Specimen Flashcards
Whole blood (complete blood) with anticoagulant added is obtained from these three sources.
Vein, Arteries, and Skin
Liquid portion of uncoagulated blood
plasma
Most common blood specimen in Clinical Chemistry
Serum contained in a red top (plain) tube
Factors of GITT that is affected by eating.
Elevated: Glucose, triglycerides
Decreased: Inorganic Phosphates
Appearance: Thymol turbidity
This specimen contains viral microorganisms that invade deeper organs.
Cerebrospinal Fluid (CSF)
Effects of exercise include:
Immediate Effect:
glucose undergoes glycolysis (Glucose to Pyruvate)
Delayed Effect: enzymes elevate
- Aspartate Transferase(AST) or Serum glutamic oxalate transanunirase(SGOT)
- Alanine Transferase(ALT) or Serum glutamate pyruvate transanunirase (SGPT)
- Creatinine Kinase (CK)
- LD (Lactate Dehydrogenase)
Long-term Effect
Increased hormones
What is the reason for the removal of proteins in samples colleted?
- Hinders color reaction
- Produces ppt. mask w/ a true color end product
- Produces bubbles, interferes colorimetry reading
* Ex: spectrophotometry = 0 absorbance (due to gas)
Methods of PFF (4)
Folin-Wu Method (Precipitation of protein by the addition of H2WO4 (Tungstic acid) used in FBS
Nelson Somogyi (Removal by protein sedimention by addition of 0.3 N of ZnOH2 and 5% ZnSO4) used in FBG
Haden Method (Same as Folin-Wu but with pre-mixed reagent)
Van Slyke Method (Proteins are ppt. by addition of 10% TCA, centrifugation and decantation) used for ppt. of inorg phosphorus
Steps of the clotting process. (3)
- Generation of thromboplastin - Produced by thrombocytes (platelets) which areCa+2dependent
- Conversion of prothrombin to thrombin by thromboplastin
- Conversion of fibrinogen to fibrin clot by thrombin
Oxalate
o 0.01 mL 30% citrate sol. / mL of blood
o Black top
o Ppt.Ca+2 to CaC2O4
o Not used in clinical chemistry
EDTA
o 1-2 mg / ml of blood
o Purple top
o Chelating agent, chelates Ca+2 complex
o Commercially: K-EDTA
o For HbA1Canalysis
* Glycosylated hemoglobin present in diabetic patients
* Monitors diabetes mellitus
o Not used for K+ determination in blood, as EDTA can falsely elevate K+ level in the patient’s serum
Citrate
o Orange top
o Ppt. calcium
o For donor blood
o Not used in clinical chemistry
Sodium Flouride
o 10 mg / mL of blood
o Gray top
o Best for glucose determination
* Preserve glucose for 24-28 hours
o Prevents glycolysis by inactivating enolase
o Inactivates urease enzyme
o Instead of NaF, iodoacetate is present
* Inactivates glyceraldehyde-3-phosphate dehydrogenase
Heparin
o 0.1-0.2 mg / mL
o Green top
o Naturally occurring
* Manufactured by liver
* Present in blood stream
o An antithrombin (AT) and antiprothrombin (AP)
o Best for pH measurement, pO2 (partial oxygen tension), and pCO2 (partial carbon dioxide tension)
Yellow top
o Blood culture
o Additive: sodium polyanethol sulfunate
