The influence of molecular structure of protein on the acoustic nonlinearity parameter B/A

I.IntroductionAcousticnonlinearityparameterB/Adescrjbesthenonlilleareffectsofasoundwavetrav-ellingthroughamedium.Withtheapplicationofhighmowerultrasonicwavetomedicine,thenonlineareffectsbecomemoreandmoreimportant.EspeciallybecauseB/Aissensitivetothepathologicalstateofbiologicaltissues1-2])thisprovidesprospectiveapplicationinmedicaldiagnosis.Atpresent,thestudyinthisareaemphasizesontwoaspects.OneistodevelopnewmedicalimagingtechniquesbyusingthisnonlinearityparameterB/Al1'3-'];theotheristostu…

The influence of molecular structure of protein onthe acoustic nonlinearity parameter B/A

In this paper, the influence of molecular structure of proteins on the acoustic non-linearity parameter B/A has been studied. By using biochemical technique, three proteins such as bovine serum albumin, bovine hemoglobin and pepsin were employed and their quarternary,tertiary and secondary protein structures were perturbed by the denaturing agent sodium do-decyl sulfate (SDS) solution, while their primary structures of protein were not changed. This means that only the structural features were altered and the chemical composition maintained unchanged. B/A has been measured by using improved thermodynamic method. The experi-mental results show that when the concentration of SDS solution increases, the alterations of the protein structure increase, and the contribution of protein to the B/A value decreases. Re-sults indicate that the B/A values can display the destruction of molecular structure of protein.Some explanation of these phenomena has also been made in this paper.