze new biomedical applications of metal nanoparticles in the fundamental understanding of biological processes as well as disease diagnosis and therapy, where pH changes are involved.
authors.affiliation: Department of Chemistry, The University of Texas at Dallas, Richardson, Texas 75080, USA.
authors.forename: Mengxiao
authors.initials: M
authors.lastname: Yu
authors.forename: Chen
authors.initials: C
authors.lastname: Zhou
authors.forename: Jinbin
authors.initials: J
authors.lastname: Liu
authors.forename: Julia D
authors.initials: JD
authors.lastname: Hankins
authors.forename: Jie
authors.initials: J
authors.lastname: Zheng
mesh_terms: D000327:Adsorption; D002462:Cell Membrane / Q000737:chemistry*; D003543:Cysteamine / Q000737:chemistry*; D005978:Glutathione / Q000737:chemistry*; D006046:Gold / Q000737:chemistry*; D006367:HeLa Cells; D006801:Humans; D006863:Hydrogen-Ion Concentration; D049449:Luminescence; D049408:Luminescent Agents / Q000737:chemistry*; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure
chemical_list: D049408:Luminescent Agents; D003543:Cysteamine; D006046:Gold; D005978:Glutathione