title: Tuning the interactions of PEG-coated gold nanorods with BSA and model proteins through insertion of amino or carboxylate groups.
abstract: Gold nanorods (GNRs) are important platforms for biosensing and drug delivery. As for most nanomaterials, appropriate coatings such as polyethylene glycol (PEG) are needed to stabilize GNRs within biological fluids. We show here that the interactions of GNRs with proteins can be finely modulated through surface modification using PEG-containing chains bearing charged headgroups. Interestingly, introduction of amino or carboxylate groups produces relevant and differential changes in GNR interactions with three representative proteins: lysozyme, cytochrome c, and bovine serum albumin. These effects were explored through the direct monitoring of plasmonic bands of the GNRs and are supported by independent dynamic light scattering (DLS) and circular dichroism (CD) determinations. Notably, GNR-protein interactions observed for these charged GNRs can be almost completely reversed by salt addition. These observations demonstrate the importance of electrostatic effects in governing GNR-protein interactions, and provide a basis for new sensing and delivery platforms.
authors.affiliation: Department of Chemistry "Ugo Schiff", University of Florence, Via della Lastruccia 3-13, Sesto Fiorentino, 50019, Florence, Italy; Department of Chemistry, University of Massachusetts, 710 North Pleasant Street, Amherst, MA 01003, USA. Electronic address: federica.scaletti@unifi.it.
authors.forename: Federica
authors.initials: F
authors.lastname: Scaletti
authors.affiliation: Department of Chemistry "Ugo Schiff", University of Florence, Via della Lastruccia 3-13, Sesto Fiorentino, 50019, Florence, Italy.
authors.forename: Alessandro
authors.initials: A
authors.lastname: Feis
authors.affiliation: Institute of Applied Physics "Nello Carrara", National Research Council, Via Madonna del Piano 10, Sesto Fiorentino, 50019, Florence, Italy.
authors.forename: Sonia
authors.initials: S
authors.lastname: Centi
authors.affiliation: Institute of Applied Physics "Nello Carrara", National Research Council, Via Madonna del Piano 10, Sesto Fiorentino, 50019, Florence, Italy.
authors.forename: Roberto
authors.initials: R
authors.lastname: Pini
authors.affiliation: Department of Chemistry, University of Massachusetts, 710 North Pleasant Street, Amherst, MA 01003, USA.
authors.forename: Vincent M
authors.initials: VM
authors.lastname: Rotello
authors.affiliation: Department of Chemistry "Ugo Schiff", University of Florence, Via della Lastruccia 3-13, Sesto Fiorentino, 50019, Florence, Italy.
authors.forename: Luigi
authors.initials: L
authors.lastname: Messori
mesh_terms: D000818:Animals; D002087:Butyrates / Q000737:chemistry; D002417:Cattle; D002645:Chickens; D002942:Circular Dichroism; D045304:Cytochromes c / Q000737:chemistry*; D000067493:Dynamic Light Scattering; D005021:Ethylamines / Q000737:chemistry; D006046:Gold / Q000737:chemistry*; D006736:Horses; D009113:Muramidase / Q000737:chemistry*; D043942:Nanotubes / Q000737:chemistry*; D009994:Osmolar Concentration; D011092:Polyethylene Glycols / Q000737:chemistry*; D011485:Protein Binding; D012710:Serum Albumin, Bovine / Q000737:chemistry*; D013055:Spectrophotometry, Infrared
chemical_list: D002087:Butyrates; D005021:Ethylamines; D012710:Serum Albumin, Bovine; D011092:Polyethylene Glycols; D006046:Gold; D045304:Cytochromes c; C421864:hen egg lysozyme; D009113:Muramidase
keywords: Electrostatic interaction; Gold nanorods; Plasmonics; Protein interaction; Protein sensing