Eppendorf purity grades for tips, tubes and plates Summary Eppendorf purity grades for tips, tubes and plates *1 For accurate details regarding resistance to centrifugation, please refer to the respective product pages. Sterility Per definition, a sterile product does not harbor any living organisms on its surface. The degree of sterilization is described by a residual probability of contamination. This probability is expressed as SAL (Sterility Assurance Level). Thus, a SAL value of 10-6 indicates the presence of one non-sterile item among 106 (1,000,000) sterilized items. Importance Sterile products are required whenever the presence of germs may have a negative effect; for example, in the prevention of infection of samples or incorrect test results for microbiological experiments that would be caused by unsterile lab equipment. Pyrogen-(endotoxin) free Thermostable substances (glycoproteins) from the outer membrane of bacteria and other microorganisms can cause fever in humans and impair the growth of cell cultures. Importance Absence of pyrogen prevents endotoxin-based contamination in drug manufacture, cell culture and medical laboratories. Bacterial DNA-free (E. coli): DNA is found in all cells of living entities, and it is the carrier of all genetic information. The highly sensitive PCR technique enables the detection of individual molecules. Importance The presence of DNA could lead to falsepositive results for different applications involving DNA. Note: Autoclaving does not remove traces of DNA. Free of human DNA To eliminate this potential source of contamination, the consumables are tested for the presence of human DNA. Even a single cell (e.g., skin particles) would be detected in the test. Manufacturing is virtually fully automated and monitored by staff wearing protective clothing. Importance Tests for human DNA prevent consumables from containing DNA that could lead to falsepositive results (e.g., genetic tests in forensics) DNase-free DNAses are enzymes which degrade DNA Importance DNAse contaminations can influence DNA analysis RNase-free RNases are enzymes that degrade RNA. These enzymes are extremely resistant, even to autoclaving and irradiation. Importance RNase-free products are an absolute must in the field of molecular biology because RNA is highly sensitive and can be destroyed very quickly by RNases. ATP-free ATP is a part of all living cells; therefore, its presence can indicate biological contamination. Importance The test procedure for the quantitative and qualitative detection of ATP is already an integral part of hygiene monitoring, e.g., in the pharmaceutical industry. Free of PCR inhibitors PCR—the replication of DNA—has developed into one of the most important and commonplace molecular biology methods used in medical diagnostics, genetic counseling and all basic biological research. However, there are also substances that impair this reaction, so lab products must be free of these inhibitors. Importance It is essential that consumables used contain no impurities that could adversely affect PCR. This is particularly crucial for the amplification of minute quantities of genetic substances and for quantitative PCRs. Eppendorf Quality Click for more information... Sterile Click for more information... PCR clean Click for more information... Sterile + PCR clean Click for more information... Biopur Click for more information... |