Analytical Studies on Thrombin in Pure Samples, • Pharmaceutical Preparations and Biological Fluids

Abstract

(ii) In order to select the suitable solvent for CT complex formation, the reaction of DDQ, TCNQ and TCNE with both thrombin is made in different solvents. These solvents include acetonitrile, chloroform, n-propanol, methanol, acetone, tetrahydrofuran, 1,4-dioxane, carbon tetrachloride, n-

1 butanol, 1,2-dichloromethane and dimethyl formamide. The results indicate that acetonitrile is

considered to be an ideal solvent for the colour reaction as it offers solvent capacity a,ild gives the highest yield of the radical as indicated by high E values. This is because it posses es the high dielectric constant of all solvents examined, a property which is known to promote the dissociation of the original CT complex to radical anions i.e. the dissociation of dol)or-acceptor

complex is promoted by the high ionizing power of the solvent.