PH of the blood can be estimated potentiometrically using pH meter. Often arterial blood are collected for measuremnet of blood pH.

Sample

Collect arterial whole blood of a patient with 1mg of heparin/ml antiguagulant. This blood yied most eccurate result. But in terms of collecting the sample, if their will be any delay, such that the place where the sample is collected is far from the laboratory any delay at all that will prevent the scientist carry out the test immiidately, the blood sample collected can be store at 2-4digree celcius, the maximum time for storing is 3 hour, the sample sould not be used if the time of storage is obove 3 hours.

Method of arterial blood collection

Often niddle is inserted into the artery before the blood can be colected. the artery sample is often collected are; radial, brachial or femoral artery, but sometime lancent can be use to prick the finger of the patient to collect blood but this time the blood called capilary blood, but finger prick often acomplish with many diadvange, such that finger prick cannot give amount of sample that is required for the test and also it give less accurate result. The reason of using arterial blood instead of venious blood is that arterial blood pressure is much higher than that of venious blood. After the needle is remove from the artery, press firmly on the punchured area for 2 to 5 minute until blood stop coming out from the punture area.