Apparatus and method for dispensing phases of blood

Apparatus for dispensing a liquid such as blood, blood sera or blood plasma from a closed blood collection tube comprising:

• (a) closure piercing means having an end shaped for piercing a stopper of a blood collection tube and for extending into the tube;
• (b) liquid path means located within said closure piercing means for defining an opening through the stopper when the closure piercing means is inserted through the stopper of the blood collection tube;
• (c) gas passage means to allow gas to be introduced into the interior of the blood collection tube for the purpose of dispensing liquid from the tube, gas passage means having flow restriction means to substantially prevent liquid from entering said gas passage;
• (d) sealing means for preventing gas from escaping between the stopper of the blood collection tube and the apparatus;
• (e) a sensing means to determine the amount of liquid contained within the blood collection tube and to produce a first signal indicative of that amount;
• (f) input means to produce a second signal indicative of a specified quantity of liquid to be dispensed;
• and
• (g) controlling means responsive to first and second signals to regulate the introduction of gas into the blood collection tube so that the specified quantity of liquid is dispensed.