Growth in the cell-free gap |
- The pipette tip is not properly fixed in the center of the well or |
- Pipette tip is tilted or |
- Pipette tip is short |
The cell-free area is not spherical/circular |
- The cover plate is not fixed properly with paper tape or |
- The plate was tempered or |
- The medium and cells have entered under the pipette tip |
Contamination |
- The pipette tips are not sterile/non-autoclaved or |
- The pipette tips were not processed within the hood or |
- The glue/fixative/adhesive used might have contaminated the medium due to over spilling or shaking |
The cover plate does not fix the plate properly |
- The pipette tips are not homogeneously shortened or |
- The pipette tip is not properly fixed in the center of the well |
Results variation |
- The variation in results in mostly due to the density of the cells or |
- Floating cells occupying the NO growth zone |