Table 6

Comparison of complexity, hands on and total time involved in performing direct ZN, Magnetic bead and concentrated FM.

Direct ZN

Concentrated FM

Magnetic bead-FM


1. Label slides

1. Label slides

1. Label slides


2. Transfer sputum using applicator and prepare smear

2. Transfer sputum to centrifuge tube

2. Attach adhesive wells


3. Air dry

3. Add decontamination agent and mix

3. Add bleach solution to sputum


4. Heat fix

4. Incubate

4. Incubate


5. Transfer slides to staining rack and add stain

5. Add buffer to 50 ml mark

5. Add capture buffer, Magnetic bead and decon agent to tubes


6. Rinse with water and drain

6. Load centrifuge

6. Add thinned sputum to capture tube


7. Add decoloriser

7. Centrifuge

7. Incubate


8. Rinse with water and drain

8. Unload, pour off supernatant and suspend pellet

8. Add suspension to wells, wash and remove water from wells


9. Add counterstain

9. Make smears

9. Remove wells


10. Drain and rinse with water

10. Air dry

10. Air dry


11. Blot back of slides with tissue

11. Heat fix

11. Heat fix


12. Air dry

12. Transfer slides to staining rack and add stain

12. Transfer slides to staining rack and add stain


13. Examine slides under microscope

13. Rinse with water and drain

13. Rinse with water and drain


14. Add decoloriser

14. Add decoloriser


15. Rinse with water and drain

15. Rinse with water and drain


16. Add counterstain

16. Add counterstain


17. Drain and rinse with water

17. Drain and rinse with water


18. Blot back of slides with tissue

18. Blot back of slides with tissue


19. Air dry

19. Air dry


20. Examine slides under microscope

20. Examine slides under microscope


Hands on time (mins)*

34.0

48.5

48.7


Total time (mins)*

74.6

146.6

139.5


* Hands-on time and total time were estimated based on 3 batches of slides prepared (8-10 slides per batch). These times excluded examination times.

Albert et al. BMC Infectious Diseases 2011 11:125   doi:10.1186/1471-2334-11-125

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