How can we help?

You can also find more resources in our Help Center.

64 terms

Clinical Chemistry Final Lab Practical

STUDY
PLAY
Glucose Oxidase
D-Glucose + H2O + O2 ------------------------------- H2O2 + D-Gluconate

POD
H2O2 + 4-AAP + Hydroxybenzoate---->Quinoneimine dye + H2O
Principle for Glucose Oxidase (equation)
Glucose Oxidase Principle
Glucose is oxidized by glucose oxidase to gluconate and hydrogen peroxide.
Phenol + 4-AAP + hydrogen peroxide, in the presence of peroxidase,
produces a quinoneimine dye that is measured at 500nm. The absorbance
at 500nm is proportional to the concentration of glucose in the sample.
What is Glucose Oxidase Linear to?
500mg/dl
Albumin Principle
Albumin is bound by the BCG dye to procedure an increase in the blue-green color measured at 630 nm. The color increase is proportional to the concentration of albumin present.
What is Albumin linear to?
0.5 - 8.0 g/dl
Alkali
Alkali Protein + Cu++----------␣Colored Complex (protein conc.)
Total Protein (Biuret) Reagent Set Equation
Total Protein (Biuret) Principle
Protein in serum forms a violet colored complex when reacted with cupric ions in an alkaline solution. The intensity of the violet color is proportional to the amount of protein present when compared to a solution with known protein concentration.
Alkaline phosphatase principle
p-Nitrophenol phosphate is hydrolyzed to p-nitrophenol and inorganic phosphate. The rate at which the p-NPP is hydrolyzed, measured t 405 nm, is directly proportional to the alkaline phosphatase activity
What is Total Protein (Biuret) linear to?
1.0 - 15 g/dl
What is alkaline phosphatase linear to?
800 IU/L
After reconstitution of reagents how long are they stable for?
...
Diagnosis: Glucose Oxidase Increase/Decrease
Blood sugar levels outside the normal range may be an indicator of a medical condition. A persistently high level is referred to as hyperglycemia; low levels are referred to as hypoglycemia. Diabetes mellitus is characterized by persistent hyperglycemia from any of several causes, and is the most prominent disease related to failure of blood sugar regulation.
Glucose Oxidase Normal Ranges
The normal range for Adults is 64.8 and 104.4 mg/dL. For children from birth to age 5, normal blood sugar targets are 100 to 200mg/dL. For children who are between the ages of 5 and 11, normal blood sugar targets are 70 to 150mg/dL.
Where is Glucose oxidase synthesized in the body?
...
Which reagent set is used for the qualitative determination of glucose in serum?
Glucose Oxidase
What pipette do you use to rehydrate controls?
Volumetric pipet
What formula is used to calculate abs?
(Absorbance unknown sample /Concentration of Standard Absorbance) x concentration of standard =
Clinical Significance: Uric acid crystals are seen in normal urine. They may also be associated with kidney stone formation.
Clinical significance: Calcium oxalate crystals may be seen in normal urine. Calcium oxalate is the major component of kidney stones in adults
Increases with high vegetable intake

Hippuric Acid
Clinical Significance: Calcium phosphate crystals are seen in normal urine. They may also be associated with kidney stone formation
Clinical Significance: Triple phosphate crystals are seen in normal urine. They may also be associated with kidney stone formation.
Clinical Significance: Calcium carbonate crystals can be seen in normal urine.
Clinical Significance: Ammonium biruate crystals can be seen in normal urine. However, the presence of ammonium biurate crystals usually indicates an old or poorly preserved specimen
Squamous epithelial cell

Ammmonium biurates
Clinical Significance: Bilirubin crystals are seen in several hepatic disorders.

Bilirubin Crystals
Calcium phosphate
Clinical significance: Cholesterol crystals are usually associated with Nephrotic Syndrome.
Cholesterol
Clinical significance: Cystine crystals are found in the inherited condition, cystinuria. Cystine crystals are the most frequent cause of kidney stones in children.
Clinical significance: Leucine crystals may be seen in liver disorders in which amino acid metabolism is impaired.
Clinical significance: Tyrosine crystals may be seen in tyrosinemia and in certain liver disorders in which amino acid metabolism is impaired.
Tyrosine Crystals
Clinical Significance: Sulfonamide crystals may appear in the urine following antibiotic therapy with sulfonamides. They may be associated with kidney stone formation.

Sulfonmide crystal
Sulfonamide crystals
Clinical significance: WBC casts are associated with inflammation or infection within the kidney.

white cells present
How to determine color/tubidity
The presence of RBCs in urine is clinically significant. They may be associated with disease, injury, or infection of any portion of the renal system.
Clinical Significance: Trichomonas is a common cause of vaginitis and is usually indicative of a STD.


Squamous epithelial cell
Clinical significance: Yeast is a common cause of urinary tract infection in immunocompromised or diabetic patients
yeast*
Clinical Significance: Waxy casts usually indicate end stage renal disease

Waxy cast*
Clinical Significance: RBC casts are the most diagnostic of all elements in urinary sediment. Their presence is always pathological. RBC casts are primarily indicative of an acute disorder of the glomerulus
Clinical significance: WBC casts are associated with inflammation or infection within the kidney. The presence of WBC casts is an indication that the WBC seen in the sediment are originating in the kidney
Clinical significance: Granular casts are occasionally seen in urine from normal individuals after strenuous exercise or stress. Increased numbers of granular casts may be seen in a variety of kidney diseases but are not indicative of any specific renal disorder.

Granular cast*
Sperm
Clinical Significance: Hyaline casts may be seen transiently following fever, stress, exercise or postural changes in normal individuals. Increased numbers of hyaline casts may be seen in all diseases of the kidney but are not indicative of any specific renal disorder.
Squamous epithelial cell*
Hyaline cast*
Clinical Significance: Oval fat bodies are frequently associated with nephrotic syndrome.
oval fat bodies
The presence of RBCs in urine is clinically significant. They may be associated with disease, injury, or infection of any portion of the renal system
grading (microscopic urine)
What is the proper storage of the reagent strips?
*protect from moisture/chemicals/heat and light
*keep lid tight and do not discard dessicant
*store below 30C (85F)
Ictotest
confirmatory test for bilirubin
place tablet on mat and add water
Diazo reaction=Bilirubin reacts w diazonium salt to produce tan, pink, violet
Clinitest
ability of glucose to reduce copper sulfate to cuprous oxide in presence of heat and alkali
Acetest
Test for ketones-uses sodium nitroprusside and lactose (tablet test)
SSA
more sensitive to globulin
-test for protein add equal amounts sample to ssa in test tube.
what can produce false reactions on reagent strip?
old urine, contaminated reagents.....ect.
What method of choice is recommended when x ray contrast dyes have been administered?
...
After reconstitution how long are reagents stable for?
...
How to handle hemolyzed, lipemic or icteric samples?
Use a sample blnk
Where are chemicals synthesized in the body?
...
Reagent blank
contains all the reagents that are necessary for the reaction except the constituent to be measured.
Sample/ Serum blank
is useful when a serum is colored by a substance that are not being measured and do not interfere chemically with the reaction. ex)hemolyzed, lipemic or icteric samples
Describes the closeness of the test value to the true value
Accuracy
Usually refers to the reproducibility of a test value
Precision
continuous movement in one direction; caused by reagent or instrument. (6 continuous results that are increasing or decreasing.
Trend
Movement all above or below the Mean (x6 total results)
Shift