A biological fluid collection device that is adapted to receive a blood sample having a cellular portion and a plasma portion is disclosed. After collection of the blood sample, the plasma portion is separated from the cellular portion. After separation, the biological fluid collection device is able to transfer the plasma portion of the blood sample to a point-of-care testing device. The biological fluid collection device also provides a closed sampling and transfer system that reduces the exposure of a blood sample and provides fast mixing of a blood sample with a sample stabilizer. The biological fluid collection device is engageable with a biological fluid testing device for closed transfer of a portion of the plasma portion from the biological fluid collection device to the biological fluid testing device. The biological fluid testing device is adapted to receive the plasma portion to analyze the blood sample.
