The Heraeus Biofuge Pico is a small, inexpensive desktop centrifuge. Its compact size means that it can be placed almost anywhere in the laboratory. The centrifuge can take two rotors; a standard 24-place 1.5mL/2.0mL tube rotor or a 4/32 place ‘PCR rotor’. The latter can use either four 8x0.2mL PCR strips with lids or 32 individual 0.2mL PCR tubes. The standard rotor can use 0.6 mL, 0.5 mL, 0.4 mL, 0.25 mL and 0.2mL tubes with adapter sleeves (must be purchased separately). In addition, the rotors can be fitted with aerosol-tight lids to prevent sample loss into the centrifuge or the air.
Both rotors have a maximum speed of 13,000rpm, which translates to approximately 16,000g for the standard rotor and 12,850g for the PCR rotor. Both rotors are sturdy but are made from very light plastic (other than the central pin for connecting the rotor to the centrifuge), enabling fast spin-up and spin-down times. From stationary to full speed requires only 15 seconds and from full speed to stationary requires only 12 seconds. The centrifuge is fairly quiet, although not the quietest available. It is rated at not more than 55dBA at full speed.
The centrifuge has a minimum speed of 2,000rpm and this can be increased to full speed in 100rpm increments. Control of the unit and interpretation of its display is intuitive and straight-forward. The unit is microprocessor-controlled with a red LED display indicating time (1-99 minutes or permanent on) and speed (in rpm only). These parameters are changed with the touch of an up or down arrow using the soft-touch buttons on the front the casing. A pulse or ‘quick run’ momentary button allows runs of shorter than one minute by holding the button for as long as required.
The centrifuge itself is composed of a steel body with a plastic outer casing. Despite the steel construction, the centrifuge weighs only 6.7kg and occupies only 23cm x 33cm of surface space. The instrument is easy to clean and maintain; the rotor is easily removed and the bowl can be cleaned quickly and easily.
Our centrifuges have performed well for many years of heavy use in the laboratory. The only fault observed with these units is the lid-lock safety mechanism. Occasionally, the spring on the lid will apply sufficient pressure on the locking mechanism that it is not able to disengage itself at the end of a run. This is easily overcome, however, by applying a very small amount of pressure to the lid, by placing a hand on top of it, while pressing the lid release button.
Scott Coutts
Department of Microbiology
Monash University
Australia