Analysis of some Thermodynamic Properties of Bovine Serum Albumin In Aqueous Solution of some Salts at a Fixed Temperature |

ABSTRACT:

Ultrasonicvelocity (u), densities (ρ) and viscosities (η) of aqueous solutions ofammonium dihydrogen phosphate (NH4H2PO4),trisodium citrate, (Na3C6H5O7.2H2O),ammonium sulfate (NH4)2SO4, potassium thiocyanate (KSCN) have beenmeasured in the concentration range between 0.0125 mol dm-3to 0.4 mol dm-3 at 303.15K. Such measurements have been made atconcentration of these salts with fixed concentration i.e 0.02 g cm-3of BSA. The isentropic compressibility (Ks) for various solutionswas calculated by using the equation K, =1/u2P. It has beenfound from the literature survey that a large number of physicochemicalinvestigation of bovine serum albumin (BSA) have been made in water and withother solvent systems under different conditions of pH, temperature, ionic strength and in the presence of varying concentrationof denaturants. The interaction of BSA[1,2], metal ions [3], urea [4,5],sodium dodecyl sulphate [6-9], sulphonamide [10], guanidine hydrochloride[11]and other surfactants, has been investigated. Many physicochemical methodssuch as viscosity [12,13], ultrasonic absorption [4], NMR [9,17-18], ESR [19],dielectric relaxation at microwave frequency [1,20,21], pressure jump [22]arethe method which require special attention. Besides this a little efforts hasbeen made to investigate its nature in mixed solvents especially in water withinorganic metal and transition metal salts. Ultrasonic velocity studies inaqueous solutions of low molecular weight and high molecular weightpolyvinylpyrrolidone have been done by G. Y.Reddy et al. , (1980) Raoformal-Ism has been applied to the polymer solutions and it was observed thatthere was reasonably good correspondence between theoretical and experimentalvalue of Rao's constant. AlastairM.North at a l . . (1981), have reported the adiabatic compressibilitiesof solutions of Polyethyleneoxides(M-400,1000 and 1450) in water, 1- propanol,1 , 2 -ethanediol and 1.2,3-propanetriol at 323K. Ultrasonic absorption and velocity measurements are reportedon aqueous solutions of polyvinylalcohol of differcritmolecular weights,degrees of hydrolysis and concentratl , > n by Abdul Abu-Llakr et al.,(1982). The absorption measurements cover a frequency range from 1-1880MHz and thev elocity data a frequency range from 2-280 MHz, the data were obtained over a temperature range from 273 to 333K. Richard A.Pethrfck et al., (1983) have reported the ultrasonic attenuationand velocity measurements at 2 MHz over a temperature range from 293K to 353for mixtures of Polyethyleneoxide and water for concentrations from 0%to180%.So to understand the nature and strength of interactions in bovine serumalbumin in the case of mixed solvents some solvent properties such as excessthermodynamic functions, viz; excess isentropic compressibility, excess molarvolume, excess enthalpy and excess heat capacity can be well understood bystudying. In the present paper, ultrasonic velocity, densities and viscositymeasurements of BSA have been made in some interesting salt solutions at303.15K to get information on the interactions of this protein.