The care and maintenance of your pipettes is arguably one of the most important routines for working in the lab. Implementing a strict schedule of daily, weekly, monthly, and annual pipette maintenance could mean the difference between purchasing new, expensive equipment and relying on precise measurement instruments. A well-cared for pipette will last longer, provide more accurate results, be calibrated more precisely, and reduce the risk of cross-contamination.
Cleaning pipettes takes time, focus, and practice; the more familiar you become with cleaning techniques, the easier it will become and the better your results will be. Simple pipette maintenance steps should be taken every day in the areas of storage, cleaning, disinfecting, and sterilization in order to ensure the highest quality and the best functioning equipment. The following is a comprehensive guide for properly cleaning your pipettes.
Exterior Cleaning: Most pipettes can be cleaned externally with typical household or laboratory cleaning agents, soaps, or alcohol. By spraying or wiping the exterior of the instrument, the outside of the pipette can be easily cleaned. To ensure full sterilization, let the cleaning solution sit on the pipette for 10-12 minutes before wiping it off.
Interior Cleaning: Cleaning the interior of your pipette can be more time-consuming because it requires full disassembly. Individual parts will need to be cleaned differently depending on the material, shape, size, and purpose.
- Refer to the instruction manual for specific directions.
- Use a long-stemmed cotton swab with a dab of cleaning solution to clean out air passages and remove any clogs.
- Clean and rinse pistons with distilled water and replace them when chipped, pitted, or broken.
- Lightly grease the pistons with the lubricant provided upon purchase.
- Reassemble all parts and check to ensure the pipette operates smoothly.
Contamination Cleaning: If your pipette becomes contaminated with a known substance, there are specific cleaning steps that must be taken depending on the type of substance. Taking the routine cleaning and maintenance steps outlined above will not be sufficient if your pipette is cross-contaminated.
- For aqueous solutions, rinse the contaminated parts with distilled water or 70 percent ethanol and air dry at 60°F.
- For infectious liquids, autoclave the lower section at a temperature of 120°C for 20 minutes and then allow it to return to room temperature before reassembling.
- For organic solvents, allow the substance to evaporate on its own or immerse the part in a detergent and then air dry.
- For radioactive substances, place the pipette in a solution like Decon and then rinse and air dry.
- For proteins, rinse the contaminated parts with a detergent, rinse, and air dry. DO NOT use alcohol as it will set the proteins.
- For nucleic acids, boil lower parts in glycine/HCI buffer (pH 2) for 10 minutes, rinse with distilled water, and air dry.
A well-maintained and clean pipette to a lab technician is just as important as a well maintained and clean instrument to a musician. If a trumpet is dirty, not lubricated, clogged, rusted, scratched, or bent, it will not produce the same results as one that has been well-cared for; the same is true for pipettes. In order to ensure your customers have the most accurate, reliable, and repeatable results, it’s essential to keep your pipette in the best shape possible.