ULTRASONIC VELOCITIES, ISENTROPIC COMPRESSIBILITIES AND VISCOSITIES OF BOVINE SERUM-ALBUMIN IN WATER AND WATER CONTAINING ORGANIC-SOLVENTS,SODIUM LAURYL SULFATE AND TETRABUTYLAMMONIUM IODIDE AT 310 K

Ultrasonic velocities (u), densities (rho) and viscosities (eta) of bo vine serum albumin (BSA) have been measured in the protein concentrati on range 0.0022 to 0.0430 g cm(-3) at 310 K in water and water contain ing 11.1 (v/v) % methanol (MeOH), acetonitrile (AN), N,N-dimethylforma mide (DMF) and dimethylsulphoxide (DMSO). Such studies have also been made in water containing 0.042 mol dm(-3) sodium lauryl sulphate (SLS) and 0.033 mol dm(-3) tetrabutylammonium iodide (Bu(4)NI). The isentro pic compressibilities (K-s) of the protein have been estimated in all these systems. Both ultrasonic velocity and isentropic compressibility significantly vary with protein concentration indicating strong struc tural changes (conformational changes) of the protein in ail these sol vent systems. Viscosity results also indicate that BSA undergoes stron g structural changes in the presence of SLS.