There are a wide variety of instruments on the market designed to agitate samples. These can be broken down into 3 categories according to the motion generated. The categories are: rockers, which have a rocking motion, i.e. an oscillation on one axis; rotators, which have a smooth, bidirectional or 3-D, gyratory motion and shakers, which provide a vortexing motion, ranging from gentle rotation to vigorous agitation. In spite of considerable interchangeability, the correct kind of movement is often critical and can affect the outcome of an experiment.
The Boekel Rocker II has the right kind of motion for a wide variety of applications: mixing test tubes, incubations or washes in Northern, Southern and Western blots, gel or membrane staining and destaining, incubation in immunoassays, agglutination tests. Such variability is achieved thanks to the adjustable tilt angle and speed (0o to 20o and 3-25 oscillations/min, respectively). The instrument can be put in a cold room as well as into an incubator and can be loaded with up to 6.6 lbs.
I use the Boekel Rocker II, as well as other rockers, rotators etc., on a daily basis. Of these instruments, the Boekel Rocker II is my favourite. First, the platform area (12” x 12”) is significantly larger than other instruments of comparable price. These larger dimensions allow more samples to be processed at the same time. Second, two "sticky" rubber mats are available: one is smooth and the other is dimpled. This allows virtually any container to shake without the need for tape to secure the samples. In particular, the dimpled mat works really well to secure a wide variety of tubes. I have been using the Boekel Rocker II for a few months, so I cannot comment on its longevity, but the instruments looks heavy duty and is equipped with a metal rotatory mechanism which does not include any fragile plastic parts.
The only negative remark that I have is that the dimpled mat, as well as a stacking tray which doubles the surface area, are sold separately. This means that the two accessories that give the instrument some of its unique features are sold at extra cost! Nonetheless, the price (including the extras) is still relatively competitive and the Rocker II works just great.
Dario Coletti, PhD
Post-Doctoral Fellow
Mount Sinai School of Medicine, NY