what is the composition of platelet counting fluid ?

Answer 1

Through automated technology, the RBC count, Hb, Hct, and platelet count are available in about 30 sec. In rare cases, blood counts can also be measured by mixing a measured volume of blood with an appropriate diluent or lysing agent and counting in a chamber under the microscope. Hb can be measured colorimetrically after treatment with dilute hydrochloric acid, which permits colorimetric or spectrophotometric comparison with standards of hematin or cyanmethemoglobin, respectively. Hct can be measured by centrifuging a volume of blood and determining the percentage of RBCs relative to total blood volume. The WBC differential count is measured by staining a drop of blood on a glass slide with a metachromatic stain (eg, Wright's) and examining it with oil immersion microscopy. A minimum of 100 WBCs are counted; each type is reported as a percentage. Some automated instruments also measure differential counts by pattern recognition. The platelet number can be estimated on the blood
smear (using 20,000/µL for each platelet seen in a given [90×] oil immersion field).

Answer 2

There are several fluids used to count platelets. I'm assuming you mean performing a manual platelet count in a lab, using the fluid and a microscope. It is a diluent consisting of ammonium oxalate, Sorensen's buffer and Thimerosal in water (there are other diluents used).
This is used to make a dilution of blood. The red cells are haemolysed, leaving the white cells and platelets slightly stained and visible. The dilution is placed in a counting chamber (hemacytometer)and allowed to settle for about ten minutes, and the cells are then counted, using the dilution to calculate the platelet count in the blood.
Is this what you were after?

Answer 3

eh - what exactly is your question?
The fluid you count platelets in is blood...which consists of cells suspended in liquid. This suspension is separated by spinning it in a centrifuge which results in 3 layers - the top being plasma, the buffy coat where the white blood cells and platelets are and the red blood cells which form a sort of cake at the bottom.
has a very complicated composition of blood cells, platelets, water, amino acids, hormoned, lipids, electrolytes etc..
there are a couple of different ways for platelet counting, the most common are by impedance or by manually counting them.

Answer 4

would you believe i actually forgot the ingredients? as a licensed medtech, I should've known that.. except we're using the automated machines these days.. sigh.. the advent of these techno wonders made me dull really.. why don't you check out bernard henry's clinical laboratory's sort of manual for every medtech subject.. there's a section there on hematology.. you can easily find the topic on plt counting and the components of the counting fluid.. although, i think labsci really knows what he's talking about.. i remember the sorensen buffer as part of it. ;)