Construct a standard curve (it will be a straight line) by taking the mean of the duplicates for each standard.
You are supplied with a set of data for each of the three colorimetric assays and a protein electrophoresis. Guidelines on the interpretation are provided below.
For each colorimetric assay:
- Construct a standard curve (it will be a straight line) by taking the mean of the duplicates for each standard.
- Using this, determine the values of analyte for the patient sample and the quality control, again using the mean of the duplicate absorbances. (The sample blanks will need to be deducted from absorbances for total and direct for the bilirubin assay.)
- Compare the quality control to its expected value to ascertain whether the assay is valid. It should be within 10%.
- If the assay is valid, compare the results for the patient to the reference range in the practical booklet.
- Study the schematic electrophoretic pattern shown in Figure 1 and consider how it could be interpreted.
- Decide whether the patient results are normal or abnormal.
- Using the notes on the Patient Request Form, also provided, consider the meaning of the data.
For the electrophoresis compare the patient to the control serum and comment on the findings. Also try to link the significance of these data with the other assays.
Write the results and a summary of the findings in your logbook.
Patient Request Form
|
Surname Manning |
Forename Christopher |
|
|
DOB 16/02/1951 |
UR X881952 |
NHS |
|
Address 49 Everest Close |
||
|
Letchworth |
||
|
Drs Name K A Anderson |
||
|
Surgery Address Princes Avenue Group Practice, 59 Princes Avenue, Letchworth |
||
|
Clinical History Weight loss EtOH? |
||
|
Tests requested LFTs, γGT
|
||
Total Protein by Biuret
|
Sample |
Concentration (g/L) |
Absorbance 1 |
Absorbance 2 |
|
Standard blank |
0.00 |
0.000 |
0.002 |
|
Standard 1 |
10.00 |
0.070 |
0.064 |
|
Standard 2 |
20.00 |
0.172 |
0.163 |
|
Standard 3 |
40.00 |
0.226 |
0.234 |
|
Standard 4 |
60.00 |
0.385 |
0.387 |
|
Standard 5 |
80.00 |
0.451 |
0.437 |
|
Standard 6 |
100.00 |
0.550 |
0.542 |
|
Patient |
|
0.234 |
0.221 |
|
Quality control |
|
0.275 |
0.263 |
Albumin by Bromocresol green
|
Sample |
Concentration (g/L) |
Absorbance 1 |
Absorbance 2 |
|
Standard blank |
0.00 |
0.000 |
0.000 |
|
Standard 1 |
5.0 |
0.116 |
0.115 |
|
Standard 2 |
10.0 |
0.251 |
0.248 |
|
Standard 3 |
20.0 |
0.374 |
0.372 |
|
Standard 4 |
30.0 |
0.512 |
0.520 |
|
Standard 5 |
40.0 |
0.662 |
0.651 |
|
Standard 6 |
50.0 |
0.810 |
0.823 |
|
Standard 7 |
60.0 |
0.904 |
0.893 |
|
Standard 8 |
70.0 |
1.088 |
1.042 |
|
Patient |
|
0.412 |
0.426 |
|
Quality control |
|
0.521 |
0.518 |
Bilirubin by Jendrassik & Grof method
|
Sample |
Concentration (µM) |
Absorbance 1 |
Absorbance 2 |
|
Standard blank |
0.000 |
0.000 |
0.001 |
|
Standard 1 |
10.0 |
0.030 |
0.032 |
|
Standard 2 |
20.0 |
0.055 |
0.049 |
|
Standard 3 |
35.0 |
0.092 |
0.097 |
|
Standard 4 |
55.0 |
0.158 |
0.162 |
|
Standard 5 |
75.0 |
0.202 |
0.200 |
|
Standard 6 |
90.0 |
0.266 |
0.252 |
|
Patient blank |
|
0.006 |
0.005 |
|
Patient direct |
|
0.015 |
0.016 |
|
Patient total |
|
0.053 |
0.049 |
|
QC blank |
|
0.002 |
0.001 |
|
QC direct |
|
0.068 |
0.061 |
|
QC total |
|
0.211 |
0.198 |
Figure 1: schematic diagram of serum protein electrophoretic pattern for patient and quality control
|
Details of Quality Control Serum |
Expected values for Quality Control Serum |
|
Lot no: 428UE |
Total protein: 47.5 g/L |
|
Expiry Date: 2021-02 |
Albumin: 31.1 g/L |
|
|
Direct bilirubin: 37.7 μmol/L |
|
|
Total bilirubin: 91.2 μmol/L |
Details on sample label: Patient name: Manning, Christopher
Date of birth: 16/02/1951
