Critical flocculation concentrations, binding isotherms, and ligand exchange properties of peptide-modified gold nanoparticles studied by UV-visible, fluorescence, and time-correlated single photon counting spectroscopies.
Protocols for modifying gold nanoparticles with peptide-bovine serum albumin (BSA) conjugates are described within. The resulting constructs were characterized using a number of techniques including static fluorescence spectroscopy and time-correlated single photon counting spectroscopy (TCSPC) in order to quantify peptide-BSA binding isotherms, exchange rates, critical flocculation concentrations, and the composition of mixed peptide-BSA monolayers on gold nanoparticles. TCSPC has proven to be a powerful technique for observing the microenvironment of protein-gold nanoparticle conjugates because it can distinguish between surface-bound and solution-phase species without the need for separation steps. Full characterization of the composition and stability of peptide-modified metal nanoparticles is an important step in their use as intracellular delivery vectors and imaging agents.
Xie
Huan
H
Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695, USA.
Tkachenko
Alexander G
AG
Glomm
Wilhelm R
WR
Ryan
Joseph A
JA
Brennaman
Matthew K
MK
Papanikolas
John M
JM
Franzen
Stefan
S
Feldheim
Daniel L
DL
D015082:2,2'-Dipyridyl / Q000031:analogs & derivatives* / Q000737:chemistry; D000595:Amino Acid Sequence; D000818:Animals; D001667:Binding, Competitive; D002417:Cattle; D056831:Coordination Complexes; D004228:Dithionitrobenzoic Acid / Q000737:chemistry; D005427:Flocculation; D005450:Fluorescamine / Q000737:chemistry; D005978:Glutathione / Q000737:chemistry; D017979:Gold Colloid / Q000737:chemistry* / Q000378:metabolism; D007700:Kinetics; D008024:Ligands; D036103:Nanotechnology / Q000379:methods*; D010316:Particle Size; D010455:Peptides / Q000737:chemistry*; D011485:Protein Binding; D012235:Rhodamines / Q000737:chemistry; D012710:Serum Albumin, Bovine / Q000737:chemistry / Q000378:metabolism; D013050:Spectrometry, Fluorescence; D013053:Spectrophotometry; D013056:Spectrophotometry, Ultraviolet; D013388:Succinimides / Q000737:chemistry; D013438:Sulfhydryl Compounds / Q000737:chemistry; D017975:Ruthenium Compounds
D015082:2,2'-Dipyridyl; D056831:Coordination Complexes; D004228:Dithionitrobenzoic Acid; D005450:Fluorescamine; D005978:Glutathione; D017979:Gold Colloid; D008024:Ligands; D010455:Peptides; D012235:Rhodamines; D012710:Serum Albumin, Bovine; D013388:Succinimides; D013438:Sulfhydryl Compounds; C547232:tris(2,2-bipyridine)-ruthenium(II); D017975:Ruthenium Compounds; C013097:3-maleimidobenzoyl N-hydroxysuccinimide; C027755:rhodamine isothiocyanate