Week 7 Lab: Urine Chemical Analysis Flashcards
intermediate products of fat metabolism
Ketone bodies
Ketone bodies include?
- acetone
- acetoacetic acid
- beta-hydroxybutyric acid
Measurable amounts of ketones do not appear in the urine because of the complete metabolism of fats into?
carbon dioxide and water
Ketone bodies appear in the urine when there is an increase in?
fat metabolism
Ketone bodies can be seen in the following conditions?
- inability to metabolize carbohydrates, as occurs in Diabetes mellitus
- increased loss of carbohydrate from vomiting
- inadequate intake of carbohydrates associated with starvation and weight reduction
Ketone bodies can be detected in?
urine
What reaction is employed in the analysis of ketone bodies?
Nitroprusside reaction
In Nitroprusside reaction, acetoacetic acid in an alkaline medium will react with sodium nitroprusside to produce?
a purple color
In Nitroprusside reaction, __________ in an alkaline medium will react with _________ to produce a purple color.
acetoacetic acid, sodium nitroprusside
Nitroprusside reaction does not measure?
beta-hydroxybutyric acid
Nitroprusside reaction is only slightly sensitive to?
acetone
The different tests employing Nitroprusside reaction are?
- reagent strip
- acetest
- Legal’s test
- Rothera’s test
Acetoacetic acid is also determined using?
Gerhardt’s test
Gerhardt’s test combines acetoacetic acid with ferric chloride to produce a?
red color
Gerhardt’s test combines __________ with __________ to produce a red color.
acetoacetic acid, ferric chloride
It is performed to detect beta-hydroxybutyric acid.
Hart’s test
In Hart’s Test, the beta-hydroxybutyric acid remained after the removal of acetone and acetoacetic acid by boiling is made to react with?
hydrogen peroxide
Materials used in tests for the determination of Acetone/Acetoacetic Acid that serves as positive control?
acetone
Tests for the determination of Acetone/Acetoacetic Acid?
- Rothera’s Test
- Legal’s Test
- Acetest
Procedure for Rothera’s Test?
- Saturate one(1) gm of ammonium sulfate in five(5) cc. of fresh urine
- Add 2 drops of sodium nitroprusside and mix thoroughly
- Overlay with sodium hydroxide and note the development of a purple color at the zone of contact in the presence of diacetic acid or acetone. If the color does not appear immediately stand for 10 to 15 minutes before reporting as negative
Procedure for Legal’s Test?
- To 3 ml of urine in a test tube, add NaOH or KOH solution just enough to make the urine alkaline
- Add few drops of concentrated acetic acid.
- Add few drops of sodium nitroprusside solution.
- Observe for the solution to turn red to purple in the presence of acetone or acetoacetic acid.
Procedure for Acetest?
- Place Acetest reagent tablet on a small piece of paper of white surface
- Put a drop of urine on tablet.
- Compare the color tablet with the color chart after 30 seconds Tablet turns purple in the presence of acetone or diacetic acid
Diacetic acid: Trace or (+1)
10-20 mg%
Diacetic acid: Moderate or (+2)
25-40 mg%
Diacetic acid: Strong or (+3)
over 50 mg%
Acetone: Trace or (+1)
25-50 mg%
Acetone: Moderate or (+2)
200-250 mg%
Acetone: Strong or (+3)
400-1000 mg%
Tests for the determination of Diacetic Acid (Acetoacetic Acid)?
- Gerhardt’s Test
- Lindemann’s Test
Procedure for Gerhardt’s Test (Preliminary)?
To 5 cc. of urine, add 10% FeCl, until all phosphates are precipitated. Filter if necessary
and add more ferric chloride. A bordeaux red color indicates the presence of diacetic acid, aspirin, salicylates, phenol, antipyrine and sodium bicarbonate.
Procedure for Gerhardt’s Test (Confirmatory Test)
a. To 5 ce of another fresh portion of the urine specimen, add an equal volume of water and a drop of conc HNO, and boil down to the original volume (5 cc). This will convert all the diacetic to acetone which will volatilize
b. Cool and add 10% FeCl
Note: If negative for bordeaux red color, it is positive for the presence of diacetic acid
Procedure for Lindemann’s Test?
- To 5 cc of urine, add 2 drops of 20% acetic acid, 3 drops of Iodine solution and 2-3 drops of chloroform
- Shake gently. The chloroform layer will not change if diacetic acid is present and will become reddish violet if absent.