Urinalysis Lab
The identification of proteins and sugars in urine samples can reveal kidney disease.
Other characteristics such as color and pH can also help to diagnose kidney disease. This
investigation will involve the use of urine samples to test for indications of disease.
Biuret Reagent can be used to identify proteins. It reacts with the peptide bonds joining
amino acids together, producing color changes from blue, indicating no protein, to pink or
purple indicating more and more protein.
Benedict’s solution can be used to indicate the presence of sugars. In this investigation,
on sample will test positive for sugar and will be indicated by a bright orange colour.
Diagnostic Tool:
Test
Colour
Normal Test Result
Yellow
pH
pH 4.8-7.5
Protein
Glucose
Negative
Negative
Possible Condition/Illness Indicated
Reddish Amber - Urinary Tract Infection
Greenish Yellow - Bile pigments
Smoky Brown - Blood and blood pigments
Low pH (acidic): high-protein diet, diabetes, starvation
High pH (basic): high fiber/vegetarian diet, urinary track
infection
Positive: pregnancy, kidney diseases
Positive: diabetes type 1 or 2
Purpose: To determine which of the samples indicate kidney disease and to diagnose each
sample.
Procedure:
Sugar testing – prepare all samples at once so that you can compare them all at once.
1. Place about 2ml of urine in a test tube
2. Add about 2ml of Benedict’s Solution to the urine sample
3. Place test tube into a hot water bath at 80oC.
4. Observe for about 5 minutes
Protein Testing - prepare all samples at once so that you can compare them all at once.
1. Place 2ml of urine in a test tube
2. Add 2ml of biuret reagent
3. Tap and swirl the test tube to mix.
4. Record the color of each test tube
pH testing – use pH paper to determine the pH of each sample.
Test
Sample
A
Sample
B
Sample
C
Sample
D
Sample
E
Sample
F
Colour
pH (testpaper)
Protein
(Biuret
Reagent)
Glucose
Conclusions:
1.
2.
3.
4.
Which sample could indicate a patient has diabetes insipidus? Provide your reasons.
Which sample could indicate a patient has diabetes mellitus? Provide your reasons.
Which sample could indicate a patient has Bright’s Disease? Provide your reasons.
Which sample could indicate a tremendous loss of body water while exercising? Provide
your reasons.
5. Which sample could indicate a possible kidney stone? Provide your reasons.
6. Which sample could indicate a possible urinary tract infection? Provide your reasons.
Please hand in your diagnosis by ___________________
Teacher Section:
A – Urinary Tract Infection
□ Yeasty smell – add yeast
□ Redish amber colour
□ Low pH acidic 4.8
B – Kidney Stone
□ pH = 6 normal
□ patient complains of pain in lower back
□ smokey brown urine
C- Diabetes Insipidus
□ huge amounts of pee
□ pH = 6 normal
□ very pale b/c lots of pee
□ patient complains of thirst
D- Diabetes Mellitus
□ low pH 4.8
□ glucose (2g in 100ml)
□ pale in colour
E – Loss of water due to exercising
□ dark concentrated pee
□ slightly lower pH = 5.0
□ note that patient complains of thirst
F – Bright’s Disease
□ protein in the urine
□ normal pH = 6
□ patient complains of thirst
□ pee is light because protein will draw in water
Patient A
Patient complains
of hot burning
sensation when
urinating
□
Patient B
Patient complains
of lower back pain
and severe
cramping
□
Patient C
Patient complains
of constant thirst
□
Patient D
Patient often feels
very tired and
lethargic
□
Patient E
Patient is very
thirsty
□
Patient F
Patient complains
of constant thirst
□