Urine collection and fluid intake schedule
described
samples
Urine samples should be collected every thirty minutes, as many Analyze each sample as soon as is avoid letting too 1. At the beginning of the lab period, each subject should empty his or her
urinary bladder and note the time
collecting the full
2. After thirty minutes, again empty the bladder, this time sample
This sample will
serve as a pre-treatment contro
iately after step 2, subjects 1-3 should drink the fluid appropriate to
their treatments as quickly as possible. If the sample cannot be finished
before the first sample is taken (below), record the volume
3. that was drunk
empty his or her
4. Thirty minutes after step 2, each subject should again every thirty
bladder, collecting the full sample. Repeat this step twice more, minutes
not be on the thirty-minute mark, be sure to record the exact
If your samples w
time between samples
Measurements
collect data allowing you to determine the rate of
For each urine sample, you wi
of the urine:
urine formation, the concentration of urinary solids, and the pH 1. Volume measurement: Use a graduated cylinder to measure the volume of
each urine sample collected
2. rine pH determination: Check the pH of each urine sample using the
use!
common pH Be sure to rinse the probe with distilled water after 3. Specific gravity measurement: Use a
refractometer to measure the specific gravity of
the urine samples. This device allows
measurement of the concentration of a solution
by the change in angle of light passing through
the sample solutions with a higher specific
gravity refract light to a greater degree
PPT
SG
Open the "door" of the refractometer, place a
1010
1000
drop of urine on the surface, and close the
door
Hold the refractometer to your eye and
determine the reading at which there is a
change in color in the background (see figure)
Rinse the refractometer with distilled water and dry it after each use
4. Chloride concentration: Chloride ion concentration will be measured directly
serve as an indication of salt excretion. Total sodium chloride
concentration will be calculated using a formula provided during lab. The
say is performed spectrophotometrically in a 96-well plate. Each lab group
share one tray to be used for all time points. For each sample: