guide sur la pureté des embouts de pipette

abc of pipette tip purity

What is contamination and how to avoid it?

What are the common contaminants?

• Deoxyribonuclease: Degrades DNA (DNase)
• Ribonuclease: Degrades RNA (RNase)
• Endotoxins: Also known as pyrogens - Lipopolysaccharides, part of cell membranes in Gram-negative bacteria
• Bacteria
• DNA
• Trace metals

What is the source of contamination?

• Production environment
• Human contact in production
• Injection molding
• Raw material

What is the effect on samples?

• Loss of yield in DNA extraction, in PCR and cloning
• Sample loss in ctPCR and translational studies
• Causes fever in humans and animals
• False results in PCR/qPCR and cloning
• False results in trace metal analysis
• Affects growth and well-being of cells in cell-based assays

Removal from tips in lab conditions?

Yes, No, No, Yes, No, No

• Autoclave
• High quality raw material
• Clean room manufacturing
• Automated production without human contact
• Diamond polished tip molds

Which product to choose to avoid contamination?

• High quality standard or filter tips in single tray rack
• High quality sterile standard or filter tips. Standard tips can also be autoclaved for sterility.

Questions to ask when choosing pipette tips:

• Is the purity of tips tested with low enough detection limits? (DNase, RNase & endotoxin)
• What are the certificates of tip purity I need for my workflow?
• Do the pipettes I use support the purity of my samples?
• Are the tips & pipettes best fit to prevent leakage & splashing?
• What is the sterility assurance level of sterile tips? Is the sterility procedure regularly validated?
• Are the pipettes easy-to-clean and autoclave?

Find out more about contamination-free pipetting and other topics at the Pipetting Academy webpage!