Due to the increased vapour pressure of methanol we recommend to pre-wet at least 3 times and perform reverse pipetting technique.
For dispensing an organic solvent it is best to use a positive displacement device. Positive displacement principle devices are most suitable for precise and drip-free dispensing of liquids with high vapor pressure. Since the liquid is enclosed in a tip with integrated piston the solvent vapor does not get into direct contact with the instrument.
An adjustment of air-cushion pipettes is required for solutions with a density > 1.2 mg/µL. Note that variable manual pipettes turn into "fixed-volume pipettes" when being adjusted. They can only be adjusted for one volume and not across the entire volume range. Sophisticated manual pipettes have a user adjustment for temporary adjustment purposes. This user adjustment can easily be set back to manufacturer settings without the need for recalibration.
For decontamination of a pipette wipe off the outer surface with disinfectant, DNA/RNA decontamination agent or 70 % isopropanol. After the exposure time of the disinfectant, rinse thoroughly with demineralized water. This step is especially important if subsequent decontamination steps are performed such as UV-light or autoclaving. Some pipettes may be temporarily subjected to UV light under a sterile bench. We recommend the use of a Hg-lamp, 254 nm, 30 W. The distance between lamp and pipette should be approx. 60 cm. Some pipettes are even fully autoclavable.
The RFID chip is used to clearly identify an instrument. Identification data, e.g. serial number or results of quality control test of manufacturer, are stored on the RFID chip. These data can not be changed or deleted.
Tips with low retention properties will grant an advantage especially during pipetting of solutions containing detergents, such as PCR master mixes, enzyme solutions and many buffers. These tips are characterized by significantly improved flow performance, thus achieving more economic use of expensive reagents, while valuable sample material is used effectively. Furthermore, reproducibility is improved, since wetting of the tip is dependent on both user and handling (for example: pipetting speed) and can therefore vary considerably.
The self-sealing mechanism works best with aqueous solutions, most acids and bases. Strong acids and bases might not be blocked properly and increase the risk of damaging the pipette if accidental over-pipetting occurs. For very aggressive solutions we recommend positive displacement systems where the sample is secured in the tip without any contact to the liquid handling instrument.
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