Sample preparation procedure for Eicom ENO-20 (NOx Analyzer)

1. Plasma (or Serum)
Add the same volume of methanol.
Mix using a vortex for 10 sec.
Centrifuge at 10,000 G for 10 min.
Inject the collected supernatant.

Change the precolumn after every 50 samples.

Note: Plasma or serum are directly acceptable without the sample prep but the precolumn should be changed after every 10 to 20 samples.

2. Tissue Homogenate
Add methanol at a concentration of 2 ml/g tissue.
Homogenize (in an ice bath, preferentially).
Centrifuge at 10,000 G for 10 min (at 4ºC, preferentially).
Inject the collected supernatant.

Change the precolumn after every 50 samples.

Note: If the concentration is too high, add the same volume of carrier solution to the supernatant.

3. Cell Culture
The same applies as described in #2 above or in direct injection below. In the case of direct
injection, please change the precolumn frequently(every 10 to 20 samples).  Otherwise, replace it after every 50 samples.

4. Urine
Dilute with carrier solution to 50 times the volume and then inject. 

Replace the precolumn after every 50 samples.
 

5. Saliva
Dilute with carrier solution to 10 times the volume and then inject.
NOTE: The precolumn content should be changed after every 50 samples. This is a rough estimation.

6. Microdialysate
Direct Injection: In the case of microdialysate, 100 to 200 samples can be injected per precolumn.