Table of Contents

Principle

Adenosine ------> Inosine
            ADA
            
NH3 + Nitroprusside + HOCl 

Procedure for Adenosine Deaminase examination

environmental and safety controlsAdenosine MSDS
Ammonium sulfate MSDS

Preparation of ADA reagent

The examination is done on Erbachem

Preparation of ADA reagent for automated measurement

Erbachem

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

ParameterValue
ModeAbs(absorbance)
Sample volume(ul)10
Reagent volume(ul)1000
Filter630 nm
Aspiration Volume(ul)700
Factor1
Decimal place4
Calibration, Result calculation, Quality control and sample examination in Erbachem
Prepare batch of sample as below. This is batch calibration. Refer Calibrator and QC
Standard 60Standard 60Low controlPatient SamplesHigh controlStandard 60
Reagent/SampleCalibrator BlankSample BlankCalibratorSample
Adenosine Buffer1000100010001000
Sample 10
Calibrator 10
Incubate at 37'C for 1 hour
Phenol Reagent50505050
HOCl Reagent200200200200
Incubate at 37'C for 20 minutes
Sample 10
DI Water10
Read at 630 mm
All volumes are in ul
  1. Switch on the incubator and set at 37'C.
  2. Take out the required number of eppendroff cup of adenosine buffer from refrigerator And incubate at 37'C in the incubator for 10 minutes.
  3. Mark ependroff cups test and blank for each sample id, standard (3 cups of T60(60 U/ml NH4+ calibrator) and one cup of water as blank) and control.
  4. Add 10uL sample in respective test cups and 10uL standard in test standard.
  5. Incubate at 37'C for 1 hour.
  6. After 1 hour take out required amount of 1 ml phenol ependroff cup and 8 ml HOCL reagent bottle from refrigerator.
  7. Now in both test cup and blank cup add 50 uL phenol and then 200 uL HOCl.
  8. Incubate for 20 minutes.
  9. And then add 10uL sample in respective blank cups only. In Blank standard add 10uL DI water.
  10. Take reading at 630 nm filter.
  11. Select “Run test” → ADA in Erbachem menu.
  12. When instrument asks “Aspirate water”, aspirate DI water.
  13. When instrument ask for “Aspirate standard”, press 'No'.
  14. When instrument ask for “Aspirate sample”,aspirate test and blank cups and note down the OD of all sample, standard and control.
  15. Enter this OD in spreadsheet and calculate factor with OD of standard .
  16. Calculate results=(Absorbance T-B)X(Average Factor) in spreadsheet.
  17. Evaluate factor and control results. If factor/control results show major deviation from past, rerun batch.
  18. If Sample OD is more than 2.7 OR result is more than 243 U/ml then dilute the sample with 1 part of sample and 2 part of DI water(1:3).

PROCEDURE FOR OPERATING THE INCUBATOR

To start the incubator,

  1. We have to confirm first that the incubator is properly set within the adequate range(36-38 *c).
  2. Then the water within the tray should be noticed if present in adequate amount so that the ependroff cups get partially(75%) submerged in the tray of water. kindly look at the image for observation.
  3. It also should be measured that the temperature of the water is within 36-38*c.
  4. To confirm the proper temperature first it should be calibrated and measured by separate external thermometer.
  5. Once the two requirements are fulfilled we can now keep our samples for further procedure.
  6. The door of the incubator should never be kept open for long and to be closed as soon as possible. And the switch of the incubator present in the clinical biochemistry lab should always be kept “switched ON”.

here is the principle of ADA ada_principle.odt