The easy-open, easy-close design of our Flex-Tube provides convenient and reliable sample preparation, centrifugation and storage.  The Eppendorf Flex-Tube is manufactured without the use of slip agents, plasticizers and biocides—substances that have been shown to leach from plastic consumables into the sample and negatively affect bio-assay results.

What is the life expectancy of Eppendorf micro test tubes?At least 5 years at a storage temperature of +5 to +35 °C.

From what material are your micro test tubes manufactured?All of our tubes are manufactured from polypropylene. The polypropylene we use fulfils the specifications of the FDA for the use of plastics for foodstuffs. No metal-based dyes are used.

Do you offer siliconized micro test tubes?Our tube assortment does not include coated or siliconized tubes. In order to keep sample loss caused by the adsorption of sample material on the tube wall to a minimum, we recommend using the Eppendorf Protein LoBind Tubes or Eppendorf DNA LoBind Tubes. These are made of a special type of polypropylene and are manufactured under optimized process conditions.

Is there a chemical resistance overview for the individual micro test tube types?Yes. The Eppendorf Application No. 56 "The best material for original eppis!" includes among other things a detailed material stability overview.

Can Eppendorf micro test tubes be sterilized with ethylene oxide?Yes, this is possible. Please note that the micro test tubes have to be taken out of the packaging for sterilization. In addition, please note that some ethylene oxide will remain in the material after sterilization.

Can your micro test tubes be frozen at -80 °C?Yes. Please refer to the operating manual.

Can your micro test tubes be coated with acrylic resin within the framework of a UV polymerization?Yes, the tubes can withstand UV polymerization. However, we cannot give you any instructions for the procedure.

Can contamination of micro test tubes by bacterial endotoxin be inactivated by autoclaving?No. Bacterial endotoxins (lipopolysaccharide, LPS) are very stable and withstand normal autoclaving at 121 °C. To inactivate LPS, the objects have to be baked at 250 °C, which, of course, is not possible with plastics.

Are the Eppendorf micro test tubes anti-static?Our tubes are not produced from antistatic material, i.e. they are basically not antistatic. But it should be noted that the use of antistatic agents during production will destroy or reduce the wettability of the tubes.

Which Eppendorf micro test tubes are free of DNA?All micro test tubes designated with "PCR clean" are free of human DNA, DNase, RNase and PCR inhibitors. Our Safe-Lock micro test tubes are also available in the "Eppendorf Biopur" purity standard. Due to the special manufacturing processes and the individual blister-packaging, Biopur products are certified "DNA free".

What level of protein binding affinity do your micro test tubes demonstrate?Our micro test tubes are used both in the proteomics area and for storage and transport of many different protein solutions. If you work with low protein concentrations, we recommend using the Eppendorf Protein LoBind Tubes. These tubes are made of a special type of polypropylene and are manufactured under optimized process conditions. In comparison to standard polypropylene tubes, these tubes therefore demonstrate a considerably lower affinity to proteins.

How do you define the temperature entry "RT", for example, as a storage condition for your micro test tubes?Definition of RT (room temperature): +5 to +35 °C.

What is the best way to label Eppendorf micro test tubes?The micro test tube should be clean and free from grease and only labeled on the space provided. Water-resistant felt pens from Steadtler S and F, in black, are the most suitable for this. The writing should be left to dry for at least 2 min.

Do your micro test tubes contain heavy metals?Lead, cadmium, mercury, etc. are well below the prescribed limits of the DIN norm. In the course of the production process it is impossible to avoid the smallest quantities of metal resulting from machine friction.

Overview regarding the centrifugation resistance of Eppendorf tubesSafe-Lock 0.5 ml: 30,000 x g / Biopur 22,000 x g / DNA LoBind 30,000 x g / Protein LoBind 18,000 x g Safe-Lock 1.5 ml: 30,000 x g / Biopur 22,000 x g / DNA LoBind 30,000 x g / Protein LoBind 18,000 x g Safe-Lock 2.0 ml: 25,000 x g / Biopur 22,000 x g / DNA LoBind 25,000 x g / Protein LoBind 18,000 x g 3810X: 30,000 x g 3810: 25,000 x g When using form-fitting tubes and buckets and filling the tubes with their nominal volume, centrifugation of the Safe-Lock Tubes at 25 °C for 30 min at up to 70,000 x g (RT) is possible. Tubes can be centrifuged in a 45°-fixed-angle rotor at 40 °C sample temperature and 90 min with aqueous saline solution (density 1.0 g/ml) up to the above g-forces. The centrifugation resistance depends on the temperature and will be lower at sample temperatures of 40 °C. Liquids with a higher density or affect the stability of the tubes (organic solvents, acids) may reduce the mechanical resilience of the tubes.

Are the Eppendorf tubes autoclavable?Yes, all Eppendorf tubes are autoclavable when open (20 min, 121 °C, 1 bar).