High-precision THz Dielectric Spectroscopy of Tris-HCl Buffer

  • Lee, Soonsung ;
  • Kang, Hyeona ;
  • Do, Youngwoong ;
  • Lee, Gyuseok ;
  • Kim, Jinwoo ;
  • Han, Haewook
  • Received : 2016.04.29
  • Accepted : 2016.06.01
  • Published : 2016.06.25


Tris-HCl buffer solution is extensively used in biochemistry and molecular biology to maintain a stable pH for biomolecules such as nucleic acids and proteins. Here we report on the high-precision THz dielectric spectroscopy of a 10 mM Tris-HCl buffer. Using a double Debye model, including conductivity of ionic species, we measured the complex dielectric functions of Tris-HCl buffer. The fast relaxation time of water molecules in Tris-HCl buffer is ~20% longer than that in pure water while the slow relaxation time changes little. This means that the reorientation dynamics of Tris-HCl buffer with such a low Tris concentration is quite different from that of pure water.


THz time-domain spectroscopy;Debye relaxation;Tris-HCl buffer


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