 Measurement Principle: The PocketChem BA measures blood ammonia based on the micro-diffusion method. When the blood sample 20 microlitre is applied to the sample-receiving layer of the test area on the test strip, the alkaline buffer agent borate buffer impregnated in the layer dissolves making the specimen alkaline. The ammonium ions in the specimen are gasified by the alkaline state into ammonia gas. The ammonia gas passes through the pores of the spacer to the indicator bromocresol green triggering color development. As the degree of color development is proportional to the concentration of ammonia gas produced, the blood ammonia level is quantitatively determined by measuring the color. 