WPI’s popular Eagle series of adjustable pipetters have recently been improved in design, appearance and performance. These pipetters have been designed and perfected by WPI scientists working in our US laboratories. Incorporating the latest material technology (patent pending), the piston seal has been replaced with an ultra high molecular weight polyethylene (UHMWPE) that confers at least five times more abrasion resistance than the PTFE used as a piston seal in conventional pipetters (see “Superior Seal” below). The handle has been redesigned to high ergonomic standards and the digital display has been significantly improved. The result is a series of excellent quality pipetters with the same feel and precision as pipetters costing significantly more.
WPI’s Eagle pipetters are brightly color-coded to facilitate quick recognition in the busy laboratory environment. They are UV radiation-resistant, solvent-resistant and the shaft is autoclavable.
Eagle pipetters can be purchased separately or as customs sets of five, six or seven. Custom sets offer you a great price break (up to 38%) while allowing you to choose only those pipetters appropriate for volumes you need in your lab. No more unused, odd-sized pipetters hidden in drawers. At this price everyone in the lab can have his or her own set.

FDA-registered companies adopt quality control procedures that routinely require pipetters to be evaluated, maintained and re-calibrated at least every six months. Non-FDA registered institutions typically perform similar quality control procedures every twelve months or more even frequently. Most pipetter manufacturers’ recommend that pipetters be serviced at least every twelve months. A recent technical report published by a leading USA pipetter manufacturer, found that pipetters evaluated on a routine twelve-month basis exhibited a 20% failure rate in accuracy of volumetric delivery. The same report also stated that 60% of pipetter failure was due to degradation of the piston seal. Failure of the piston itself accounted for another 25% of the total and 15% were due to shaft failure. To reduce the failure rate the report recommends replacing the piston seal every six months.

Traditional pipetter piston seals are made of Teflon due to its low friction characteristic. However, sealing grease is required to maintain a tight tension against the piston. With time, this grease oxidizes and dries out. As this occurs, the Teflon seal begins to deteriorate due to excessive abrasion between the piston and seal. Teflon can also begin to creep (a process known as “cold flow”), losing some of its fit to the piston. The alternative to this problem thus far has been the use of polyethylene (PE) for the piston seal. PE’s elasticity eliminates the need for sealing grease; however, it produces greater friction than Teflon and is less durable.
WPI’s extensive research in this field has resulted in the development of the most durable pipetter seal available.