ABSTRACT
The number of applications of dextran fractions and derivatives in medicine and medical research has grown considerably over the years. Most of the physical properties of dextran fractions and likewise many pharmacological properties are dependent on the molecular weight distribution of the fraction. Dextrans are readily soluble in water and electrolytes, and very concentrated aqueous solutions of dextran fractions may be prepared. Dextran is also soluble in dimethylsulfoxide, formamide, ethylene glycol, and glycerol but is insoluble in monohydric alcohols. A generalized relationship relating the viscosity of dextran solutions to such parameters as temperature, concentration, and molecular weight has been established. Consideration must be given to the permeability of the individual membranes in vivo since diffusion of small dextran molecules through the membranes will reduce the measured oncotic pressures. The introduction of clinical dextran solutions as plasma volume expanders in 1947 is a prime example of one of the many serendipitous inventions in medicine.
