Bottle Top Burettes need TLC Too!
The temptation to become lax in cleaning and maintaining bottletop burettes can lead to real problems. This is why any company using a bottle-top buret for dispensing, metering, titrating or dosing should have a strict and easily understood standard operating procedure (SOP) as part of confirming to good laboratory practice (GLP) within their organization.
Why Bottletop Burette Maintenance is Important
Glass pipettes and their valve-equipped burette cousins should be thoroughly cleaned when switching between reagents or other liquids being dispensed to micro liter (µl) accuracy. No question about it! (If there is a question you have a problem in your SOP manual).
Cleaning procedures for glass tube pipettes and burettes are long and involved, often requiring multiple cleaning and rinsing steps to ensure removal of the previous reagent or other liquids involved. Yet on their defense these lab tools are the best choice when performing analyses covering a variety of tests. This is the reason why labs use either manual bottletop burettes or motor-driven bottletop burettes when handling the same reagent on a continuing basis. Nevertheless this equipment must be cleaned when changing reagents, when using certain reagents or when putting units into storage.
Bottletop Burette Cleaning Steps:
Remove the bottletop burette from the reagent bottle, discharge remaining reagent in the pumping mechanism into an acceptable container. Thoroughly rinse the pumping mechanism with DI or distilled water based on reagent chemistry or in special cases a sterilizing solution.
This does not get you off the hook. Daily cleaning of bottletop burettes should take place
- When there is pumping resistance
- When using solutions prone to crystallization
- When dispensing alkaline solutions or organic solvents
- When dispensing inorganic oxidizing solutions.
What bottletop burette cleaning challenges have you experienced and how were they solved? Please share other ideas or suggestions.
Bob Wilcox is a representative for CAT Scientific, the North American division of CAT-Ing.de.