Open positions

  • PhD Position in Natural white pigments based on Guanine

    The Adolphe Merkle Institute's Soft Matter Physics Group (Prof. Ullrich Steiner) and the Soft Matter and Photonics Group (Prof. Frank Scheffold) at the Physics Department of the University of Fribourg invite applications for a PhD Position in Natural white pigments based on Guanine.

    Many industries today use nanoscale white pigments, including food, pharma, inks, paint, and coatings. The white pigment market is dominated by one material: titanium dioxide (TiO2). Recently regulators in Switzerland and the EU have moved to ban the material, however, deeming it unfit for consumption as a food additive (E171). In parallel, companies are turning to natural and sustainable solutions, seeing them as strategic opportunities because of customer demand for these products.

    Inspired by marine animals and spiders, this research project aims to manufacture, optimize and characterize high refractive index optical scatterers, or nanoscale particles, from guanine. Guanine is the biopolymer with the highest known refractive index (n=1.83) and is therefore ideally suited to maximize the dielectric contrast between the scatterers and their surrounding medium. To assure industrial feasibility, the project will be accompanied by Dr. Raphaël Pugin (CSEM). The project will be part of the National Center of Competence in Research Bio-Inspired Materials network (, whose technology transfer manager will train the student with technology transfer skills and assist the project in commercialization.

    Applicants must have a Master’s degree in Chemistry or Polymer/Materials Science and wish to pursue interdisciplinary research in a fast-moving international team. Experience in polymer synthesis and processing, the ability to advance a complex project independently and as part of a team, excellent communication skills, and proficiency in English are key requirements for this position. Previous experience in the synthesis of biopolymers and optics is desirable. AMI offers attractive employment conditions and outstanding infrastructure in a new research facility.

    The position will be filled as soon as possible. Please send your CV, motivation letter, and contact information of at least two references as one PDF file via E‐mail to with the subject title “PhD Position Guanine”.