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nchsls:c:biochemistry:document:cholinesetase

Procedure for Cholinesterase examination

*Learn operation of Erba XL-640 and Erbachem.

  • Select equipment
  • Read following documents
referencesCholinesterase Kit literature of RANDOX
Note: When a new lot is opened, verify kit literature with the uploaded version.
Upload newer version when required and make necessary changes in procedure and process
environmental and safety controlsMSDS of CHE Randox Kits
The examination is done on Erbachem and Erba XL-640

ERBA XL-640

  1. Currently, testing of CHE is done in ERBA XL-640.
  2. The reagent is kept in the freezer of refrigerator no.11.
    • NOTE-Preparation Of Reagent Rack
    • Prepare 1 ml reagent aliquot in washed plain vacutee and arrange in thermocol rack with qc 5 cups which is shown below. Every time when sample come, pick one reagent aliquote with one qc 5 cup and run it. Give proper code for QC (520062209)so it will be exported in LJ. if more than one sample run at one time,take only one qc 5 cup and take 2 reagent vacuttee and mix it in one(total volume will be 2 ml) because from 1 ml reagent only 2 tests can be done.
  3. It has to be melted only when sample has to be tested for CHE.
  4. Value of QC 5 (normal range) or QC 8 (abnormal range) are very similar so only one level quality control(QC 5 Normal Range) has to be used as quality control.
  5. Sample as well as QC ( QC 5 ) is diluted 5 times, CHE is selected, testing is done.
  6. Entry of sample is done as it is, no suffix i.e. dil is added.
  7. QC 5 done every time whenever test done.
  8. if more than one sample run at one time,only one qc 5 is need to be done.
  9. Every time before analysis the sample is diluted. For that precaution should be taken. the water to be taken should be clean DI water labelled from the “frige 12” which is QC WATER.

Erbachem

Note: Following instruction is useful only if operator is familiar with Erbachem

ParameterValue
Sample volume(ul)10
Reagent volume(ul)775
Filter405 nm
Aspitation Volume(ul)500
Type of reaction2 point
Decimal place1
Delay time 30sec
Reading time 60sec
Calibration, Result calculation, Quality control and sample examination in Erbachem
Prepare for calibration as below when lot changes or there is relevent NC. Refer Calibrator and QC
testing materialReplicates
Water blank2
Normal Range Calibrator4
Abnormal range Calibrator4
Normal Range Control4
Abnormal range Control4
  1. Run all testing material as sample (as described below at Sample Examination)
  2. Evaluate calibration and QC absorbances in spreadsheet. Compare with past results.
  3. If results are acceptable, enter the factor in the erbachem and set decimal place to zero.

sample examination

  1. Check aspiration volume of 500 microliter in test parameter of CHE.
  2. Run Randox Human assy control-2(QC 5),1 Randox Human assy control-3(QC 8) in each and every batch. See Assigned values of target values of QC here
  3. Take 775 microliter reagent of ependroff cup from deep freeze no.6. See procedure for Preparing CHE epindroff cups.
  4. Add 10 microliter sample to it
  5. Take reading immediately at 405 nm.
  6. Select “Run test” → CHE in Erbachem menu.
  7. When instrument asks “Aspirate water”, aspirate water.
  8. Take reading immediately at 405 nm.
  9. Total time taken for analysis is 90 seconds. (delay time 30 seconds + reading time 60 seconds)
  10. Evaluate QC results. If QC results show major deviation from past, rerun batch.
  11. instructions for determining quantitative results when a result is not within the measurement interval: Dilution of sample with DI water is done in same way as done by Erba XL-640 automatically.
nchsls/c/biochemistry/document/cholinesetase.txt · Last modified: 2022/08/13 07:34 (external edit)