Low Retention tips
Low Retention tips maximize sample recovery when handling viscous or detergent containing liquids. Any sort of liquid will flow right off these tips thanks to the extremely liquid repellant molecular structure of the tip surface. The tips are available as non-filter Optifit tips in single trays or refill towers or as Safetyspace® Filter Tips.
Viscous or “sticky” samples are often difficult to fully dispense. They tend to adhere to the tip surface, affecting pipetting performance. Examples of such liquids re enzymes, plasma, detergents, and foaming liquids. Low retention tips are especially advantageous when pipetting detergent-containing solutions (e.g. PRC Master mixes, buffers, or enzyme solutions). These solutions have a low surface tension compared to water. Typically, such solutions are not completely repelled from the tip surface, meaning that a liquid film remains after dispensing. This film reduces pipetting accuracy and precision.
The modified surface properties of low retention tips prevent viscous or sticky liquids from adhering to the tip surface. They allow more economical use of scarce or costly reagents and ensure maximum recovery of valuable samples. The optimal and stable liquid recovery improves pipetting accuracy and precision by reducing inconsistent sample retention in the tip.
Small volumes (<10 μl) of aqueous liquids are not well suited for pipetting using low retention tips. The inner wall of the tip is so slippery that the aspirated volumes may remain lower than targeted, or it may be impossible to aspirate the liquid at all.
There are three methods for reducing liquid retention in pipette tips. Highly polished surfaces of tip molds (e.g. diamond polished) Mechanical polishing of the mold with a diamond abrasive, results in the tip’s surface being extremely smooth, in order to prevent samples from adhering to it. The quality of the low retention surface may vary depending on the age of the mold. Plastic additives or post-dipping into surface-modifying chemicals Tips that include additives either within the polymer material or on the plastic surface present the risk of chemical compounds leaching from the tip into the pipetted solutions, which is a contamination risk. Moreover, the dipping process may result in uneven coverage of the tip’s surface, which reduces the reliability of pipetting results. Complete hydrophobic coverage by innovative proprietary technology The most advanced methods, including that used by Sartorius, use an innovative process that provides the tips
with complete hydrophobic coating. Tips produced in this way have high chemical resistance and are of consistent quality.
There is no commonality in the composition or performance of low retention tips by various manufacturers. The chemical composition and surface properties of low retention tips (sometimes called low binding tips) by various manufacturers can differ greatly.
You can use included USB adapter and cable for charging the pipette, this can be used also while pipetting. Also single charging stand for 1 pipette and charging carousel for 4 pipettes are available separately.
How low retention tips are manufactured affects the integrity of the tips and the risk of leaching. Sartorius Low Retention tips don't release chemical compounds even in extreme conditions.
As there are several methods for manufacturing low retention tips, there are also significant differences in terms of their chemical resistance. Sartorius Low Retention tips tolerate extreme chemical conditions without effect to the surface properties.
You should check with the manufacturer whether or not their tips can be autoclaved. Sartorius low retention Optifit tips can be autoclaved in the same way as standard tips (121°C, 20 min, 1 bar) without any effect on performance. Safetyspace Low Retention Filter tips are not autoclavable.
The best practices when pipetting viscous liquids is to use reverse pipetting and slow pipetting speed. You could improve further by switching to low retention tips and to using an electronic pipette.
Pipetting viscous liquids like glycerol, Tween or blood requires special attention to pipetting technique. Aspirate the liquid very slowly and let the liquid settle inside the tip before removing tip from source vessel. Finally dispense very slowly. You can further increase the accuracy by using the reverse pipetting technique and low retention tips. When pipetting blood or other liquids that tend to clog the tip consider the use of widebore pipette tips.
Yes, all Sartorius pipette tips are recyclable. Sartorius Optifit tips are made of pure Polypropylene (PP) and can be recycled or combusted. Safetyspace™ Filter tips additionally include a pure Polyethylene (PE) filter and can also be recycled or combusted. Finally Low Retention pipette tips can be recycled as the above. Please note that pipette tips that have been used need to be evaluated for presence of hazardous materials.
Are low retention tips effective also when pipetting hydrophobic or amphiphilic molecules e.g. phospholipids?
The low retention treatment creates water and oil repellant tips. We've tested the residual liquid amount with 10% SDS to be lower than with some competitors. You should recommend the customer to test the tips.