TY  - JOUR
AU  - Ruks, Tatjana
AU  - Loza, Kateryna
AU  - Heggen, Marc
AU  - Prymak, Oleg
AU  - Sehnem, Andre Luiz
AU  - Oliveira, Cristiano L. P.
AU  - Bayer, Peter
AU  - Beuck, Christine
AU  - Epple, Matthias
TI  - Peptide-Conjugated Ultrasmall Gold Nanoparticles (2 nm) for Selective Protein Targeting
JO  - ACS applied bio materials
VL  - 4
IS  - 1
SN  - 2576-6422
CY  - Washington, DC
PB  - ACS Publications
M1  - FZJ-2021-01676
SP  - 945 - 965
PY  - 2021
AB  - Ultrasmall gold nanoparticles with a metallic core diameter of 2 nm were surface-conjugated with peptides that selectively target epitopes on the surface of the WW domain of the model protein hPin1 (hPin1-WW). The binding to the gold surface was accomplished via the thiol group of a terminal cysteine. The particles were analyzed by NMR spectroscopy, high-resolution transmission electron microscopy, and differential centrifugal sedimentation. The surface loading was determined by conjugating a FAM-labeled peptide, followed by UV–vis spectroscopy, and by quantitative 1H NMR spectroscopy, showing about 150 peptide molecules conjugated to each nanoparticle. The interaction between the peptide-decorated nanoparticles with hPin1-WW was probed by 1H–15N-HSQC NMR titration, fluorescence polarization spectroscopy (FP), and isothermal titration calorimetry (ITC). The particles showed a similar binding (KD = 10–20 μM) compared to the dissolved peptides (KD = 10–30 μM). Small-angle X-ray scattering (SAXS) showed that the particles were well dispersed and did not agglomerate after the addition of hPin1-WW (no cross-linking by the protein). Each nanoparticle was able to bind about 20 hPin1-WW protein molecules. An unspecific interaction with hPin1 was excluded by the attachment of a nonbinding peptide to the nanoparticle surface. The uptake by cells was studied by confocal laser scanning microscopy. The peptide-functionalized nanoparticles penetrated the cell membrane and were located in the cytosol. In contrast, the dissolved peptide did not cross the cell membrane. Peptide-functionalized nanoparticles are promising agents to target proteins inside cells.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000643599900072
DO  - DOI:10.1021/acsabm.0c01424
UR  - https://juser.fz-juelich.de/record/891697
ER  -