In addition to instilling a consciousness about movement from one area to the next, other work skills are critical and key to obtaining accurate results:
- Aseptic technique
- Follow manufacturer directions
- Pipetting skills
Due to the sensitivity of molecular assays, there is little margin for error. Cross-contamination from specimens with large numbers of organism/target nucleic acid can result from the slightest deviation in aseptic technique.
Follow manufacturer directions
- Use aerosol barrier pipette tips or positive displacement pipette devices
- Use sterile disposable pipettes when transferring specimens to testing tubes
- Use RNase-free pipette tips; pyrogen-free tips
- Keep the racks of sterile pipette tips protected from contamination during storage and use
The attentiveness of the technologist during each transfer of specimen material is critical. When working with specimens, only one specimen container should be opened at a time.
Pipetting skills Although many assays which use pre-prepared master mixes have now been introduced, invariably some reagent preparation is required. This often entails the transfer of very small volumes, which leaves no margin of error during pipetting. Attentiveness to accuracy of pipetting is a must.
