LIST OF TEST UNDER E/U/CREATININE
- ESTIMATION OF SODIUM & POTASSIUM
There are three method used for the estimation of these chemical substance in the serum.
Below are the methods;
- Flame emission spectrometry
- Ion selective electrode (ISE)
- Solid phase or dry reagent technique
But we only focus on flame photometer.
Flame photometer has the following component
Nebulizer: these component help in mixing the sample with air and then spray it to the burner as a fine spray constantly.
Mixing Chamber with Baffles: these components of the photometer help in mixing the atomized and fuel. While the baffles help in separating large particle to waste and allowed the small particle to pass through the flame.
Burner: these component help to reduce metal to atomic state and excite the atom to give out light, with this, it help to control the gas and air pressures, with this control, it help to maintain steady blue flame.
Wavelength Selector: these component help to select wavelength emission that to be measure.
When a light focus the flame this help in selecting a narrow band filter wavelength.
The dilution sample and the standard are carried out manually or by peristaltic pump that is a part of the flame photometry. The diluting substances are made up of lithium. The diluted sample is drowned via capillary tube with the help of the air supply by the compressor.
The air current in the instrument cause splitting of the sample into a haze of tiny droplets, (nebulisation) a larger droplet of the sample go down to the bottom of the nebulising chamber as a waste, while the remaining haze mixed with propane.
The mixture pass through the baffle plate, when passing the air current is ignited which then cause burning and convert the present of metals to atomic forms.
Photo detector measure accurately light wavelength from the flame then the signals from the sodium and potassium are compared from that of lithium at a constant concentration when any change signal is detected as a result of irregularity in the flame, are compare for the same in the lithium channel.
The results are display via digital panel and printed or write out to serve as permanent record.
Flame: gas and air pressure must be regulated carefully so that it will give a constant flame that is blue. The following gas can be used propane,
Nebulizer: make sure the rate of sampling is constant and also the capillary tube must be washing it on every used.
Standard: it is necessary that when carrying out a series of determinations, make sure that standard solution is correctly inserted to give an accurate reading.
In other to avoid the contamination of the standard solution don’t insert a suction probe directly into the storage bottle.
For instrument that have build in diluters, standard solution which have the same viscosity with the plasma or serum should used. But where an internal reference is used, standard, and samples are diluted in a solution containing 15mmol/l litre of lithium nitrate.