Doctors can discover a lot about someone from their urine, including kidney disease, dietary
habits, diabetes, and drug abuse.
The Scene
A jewelry store in Abington was looted, and the burglar foolishly used the potty before leaving
the store (the employees don’t use it because they know it doesn’t flush). The villain’s urine
and samples from 4 suspects has been collected.
Your team will perform tests on all 4 samples and the burglar’s sample to find a match, AND
also to determine if information from the urine tests corresponds to evidence about the
suspects.
There are four tests to do on each samples of urine: examination by eye for color, protein
testing, pH testing and glucose testing. Your tests are done by placing drops of urine in a well
plate, combining the drop with the appropriate test indicator, and noting any change.
Examination by eye for color
Label 4 columns on a well plate with the names of the suspects, and a 5 th column “Villian”.
Place 2 drops of a sample in 4 different wells for each column. Examine the urine samples
carefully by eye and comment on the color of the urine. Try to use words like yellow, amber,
dark, clear and pale. Note your observations in your Piddle Chart.
Test for protein
To test for protein put 2 drops of Biuret reagent into one well for each sample. Stir each well
with a separate stirring stick. If the solution turns from blue to purple, protein is present in the
urine (not a good thing). Record your observations on the piddle chart
pH testing
Now you need to find out the pH of the urine samples. Dip a piece of universal indicator paper
into the urine. Quickly take it out, and leave it for 30 seconds. Compare the new color with the
pH color chart, and note the pH number on your Piddle Chart.
Testing for glucose
The last test is to find out if the urine contains glucose, (also not usually a good thing). Dip a
glucose test strip into the urine sample, and immediately take it out. Count to ten, then check
the color with the color chart. Record whether the urine is negative, light, medium or dark
(dark means a lot of glucose).
Emily
Mario
Luke
Sarah
Villain
Color
Protein?
pH
Glucose?
Use the following information and your notes from our previous class to answer
the case questions as a group.
Urine Color and Possible Causes
Color
Diet
Light yellow
normal
Clear
alcohol
Amber to orange
carrots
red
beets
Brown
Rhubarb
Drugs
Disease
steroids
antibiotics
diabetes
Gall bladder
problems
Blood in urine
Laxatives or
barbiturates
(downers)
antidepressants
Urine Analysis Results and Possible Causes
Test result
Diet
Low pH (<5)
High Protein, many
juices, alcohol
High pH (>8)
Rich in Vegetables, dairy
Glucose present
Following Very large
meal
Protein Present
Regular high protein
Liver malfunction
Disease
Diabetes
Anemia (low iron)
Diabetes
Anemia
Tinkle Test Group Names:
Emily
Mario
Luke
Sarah
Villain
Color
Protein?
pH
Glucose?
Who do you think was the likely suspect?
Explain your reasons (pee analysis and alibi)
What further evidence could you gather from a location other then the jewelry
store that would confirm the suspect’s guilt (assume the jewels are hidden
away)?
Some of the original suspects have been cleared by the urine analysis, but their
urine shows possibly serious medical conditions. Identify 2 suspects with
abnormal urine and describe what might be wrong with them.