Ultrasonic absorption in aqueous solutions of high-molecular-weight polysaccharides.

The ultrasonic amlfiiLudc absorl)liou coelhcient has Iveen determined in aqueous solutions of four molecular weights (73 000, 186 000, 370 000, and 2 {DO 000) of dextran, a linear • (! --• 6) anhydroglucoae polysaccharide of biological origin, over the frequency range 3-69 Mc/sec at 22øC. It is found that the concentrationfree absorption spectrum exhibits a remarkable similarit)' to that of aqueous solutions of beef hemoglobin. The latter finding leads to the conclusion that ultrasonic absorption in tissues is not dominated exclusively by constituent proteins and that the contribution tn such absorption 1W molecular structures lacking tertiary configurations may be considerable.