Liquid part of blood (6)
I believe the answer is:
plasma
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">liquid part of blood</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for plasma that I've seen before include "State" , "part of donor's contribution?" , "Colourless fluid of the blood and lymph" , "Component of TV screen" , "Clear fluid portion of blood" .)