A Study on Ratio of Loss to Storage Modulus for the Blood Clot

In this study, the rheology of blood clot is measured with the help of rotational rheometer.Several shear strains (0.5, 1 and 2%) are applied with two frequencies (5 and 10 Hz) from theincipient time of clot formation and the response of the sample is measured in the form of shearstress and the phase lag which is interpreted with storage and loss moduli. In this study the ratioof loss to storage modulus is studied and the blood clot gel-point as the transition fromviscoelastic fluid to viscoelastic solid is investigated. By increasing the frequency, tan delta decreases before the gel-point and increases after the gel-point which indicates the viscoelasticfluid and viscoelastic solid behaviour,respectively. Moreover, by increasing the shear strain, tandelta varies with lower rate at luidic stage (Ra1 and Ra3) and with higher rate at solid stage(Ra2 and Ra4). It is also shown that increasing the shear strain causes a delay on gel-pointformation