Nanostructure and biomolecule interactions: Characterizing the complex

Research output: ThesisDoctoral Thesis (compilation)


This thesis presents the results of studies done on various biomolecules and their interactions with nanomaterials. The biomolecule sources are everything from purified, single proteins to the complicated mixture of blood serum and cell culture media. Similarly, the nanomaterial sources vary from spherical titanium dioxide, gold, and polystyrene nanoparticles to novel nanowires of gallium arsenide or gallium phosphide. Regardless of the biomolecules or nanomaterials, they interact in ways that require careful characterization in case the environment and organisms are exposed to theses increasingly common materials. The adsorbed protein layer on a nanostructure is called the protein corona and the nanomaterial together with its adsorbed biomolecules is called a complex.
We show that when titanium dioxide nanoparticles are mixed with blood serum, a broad range of complex sizes are formed.
Traditionally, the protein corona has been considered homogeneous for specific nanoparticle and serum concentration ratio.
However, our results show that the corona varies with the complexes’ size.
We also look at the effect protein has on very low concentration of 20 nm gold nanoparticles in cell culture medium. Using a
combination of analytical techniques, we show that in protein enriched cell culture medium, the nanoparticles are stable. In cell
culture medium without added protein, the nanoparticles aggregate slowly. We describe the aggregation rate and the aggregate
morphology and identify arginine, an aggregation inducing amino acid in the biomolecular corona.
Furthermore, we study the binding of purified proteins on nanowires by cryo-transmission electron microscopy, X-ray based
analytical techniques, and by changes in the sedimentation rate of nanowires with and without adsorbed protein layer. By rotating
the electron microscope stage during imaging, we can image irregularities in the protein corona formed by the large, cross shaped protein laminin.
Finally, we study the effect of various nanostructures on the activity of the enzyme myeloperoxidase. The nanostructures’ effect
was highly dependent on the complexity of the environment. The effect ranged from almost total inactivation to increasing the
activity up to three-fold.


  • Stefan Gunnarsson
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Biochemistry and Molecular Biology


  • Nanostructures, Proteins, Lipids, Protein corona, Aggregation, Sedimentation, Diffusion, Electron microscopy, Enzyme activity, Nanowires, Nanoparticles
Original languageEnglish
Awarding Institution
Supervisors/Assistant supervisor
Award date2018 Oct 10
Place of PublicationLund
  • Lund University
Print ISBNs978-91-7422-592-1
Electronic ISBNs978-91-7422-601-0
Publication statusPublished - 2018 Sep
Publication categoryResearch

Bibliographic note

Defence details Date: 2018-10-10 Time: 10:00 Place: Kemicentrum Lecture Hall B, Naturvetarvägen 14, Lund External reviewer(s) Name: Höök, Fredrik Title: Professor Affiliation: Biological Physics, Department of Physics, Chalmers University of Technology, Sweden ---

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Related research output

Sanfins, E., Correia, A., Gunnarsson, S. B., Vilanova, M. & Tommy Cedervall, 2018 Jan 1, In : PLoS ONE. 13, 1, e0191445.

Research output: Contribution to journalArticle

Gunnarsson, S. B., Katja Bernfur, Anders Mikkelsen & Tommy Cedervall, 2018, In : Nanoscale. 10, 9, p. 4246-4257 12 p.

Research output: Contribution to journalArticle

Martin Hjort, Bauer, M., Gunnarsson, S., Mårsell, E., Zakharov, A., Karlsson, G., Sanfins, E., Christelle Prinz, Reine Wallenberg, Tommy Cedervall & Anders Mikkelsen, 2016, In : Nanoscale. 8, 7, p. 3936-3943

Research output: Contribution to journalArticle

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