silica-based columns and polymer-based columns.
silica gel provides better resolution because the pore size distribution is
sharper and the pore volume is larger than polymer-based columns. However,
as silica gel with large pore size cannot be used for GFC analysis because of it
brittleness, polymer-based column is suitable for the separation of macromolecules.
In general, silica-based columns are recommended for protein separations of low molecular weight
from a few thousand to approximately one million. And polymer-based columns would be best
used for the analysis of proteins, lipoproteins or DNA with molecular weights of more than
one million. OHpak SB-800 HQ series
packed with polyhydroxymethacrylate gel allows the analysis
of proteins of low molecular weight range of less than 10,000, for which silica-based columns
would show low resolution.
Silica-based columns cannot be used with the eluent whose
pH is 7.5 or more because silica gel is dissolved in such eluent. In contrast, polymer-based
columns have a wider usable eluent pH range and these columns can be washed with alkaline
solution, resulting in longer column life. The usable pH range for OHpak SB-800 HQ series
is from 3 to 10, whereas the usable pH range for Asahipak GF-HQ series is form 2 to 9.
The packing material of Asahipak GF-HQ or
series is a highly cross-linked polyvinyl alcohol gel.
Their packing material delays the elution of substances such as human and bovine serum albumins which
show strong affinity with the molecular structure of the packing material due to interaction with the
molecular structure of the packing material. Making use of this characteristics, Asahipak
is especially used for the analysis of serum albumin.