Accessible Unlicensed Requires Authentication Published by De Gruyter March 7, 2018

Germanium Plasmon Enhanced Resonators for Label-Free Terahertz Protein Sensing

Maximilian Bettenhausen, Friedhard Römer, Bernd Witzigmann, Julia Flesch, Rainer Kurre, Sergej Korneev, Jacob Piehler, Changjiang You, Marcin Kazmierczak, Subhajit Guha, Giovanni Capellini and Thomas Schröder
From the journal Frequenz


A Terahertz protein sensing concept based on subwavelength Ge resonators is presented. Ge bowtie resonators, compatible with CMOS fabrication technology, have been designed and characterized with a resonance frequency of 0.5 THz and calculated local intensity enhancement of 10.000. Selective biofunctionalization of Ge resonators on Si wafer was achieved in one step using lipoic acid-HaloTag ligand (LA-HTL) for biofunctionalization and passivation. The results lay the foundation for future investigation of protein tertiary structure and the dynamics of protein hydration shell in response to protein conformation changes.

Funding statement: Funder Name: Deutsche Forschungsgemeinschaft, Funder Id: 10.13039/501100001659, Grant Number: ESSENCE Program


The work presented has been funded in part by the German Research Foundation (DFG) within the project ESSENCE (Electromagnetic Sensors for the Life Sciences).


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Received: 2018-1-5
Published Online: 2018-3-7
Published in Print: 2018-3-26

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