Hi Partha,

Interesting observation.  This could be as a result of action of the platelets.  Once you put the blood in the serum tube, due to contact activation the coagulation cascade is initiated with the FXII getting converted into FXIIa and subsequent fibrin or clot formation.  When you centrifuge the clotted blood you get the serum as a supernatant.  However if the blood platelets are activated or if the blood donor had hyperresponsive platelets and if you put the blood in the serum tube and eventually after clotting, you centrifuge the blood you may see that gelatinization of the serum.  This is my opinion.

Omer Iqbal

sir. 

The content looks like jelly. Ans same type of thing was observed on second day collection also... even though it is clear we cant pipette the clear part out. And if we tilt the tube it doesnt move.

There is increased coagulation activation and also platelet activation especially in animal blood.  So by the time you collect the blood and put into a tube there is already too much platelet activation and this may result 'gelatinization of the serum.  Blood draw should not be slow to activate the blood.  Blood draw should be smooth and relatively fast.

Thank you sir,

regarding the collection of blood i can tell it was done nicely as only 2 samples got gelatinised but others were straw coloured. and on repeatation also only those twogot gelatinised again .

Dear sir

The speed to separate serum is about 1500 rpm for 15 min. Is there any problm if we will di so at higher speed like 4000 

The coagulation process leads to formation of fibrin, and that is probably what you see as a gel.

Thank you sir

But peculiarity is that only few tubes only got the problrm and that re-occured on repeatation. Only 2 animals in a herd showed the same 

What kind of animals are you collecting blood from? How long do  you store the blood before centrifugation? How do you collect the blood? Are tubes without additives? What is the g-force of your centrfuge?

The g-force is very important for the separation of blood and the sedimentation of cells and fibrin. The g-force depends on the rpm and the radius of the centrifuge. 1500 rpm may be sufficient if the radius is long.

Fibrin formation may take some time, in particular if you collect the blood in plastic tubes. Storage for one hour at room temperature before centrifugation ensures that the clot formation is completed before centrifugation.

Species GOAT

AGE 2 YR

2000 RPM FOR 20 MIN

 STERILISED NEW PLASTIC CONTAINORS 

STORED FOR ALMOST 2 HR

This is really informative. Sir one more thing. Is there any impact of storage of blood sampless before separating serum. Sometimes people keep theor samples for even 4 h before centrifugation and tell that it will facilitate clot formation. Is there any time limit minimum and maximam stogare before centrifugation.

Regards

Partha

Partha - coagulation is slow in plastic containers. Can you collect the blood in sterilised glass tubes, or transfer the blood to such tubes and store forr at least one hour before centrifugation?

If you collect in plastic tubes you can add glass beads or thrombin and CaCl2 to your blood after collection. This will speed up the clotting process.

Whar is the serum used for?

Best regards

Johannes

Wat may be the maximam time before centrifugation for serum?

Biochemica parametrs are of  our interest

The storage time will depend on the temperature and the biochemical parametres to be analysed. Two hours are OK in most cases.

For hormone and enzyme analysis which sample is better .  Plasma or serum. Please justify.

Most hormone analyses can be performed in serum. Phosphatases and other enzymes can also be measured in serum. Coagulation enzymes, on the other hand, should be measured in citrate-stabilized plasma.

Thank you sir. 

But there was some gelly like separation while separating blood serum. i feel same wont be there in plasma. so better to go for plasma samples as biochemical paramters are least affected. what is your opinion sir?

Regards

Partha

Hi Partha

Plasma can be used for many hormones and enzymes. EDTA-stabilized plasma is preferable, as the blood remains undiluted, and EDTA binds calcium much stronger than citrate. Again, however, keep in notice that citrate-stabilized plasma should be used for coagulation enzymes. The enclosed file may be helpful.

If the problems with fibrin (gelly layer) persist in serum samples you may transfer the serum to another tube and centrifuge again. I presume that this will solve the problem.

Best regards

Johannes

dear sir,

after taking all kinds of precautions and also after using glass vacutainer tubes also i am getting the same gelatin formation during collection of serum. Do u have any recent feed backs and possible reasons in this measure.?

is this due to any special disease in goats?

regards

partha

Dear Partha

Fibrin is the end product of the coagulation process and it is completely normal that fibrin is observed in the specimen, when you collect serum samples. I enclose a review of the coagulation system for your information.

I can be difficult to spin the fibrin down. Some precautions may help.

- Let the blood clot for more than 30 minutes before centrifugation to allow the coagulation to complete.

- If fibrin gel is oberserved you can use a small wooden stick or a pipette to loosen it from the inside of the tube and then spin the sample again

Using a special tube containing a gel that separates the fibrin clot from the serum will solve the problem. The tubes are sold by Becton Dickinson and other companies.

https://en.wikipedia.org/wiki/Serum-separating_tube

Best regards

Johannes

Thank you dr johannes

This is also a fact that i have always given a span of aroind 2-3 hr for clump formation. And in gelatin when i want to separate the possible liquid part some thread lile structure also appears. When i aliquot to a new tube again it behave lile a jelly.

This may be attributed to the the faulty clotting procedure but this condition appears only in 2 specific animals out of 24.

Regards

Partha