Question

How much amount of capillary blood is required by a micro-electrode for determination of pH?

(a) 5 to 10 ml

(b) 10 to 12 ml

(c) 12 to 18 ml

(d) 20 to 25 ml

Answer 1

The correct option is (d) 20 to 25 ml

Explanation: A micro-electrode for clinical applications requires only 20–25 ml of capillary blood for the determination of pH. The electrode is enclosed in a water jacket with circulating water at a constant temperature of 38°C. The water contains 1% NACI for shielding against static interference.