Unfolding of Poly-L-glutamic Acid by Microbubbling of Supercritical Carbon Dioxide

Abstract

  The conformational changes in α-helical poly-L-glutamic acid caused by microbubbling supercritical CO₂ were investigated with circular dichroism spectra. After microbubbling using a micropore filter at 35 and 30 MPa for 30 min, α-helix content decreased to 37%, while without the filter it was 68%. The α-helix structure was significantly decomposed by a high density of CO₂. No important changes were observed in heating, autoclaving, or pH-lowering.