Virtual Nitrogen Balance Practical
Essay by racks • September 30, 2015 • Lab Report • 1,297 Words (6 Pages) • 1,139 Views
Name: Romy Sacks Partners names: Erin Pratt, Laura
Prac date: 1/09/15
Results used: Raw data
Introduction: The aim of the practical session was to ensure the understanding nitrogen balance. Also, it aimed to identify the roles of urea, uric acid and creatinine. Moreover, the practical intended to show the influences of varying levels on protein intake on excretion.
Methods: Refer to instructions
VIRTUAL NITROGEN BALANCE PRACTICAL
Tube | 1 | 2 | 3 | 4 | 5 |
Urea std (0.25 mg/ml) ml | 0.02 | ||||
Urea std (0.5 mg/ml) ml | 0.02 | ||||
Urea std (0.75 mg/ml) ml | 0.02 | ||||
Urea std (1 mg/ml) ml | 0.02 | ||||
Water (ml) | 0.02 | ||||
Urease 1 mg/ml (ml) | 0.1 | 0.1 | 0.1 | 0.1 | 0.1 |
Phenol solution (ml) | 2.5 | 2.5 | 2.5 | 2.5 | 2.5 |
Hypochlorite solution (ml) | 2.5 | 2.5 | 2.5 | 2.5 | 2.5 |
Absorbance 546 nm | 0.006 | 0.171 | 0.359 | 0.535 | 0.696 |
Urea (μg) | 0 | 5 | 10 | 15 | 20 |
Tube | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 |
Sample – high (ml) | 0.02 | 0.02 | ||||||||||
Sample – medium (ml) | 0.02 | 0.02 | ||||||||||
Sample – low (ml) | 0.02 | 0.02 | ||||||||||
Sample – X (ml) | 0.02 | 0.02 | ||||||||||
Sample –Y (ml) | 0.02 | 0.02 | ||||||||||
Sample – Z (ml) | 0.02 | 0.02 | ||||||||||
Urease 1 mg/ml (ml) | 0.1 | 0.1 | 0.1 | 0.1 | 0.1 | 0.1 | 0.1 | 0.1 | 0.1 | 0.1 | 0.1 | 0.1 |
Phenol (120 mM) (ml) | 2.5 | 2.5 | 2.5 | 2.5 | 2.5 | 2.5 | 2.5 | 2.5 | 2.5 | 2.5 | 2.5 | 2.5 |
Hypochlorite solution (ml) | 2.5 | 2.5 | 2.5 | 2.5 | 2.5 | 2.5 | 2.5 | 2.5 | 2.5 | 2.5 | 2.5 | 2.5 |
Absorbance 546 nm | 0.690 | 0.677 | 0.271 | 0.310 | 0.100 | 0.109 | 0.320 | 0.314 | 0.104 | 0.103 | 0.240 | 0.235 |
Urea (μg) |
[pic 1]
Line of best fit: y = 0.03488x + 0.0046
Where y= absorption (546nm) and x= urea (µg)
Sample | Absorbance | µg/20µl | Average µg/20µl | Undiluted µg/20µl X 20 | µg/ml X 50 | Mg/mL / 1000 | Mg/24hr (2L) X 2000 | g/24hr / 1000 | Nitrogen g/24hr X 0.467 |
High | 0.690 | 19.7 | 19.5 | 390 | 19500 | 19.5 | 39000 | 39 | 18.2 |
0.677 | 19.3 | ||||||||
Med | 0.217 | 6.1 | 7.45 | 149 | 7450 | 7.45 | 14900 | 14.9 | 6.95 |
0.310 | 8.8 | ||||||||
Low | 0.100 | 2.7 | 2.85 | 57 | 2850 | 2.85 | 5700 | 5.7 | 2.7 |
0.109 | 3.0 | ||||||||
X | 0.320 | 9.04 | 8.96 | 179.12 | 8956 | 8.95 | 17912 | 17.9 | 8.4 |
0.314 | 8.87 | ||||||||
Y | 0.104 | 2.85 | 2.84 | 58.6 | 2840 | 2.84 | 5680 | 5.68 | 2.65 |
0.103 | 2.82 | ||||||||
Z | 0.240 | 6.75 | 6.68 | 113.6 | 6680 | 6.68 | 13360 | 13.36 | 6.24 |
0.235 | 6.61 |
- Nitrogen in urea sample: CH4N20
- N = 2 X 14 = 28
- Molecular weight urea = 60
- (28/60) X 100 = 46.7
The absorbance values obtained for the creatinine assay: ABSORBANCE VALUES FOR STANDARD CURVE:
Tube | 1 | 2 | 3 | 4 | 5 | 6 |
Creatinine std (100 ⎧g/ml ) (ml) | 0 | 0.2 | 0.4 | 0.6 | 0.8 | 1.0 |
Distilled water | 1.0 | 0.8 | 0.6 | 0.4 | 0.2 | 0 |
Alkaline picrate (ml) | 2.0 | 2.0 | 2.0 | 2.0 | 2.0 | 2.0 |
Distilled water (ml) | 7.0 | 7.0 | 7.0 | 7.0 | 7.0 | 7.0 |
Absorbance 520 nm | 0 | 0.14 | 0.261 | 0.392 | 0.512 | 0.616 |
Creatinine (⎧g) | 0 | 20 | 40 | 60 | 80 | 100 |
ABSORBANCE VALUES FOR ALL OTHER SAMPLES:
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