Patent ID: 7341873

Claim:
A method of determining the quality of a sample of platelets using dynamic light scattering, the method comprising: a. obtaining a sample of platelets (I); b. collecting dynamic light scatter from the sample of platelets; c. calculating an average hydrodynamic radius of the platelets in the sample based on the dynamic light scatter; d. measuring a temperature response of the platelets in the sample, said temperature response comprising: i. varying the temperature of the sample, by cooling the sample to cause platelet activation; ii. repeating the steps (b)-(c) above, wherein a temperature response is detected as a change in average hydrodynamic radius in the platelet sample resulting from varying the sample temperature; e. comparing the average hydrodynamic radius and the temperature response to the values obtained from a fresh platelet sample (II); and, f. concluding that the platelet sample (I) is out-dated wherein: i. the average hydrodynamic radius of the platelet sample (I) is less than 75% of the average hydrodynamic radius of a fresh platelet sample (II); and ii. the temperature response of the platelet sample (I) is less responsive relative to the temperature response of the fresh sample (II).