NUTR 442 – Nutrition Assessment Laboratory
Assessment of Protein and Iron Status
Assessment of Protein Status
1. Mid-arm muscle circumference
Data:
Subject Name
Subject age
Subject gender
Mid-arm muscle
circumference
(mm)
Tricep skinfold
thickness (mm)
Determine the following:
1.
2.
Arm muscle area - standard procedure (p-228, upper equation)
Arm muscle area - "bone free" – (p-228, lower equation; modified by
Heymsfield
Percentile AMA - APPENDIX Q; p 553 - using #2
3.
2. Serum Albumin
Procedure (Work in groups of three)
1.
2.
3.
4.
Pipet 1000 ul of Albumin Reagent (bromcresol green) into 6 tubes (2
tubes per person)
Pipet 10 ul of your plasma into each of two tubes. Dispose tip.
Repeat with other serum samples.
Cover tube with parafilm and gently invert 3X
Pour into semi-micro cuvette and measure absorbance @ 628nm
within 1 minute of addition.
Data:
Subject Name
Abs @ 628 nm of
tube 1
Abs @ 628 nm of
tube 2
Concentration of albumin standard = ____________ g/dl
Absorption @ 628 of albumin standard = ____________ _____________
Determine the following for each subject:
[ subject serum albumin (g/dl) ] = Abs @ 628 nm of serum_________
Abs @ 628 nm of albumin standard
x
[ albumin standard]
Assessment of Iron Status
3. Hematocrit
Procedure:
1.
2.
3.
4.
5.
6.
Lance your finger and obtain a nice size drop of blood (twice the size
of a pinhead)
Fill a small hematocrit capillary tube
Push one end into the hematocrit clay to plug that end
Put capillary tube into the hematocrit rotor. Place a balancing capillary
tube opposite your tube (unless there is another student ready to spin
their tube; in this case be sure you know the position number of your
capillary tube)
Press the HCT button on the centrifuge to start the centrifuge spinning
After the centrifuge has stopped spinning and the lid opens, take out
the hematocrit capillary tube and measure the packed red blood cell
height and total blood height on the hematocrit gauge.
Data:
Name of subject
Hematocrit (%)
Total serum iron determination.
Procedure: (Work in groups of three)
1.
2.
3.
4.
5.
6.
Pipet 1000 ul of Iron Buffer Reagent into six tubes.
Pipet 200 ul of your serum into each of two tubes. Dispose tip.
Repeat with other serum samples.
Add 20 ul of iron color reagent to all tubes.
Mix contents of tube covered with Parafilm by gently inverting 3X..
Incubate tubes at 37 degrees C. for 10 minutes
Pour contents into cuvette, place into spectrophotometer, record
absorption at 560nm
Data:
Subject Name
Abs @ 560 nm of
tube 1
Abs @ 560 nm of
tube 2
Concentration of iron standard = ____________ ug/dl
Absorption @ 560 nm of iron standard = ____________ _____________
Determine the following for each subject:
[ subject serum iron (ug/dl) ] = Abs @ 560 nm of serum_________
Abs @ 560 nm of iron standard
x
[iron standard]
Unsaturated Iron-Binding Capacity (UIBC) Determination
Procedure: (Work in groups of three)
1.
2.
3.
4.
5.
6.
7.
Pipet 1000 ul of UIBC Buffer Reagent into six tubes.
Pipet 250 ul of your serum into each of two tubes. Dispose tip.
Repeat with other serum samples.
Pipet 250 ul of Iron Standard into each tube.
Mix contents of tube covered with Parafilm by gently inverting 3X..
Add 25 ul of iron color reagent to all tubes.
Mix contents of tube covered with Parafilm by gently inverting 3X..
Incubate tubes at 37 degrees C. for 10 minutes
8.
Pour contents into cuvette, place into spectrophotometer, record
absorption at 560nm
Data:
Subject Name
Abs @ 560 nm of
tube 1
Abs @ 560 nm of
tube 2
Concentration of iron standard = ____________ ug/dl
Absorption @ 560 nm of iron standard = ____________ _____________
Determine the following for each subject:
UIBC (ug/dl) = [iron std] - Abs @ 560 nm of serum_________
x
[iron standard]
Abs @ 560 nm of UIBC iron standard
Calculate Total Iron Binding Capacity (TIBC) (ug/dl)
TIBC = UIBC + [serum iron]
Calculate % Iron Saturation (%)
% iron saturation = ( [serum iron] / TIBC ) x 100
Expected Values
Serum Iron = 60 – 150 ug/dl
TIBC = 250 – 400 ug/dl
Iron saturation = 20 – 55%
Write a SOAP note reporting the iron and protein assessment information.