Mehdi Ramezani is now employed as an Applica- Lukas Sponfeldner is currently working as a post- Shubham Singh wrote his doctoral thesis at the tion Scientist at Chemspeed Technologies. doc at the Department of Physics at the Universi- Biozentrum of the University of Basel. He is ty of Basel. now doing research at the Karolinska Institute in Sweden. Superconducting contacts A combination of good properties Unnatural amino acids For his doctoral thesis, Dr. Mehdi Ra- For his doctoral thesis, Dr. Lukas Spon- for protein screening mezani developed a novel method for feldner manipulated and studied the op- In his doctoral thesis, Dr. Shubham equipping a two-dimensional layer of the tical and electronic properties of two-di- Singh developed and tested a screening semiconductor molybdenum disulfide mensional semiconductors. For part of toolset for incorporating unnatural with superconducting electrical contacts the thesis, he coupled different types of amino acids at specific sites in proteins. for the first time. electron-hole pairs in the van der Waals Fluorescent dyes or other biophysical For future applications in electronics, material molybdenum disulfide. probes can covalently bind to these researchers are studying semiconductors In the two-dimensional material, elec- amino acids, allowing the detailed ex- made of single atomic layers. They can trons leave their place in the “valence amination of proteins. stack such monolayers in order to de- band” due to excitation with light and Proteins are biological nanoma- velop new materials with special proper- enter the “conduction band”. This creates chines that are fundamental to the sur- ties. In part, these are based on complex a positively charged hole, which forms an vival of an organism. Understanding quantum mechanical phenomena that electron-hole pair together with the neg- how they work is therefore of great in- can be put to use in quantum technology. atively charged electron. In two-layer mo- terest for combating diseases or for pro- The method developed by Mehdi Ra- lybdenum disulfide, two different types tein engineering, for example. To study mezani is very helpful when it comes to of electron-hole pairs can form following proteins in detail, researchers transfer better studying these phenomena. excitation with light — depending on the “blueprint” of the proteins (genes) It was important to protect the sensi- whether the hole and electron are in the into mammalian cells and then let them tive atomic semiconductor layer because same layer or adjacent layers. produce the proteins. When this trans- impurities and defects strongly affect the Lukas Sponfeldner has now carried ferred genetic material is modified in a transport of electric charge. In his re- out experiments in which he coupled particular way and the genetic code is search approach, Mehdi Ramezani there- these two types of electron-hole pairs, expanded for the mammalian cells, the fore encapsulated this layer in thin layers combining the beneficial properties of ensuing protein biosynthesis results in of insulating boron nitride. Beforehand, both types. Depending on the purpose, a protein that contains unnatural amino however, he embedded the vertical su- he was therefore able to create fused par- acids at the target sites. perconducting contacts into this protec- ticles that were not only very bright but Shubham Singh has now developed tive layer. In principle, these newly de- also interacted strongly with each other. a cell-based assay to determine the in- veloped vertical contacts to the semicon- This method could also allow researchers corporation efficiency of the unnatural ductor layers could be applied to a variety to produce a novel source of single pho- amino acids via a high-throughput of different semiconductors. tons, which play an important role in screening approach. He has also devel- Publication: https://bit.ly/3WNxW3e quantum communication. In addition, oped and tested a systematic strategy Media release: http://bit.ly/3RRk3Ak the investigation and modelling of cou- for the simultaneous incorporation of Video: https://youtu.be/CsjOtEsh7qA pling are important in order to improve different unnatural amino acids into our understanding of fundamental semi- proteins produced by mammalian cells, conductor physics. thereby providing a tool for studying Publication: https://bit.ly/3HkYrre protein dynamics. Media release: http://bit.ly/3HWTd5b Video: https://youtu.be/Sq_KVBM_WzI 18 SNI Annual Report 2022