The present invention relates to a blood collection unit suitable for accelerated blood coagulation of whole blood for subsequent autologous or allogeneic use. The blood collection unit is characterised in that its inside surface comprises an activation site accelerating coagulation by having a high roughness. Further, the present invention relates to a blood collection unit characterised in that its inside surface comprises an activation site having a high roughness area, and in that the interior of said blood collection unit has been prepared with a pressure of no more than 255 mBar, and preferably a pressure of no more than 130 mBar. Thereby, a blood collection unit rapidly providing coagulated blood products is provided. Said blood products are separated effectively into blood serum and a blood clot absent of additives and contaminants which would make the blood unsuited for certain uses, such as blood testing/analysis, and LeucoPatch®.
