Open Positions

PhD and postdoctoral researcher level
For further information in PhD and post-doctoral studies in the Meier group, please contact Prof. Wolfgang Meier (wolfgang.meier@unibas.ch)

Undergraduate Projects and Master thesis level 
We currently have projects to offer in the areas of Nanoscience, Macromolecular Chemistry, Polymer Chemistry, Physical Chemistry and similar. If you are interested in a position for an Undergraduate Project (Wahlpraktikum, Projektarbeit) or for a Master of Science contact Prof. Wolfgang Meier (wolfgang.meier@unibas.ch) or Prof. Cornelia Palivan (cornelia.palivan@unibas.ch).

Master projects are described below:
   
 
   
Project 1:

Cascade reactions within polymersome clusters: from model to application
Compartimentalization is a fundamental aspect of biology. To study how the distance between compartments influences the communication and the reaction efficiency, we need to control the distance between them and polymersomes. By conjugating complementary DNA strands on them, polymersomes form binary clusters with inter-vesicle distance tuneable by simply varying the length of the DNA bridge.  In addition, the DNA also interacts with the membrane proteins mammalian cells, opening the possibility to selectively act upon the membrane-exterior interface.

This project will consist of two main phases: in the first phase, the enzymatic cascade mediated by superoxide dismutase (SOD) and lactoperoxidase (LPO), detoxifying both the dangerous ROS superoxide and hydrogen peroxide, will be characterized at different DNA lengths and we will derive a model of the dependence cluster diffusion of the reaction efficiency. In the second phase, we will study the interaction of these catalytically active clusters with different cell lines and verify their ability to help the cells survive oxidative stress, a major cause of cell damage.

Several different physicochemical techniques will be used to study the nanoscale assemblies composed of polymers, enzymes and DNA, coupled to the biochemical analysis of enzymatic activity and basic toxicology studies on cell cultures, making this a largely interdisciplinary project that will provide with a broad overview on nanobiotechnology research.

If interested please contact Andrea Belluati (andrea.belluati@unibas.ch) with your CV and a tentative starting date. 

References
[1] Tanner, P., et al., Enzymatic cascade reactions inside polymeric nanocontainers: a means to combat oxidative stress. Chemistry, 2011. 17(16): p. 4552-60.
[2 Liu, J., et al., DNA-Mediated Self-Organization of Polymeric Nanocompartments Leads to Interconnected Artificial Organelles Nano letters, 2016. 16(11): p. 7128–7136.
[3] Palivan, C.G., et al., Protein-polymer nanoreactors for medical applications. Chem Soc Rev, 2012. 41(7): p. 2800-23.

    

Project 2:

Analyzing molecular parameters for efficient nuclear targeting by polymer-hybrid nanocarriers
The cell nucleus is the ultimate target for many therapeutic treatments including cancer, brain disorders or heart dysfunctions. Here, the usage of nanocarrier systems is highly advantage in order to deliver degradation sensitive agents directly to the targeted site and to reach sufficient concentrations of the active therapeutic form in situ. The engineering of nanocarriers however, is a delicate task and requires careful design and throughout optimization of the carrier scaffold [1]. On this account, we have developed functional polymer-hybrid nanocarriers that are selectively uptaken into the cell nucleus (see figure). The nuclear import is thereby directed by multiple copies of covalently surface on-bound nuclear localization sequences (NLSs). These short peptide sequences are recognized by soluble transport receptors (known as karyopherins or importins) and mediate the translocation of the assembled complex in vivo [2]. In fact, nanocarrier complexes are traversing the nuclear envelope in order to reach the nucleus via  ̴ 80 nm in diameter spanning nuclear pore complexes (NPCs) [3]. In which manner however, the structural and nanomechanical carrier properties are effecting the nuclear uptake viability still remains unclear. The goal of the project is therefore to fabricate nanocarriers with diverse physicochemical properties and to evaluate optimal molecular parameters for efficient nuclear import.

Importantly, this master project is a collaborative work between the Lim (Biozentrum, Unibas) and the Palivan (Physical Chemistry Department, Unibas) lab and as such, it is established on the technical and experimental capabilities of both the research groups. To apply for the project, please send an email with your CV and a tentative starting date to Christina Zelmer (christina.zelmer@unibas.ch).

References
[1] S.N. Tammam, H.M.E. Azzazy, A. Lamprecht: “How successful is nuclear targeting by nanocarriers?“, J. Control. Release 229, 140-153, (2016).
[2] M. Stewart: “Molecular mechanism of the nuclear protein import cycle“, Nat Rev Mol Cell Biol 8, 195-208, (2007).
[3] A. Hoelz, E.W. Debler, G. Blobel: “The Structure of the Nuclear Pore Complex“, Ann Rev Biochem 80, 613-643 (2011).
Additional literature
[4] C.G. Palivan, R. Goers, W. Meier: “Bioinspired Polymer Vesicles and Membranes for Biological and Medical Applications”, Chem. Soc. Rev 45, 377-411 (2015).
[5] S. Vujica, C. Zelmer, R.Y.H. Lim: `Nucleocytoplasmic Transport: A Paradigm for Molecular Logistics in Artificial Systems`, CHIMIA 6, 413-417, (2016).
    
Project 3:

Functional Degradable vesicles and micelles from radical ring-opening polymerisation
The query for new biomimetic polymers is one of the major driving forces in life sciences and also in polymer chemistry. With respect to polymer-based life-science research, multi-responsive and biodegradable polymers are required and will be created in this project. The current mix of polymeric materials consists in large portions of polyvinylic polymers from radical polymerisation or polyesters and polyamides from ring-opening polymerisation. These materials have the disadvantage that they are either responsive or biodegradable – the combination is rarely reported but is required for any biomedical application and also beyond. It is the aim of this project to fill this gap, allowing for novel multi-responsive and biodegradable polyesters and polyamides. The tool to achieve these polymers is controlled radical ring opening polymerisation (CoRROP). [1] This chemistry only shows a small number of published studies, but can have a great potential. A major advantage of CoRROP is that it can combine the benefits of radical polymerisation (e.g. being robust and allowing for functional units) with ring opening polymerisation (e.g. biodegradable materials). Polymers from CoRROP will be useful in a variety of fields: Degradable responsive hydrogels for smart drug delivery of drugs, polymer brushes as temporary protective coatings which respond on an external trigger and also smart and degradable polymer self-assemblies. The latter will be the focus of this project.
This project will start with the synthesis of the monomers, cyclic ketene acetals and continue to polymerise them to amphiphilic block-copolymers. Once available, the material will be applied in self-assembly studies to investigate which self-assembly structure is formed and how well the polymer degrades. Students on this project will thus cover basic organic chemistry, polymer chemistry [2-3] and applied polymer science (self-assembly) including a broad variety of techniques from all these fields.
Please contact Dr. Jens Gaitzsch (jens.gaitzsch@unibas.ch)

[1] S. Agarwal, Polym. Chem., 2010, 1, 953-964.
[2] W. J. Bailey, Z. Ni and S. R. Wu, J. Polym. Sci., Part A: Polym. Chem., 1982, 20, 3021-3030.
[3] U. M. Battisti, C. Sorbi, S. Franchini, A. Tait and L. Brasili, Synthesis, 2014, 46, 943-946


L
ast update: June 2018