<prompt> If you are in PHC, which anticoagulant is used to sent the blood sample for blood glucose estimation? -EDTAHeparinPotassium oxalatePotassium oxalate sodium fluoride  <response>: It is used when blood is collected for glucose estimations. It is a weak anticoagulant but is often added as a preservative for blood glucose together with potassium oxalate as an anticoagulant. It is effective at a concentration of 2mgml blood. It inhibits the enzyme enolase sodium fluoride thus inhibiting glycolysis. Na fluorideK oxalates are mixed in the ratio 1:3. 