Importance of purity factors
Importance of purity factors
ATP, a component of every living cell, is used as an indicator for the presence of any biological contamination. Quantifying ATP is already a standard procedure of hygiene monitoring in pharmaceutical industry. ATP-free testing is therefore an additional analysis for sterility testing (complementing the SAL test).
ATP-free consumables are recommended for: Cell culture1, PCR2, applications in microbiology, restriction analytics
Sterility describes an aseptic condition, meaning the absence of living organisms. During sterilization transmissible agents like fungi, bacteria, or viruses, that can affect e.g. cell culture, food but also standard reactions in molecular biology, are effectively eliminated. Sterility is achieved by irradiation. Eppendorf ensures a Sterility Assurance Level (SAL) of 10-6.
Sterile consumables are recommended for: Cell culture1, applications in microbiology, restriction analytics
Most pyrogens are endotoxins which are natural substances that are found in pathogens, such as bacteria. Though not secreted, endotoxins are released during lysis of bacteria. This is why endotoxins are often present with isolated plasmid DNA, where they can interfere in down-stream applications. Endotoxins can also affect growth and function of cell cultures. Within the pharmaceutical industry endotoxins are a threat for cell-based drug-screening, because they render these products unfit for use. Eppendorf applies the LAL test3 to ensure pyrogen-free consumables.
Pyrogen-free consumables are recommended for: Cell culture, cell-based drug screening, cell-based drug development
Bacterial DNA-free (E. coli):
DNA contaminated consumables can lead to false positive signals during PCR. For PCR or applications that will have PCR as a downstream reaction, DNA-free consumables lead to a higher reproducibility of the results.
DNA-free consumables are recommended for: PCR and upstream PCR applications
Human DNA contaminated consumables can lead to false positive signals during PCR in analytic laboratories that deal with human samples. E.g. in forensics it is of highest importance to exclude the presence of human DNA contaminations, since they are often involved in criminal investigations or paternity testing.
Human DNA-free consumables are recommended for: PCR and upstream PCR applications in forensics
RNases are components of every living cell and withstand even autoclaving. These extremely common enzymes degrade RNA, which can quickly lead to 100% loss of the RNA sample. During RNA isolation or other RNA based applications RNA Protection is mandatory for maximum sensitivity and reproducibility.
RNase-free consumables are recommended for: qPCR, reverse transcription, gene expression microarrays, in vitro translation, RNA isolation
PCR inhibitors interfere with the performance of the PCR by generally exerting their effects through direct interaction with DNA or interference with thermo stable DNA polymerases. PCR inhibitors can therefore be an obstacle to successful PCR results. PCR inhibitor-free is mandatory for sensitivity and reproducibility of PCR experiments.
PCR inhibitor-free consumables are recommended for: PCR and upstream PCR applications
1: Maximum safety for your samples will be achieved with Biopur consumables
2: Maximum safety for your samples will be achieved with PCR clean consumables
3: The Limulus Ameobocyte Lysate assay (LAL) detects minimum amounts of endotoxins by using blood from the Horseshoe Crab, which already shows coagulation in the presence of minimum amounts of endotoxins.