While dispatching blood and urine for chemical analysis, sodium fluoride is added as preservative in the following concentration -: (A) 30 mg/10 ml, (B) 40 mg/10 ml, (C) 50 mg/ ml, (D) 100 mg/10 ml
Answer is D. 10 mg/ml of Na-fluride (i.e. 100 mg/10 ml) is used with 3 mg of potassium oxalate for preserving blood.