I use the Biofuge Fresco on a routine basis for all centrifugation purposes. The Biofuge is very small and occupies very little space – good for small labs. The Biofuge is also very quiet and is a blessing compared to several other centrifuges that are very noisy, especially when run at high speeds with refrigeration.
The Biofuge can be run from speeds of 2000 rpm to 13000 rpm (or ~16000 g). I use low speeds of about 2000-3000 rpm for pelleting cell aggregates and high speeds, up to 13000 rpm, for several steps in plasmid preparation and precipitated protein separation after dialysis. A quick spin option is also available. The instrument takes very little time to build up to maximum velocity (nearly 13 seconds for reaching 13000 rpm); it takes a little extra time for slowing down to zero.
In my lab, I use the rotor for 1.5 ml centrifuge tubes. We have procured adaptors for using 0.5 ml tubes in the same rotor. There is a separate rotor for 0.5 ml tubes, but I feel the adaptors for those vials should also have been provided. Other rotor types found in the larger centrifuges, such as swinging bucket etc., are not available.
One good feature of this machine is that although it is very small, it comes with refrigeration capability. I find this feature very useful when I carry out plasmid preparations or when I want to centrifuge temperature-sensitive protein samples. Cooling the instrument, however, takes some time (nearly 30 min to reach 4ºC from 30ºC) and therefore, most of the time, I cool the rotor separately by keeping it in the refrigerator. This saves me a lot of time. Models are also available without refrigeration, and they are much smaller in size than the one I have.
Parameters for operation, including speed and temperature can be set easily using the touchpad. A very useful feature of this instrument is that the controls can be changed even when the machine is running. This is useful when I want to perform longer runs at lower rpm following a fast spin – I do not have to stop the instrument for shifting from one speed to another. The instrument can also be put on hold when the run needs to continue for a very long time (especially useful when I want to concentrate protein samples). However, the machine cannot be kept on hold for an indefinite period; the maximum amount of time is 99 minutes. In any run, when 1 minute is left, the time is automatically displayed in seconds.
The machine is not very heavy and consumes little power. It is very sturdy and compact. I have used this centrifuge for DNA, RNA and protein preparations and for harvesting bacterial cells. Overall, I am pleased with its performance and I would recommend this instrument to any lab that carries out microbiological or molecular biology work.
R. Mahalakshmi
Scientist
Bharathiar University
Department of Biochemistry