Conclusion: The number of platelets collected did not differ significantly from the 2 pool groups 5 and 6 buffy-coat bags, the number of residual leukocytes was below the permitted limit, the pH value was within the range of 6.4 - 7.4, no abnormalities in the platelet bags when implanted. So, the storage time of buffy coat platelets for 7 days still ensures the quality according to domestic and foreign regulations.