Agarose films were prepared using a variety of casting conditions, hea
t treatments, and solvation treatments. Films represented the high tem
perature sol, the room temperature gel, and a high temperature state w
ith cross-links intact. The vacuum uv CD of the film samples varies co
nsiderably, but the similarities between the film CD and the previousl
y reported solution CD show that dehydration per se does not affect th
e CD. Combining the CD results for the dried sol with the x-ray result
s of Foord and Atkins leads to a description of the high temperature s
ol in terms of locally extended chain conformations. The CD of the gel
and its peculiarly high uv absorption are satisfactorily, albeit not
uniquely, interpreted in terms of the double-helix model of the gel, i
n agreement with previous conformational studies based on chiroptical
properties. (C) 1994 John Wiley and Sons, Inc.