Effects of surface functionalization on the adsorption of human serum albumin onto nanoparticles – a fluorescence correlation spectroscopy study

• Pauline Maffre,
• Stefan Brandholt,
• Karin Nienhaus,
• Li Shang,
• Wolfgang J. Parak and
• G. Ulrich Nienhaus

Beilstein J. Nanotechnol. 2014, 5, 2036–2047, doi:10.3762/bjnano.5.212

• replaced by less prevalent proteins having a higher binding affinity (Vroman effect [16]). Thus, given that the rate coefficients governing protein binding and unbinding are of suitable magnitude, one may observe an initial, short-lived “soft corona” that subsequently develops into a long-lived “hard

• measure the binding of various proteins. In the present study, we focus on a single protein, again HSA, and explore the change in protein binding onto CdSe/ZnS core–shell QDs with different surface functionalities. These NPs were water-solubilized with small thiolated ligands, leading to thin coatings

• QDs with various small ligands, polymer-coated QDs and Fe–Pt NPs as well as DHLA-coated gold and silver nanoclusters (NCs) [49]. Affinity measurements on the latter NPs were performed by measuring their luminescence enhancement due to protein binding rather than by using FCS. For native HSA, the

In vitro and in vivo interactions of selected nanoparticles with rodent serum proteins and their consequences in biokinetics

• Wolfgang G. Kreyling,
• Stefanie Fertsch-Gapp,
• Martin Schäffler,
• Blair D. Johnston,
• Nadine Haberl,
• Christian Pfeiffer,
• Jörg Diendorf,
• Carsten Schleh,
• Stephanie Hirn,
• Manuela Semmler-Behnke,
• Matthias Epple and
• Wolfgang J. Parak

Beilstein J. Nanotechnol. 2014, 5, 1699–1711, doi:10.3762/bjnano.5.180

• responses in tissues and cells cannot be neglected a priori but require thorough investigations. Therefore, we studied the interactions and protein binding kinetics of blood serum proteins with a number of engineered NP as a function of their physicochemical properties. Here we show by in vitro incubation

• subsequent accumulation in secondary organs and tissues but also the the transport across organ membranes depended on the route of AuNP application. Our in vitro protein binding studies support the notion that the observed differences in in vivo biokinetics are mediated by the NP protein corona and its

• dynamical change during AuNP translocation in fluids and across membranes within the organism. Keywords: biokinetics; gold nanoparticles; protein corona; protein–nanoparticle conjugate; serum protein binding; surface modification; Introduction Like any foreign material that enters into the organism

The protein corona protects against size- and dose-dependent toxicity of amorphous silica nanoparticles

• Dominic Docter,
• Christoph Bantz,
• Dana Westmeier,
• Hajo J. Galla,
• Qiangbin Wang,
• James C. Kirkpatrick,
• Peter Nielsen,
• Michael Maskos and
• Roland H. Stauber

Beilstein J. Nanotechnol. 2014, 5, 1380–1392, doi:10.3762/bjnano.5.151

• the properties of the NP dictate the extent and specificity of protein binding profiles, which are complex, and in line with other studies may well consist of more than hundred different proteins [22][27][28][29]. Albeit we did not perform a detailed identification of the protein corona composition by

Mapping mechanical properties of organic thin films by force-modulation microscopy in aqueous media

• Jianming Zhang,
• Zehra Parlak,
• Carleen M. Bowers,
• Terrence Oas and
• Stefan Zauscher

Beilstein J. Nanotechnol. 2012, 3, 464–474, doi:10.3762/bjnano.3.53

• thermal evaporator (Kurt Lesker PVD 75), and subsequently cleaned by ozone plasma ashing (Emitech K-1050X). Protein monolayer Five tandem B-domains of staphylococcal protein A were expressed and purified from E. coli. The C-terminus of the terminal protein was modified with cysteine to enable protein

• binding to the gold surface. Protein patterns were prepared by dry stamping of the tandem B-domains on to the gold substrate surface, by using a polyurethane (pUA) stamp (15 µm hexagon). The pUA stamp was UV cross-linked on a silicon master with hexagonal pattern features and, before each use, cleaned by

Characterization of protein adsorption onto FePt nanoparticles using dual-focus fluorescence correlation spectroscopy

• Pauline Maffre,
• Karin Nienhaus,
• Faheem Amin,
• Wolfgang J. Parak and
• G. Ulrich Nienhaus

Beilstein J. Nanotechnol. 2011, 2, 374–383, doi:10.3762/bjnano.2.43

• = 0.1 ms (for ease of comparison). Evidently, the curves shift toward longer times with increasing protein concentration, indicating that the effective size of the NPs grows due to protein adsorption. The effect is small, however, so precise data are needed for a quantitative analysis of protein binding

• diameter of a single α-helix separated by 2 nm, we obtain an overall thickness of 5–6 nm for the protein corona, which closely matches the observed ΔRH (Figure 2c, Table 1). About 65 apoE4 molecules will attach to the NP upon complete formation of the protein corona (Table 1). Protein binding affinity The