In just the past few years, the number of microcentrifuges able to cool samples during centrifugation has grown significantly. While this feature had been available in larger-capacity centrifuges for some time, only recently have microcentrifuge manufacturers begun to consider it a central feature of their more sophisticated instruments.
"When they first came out with the microcentrifuge tubes, these little 1.5 ml tubes, people didn't think it was too important to get a refrigerated centrifuge for those," says Lawrence Rosenberg, a biochemist at Montefiore Medical Center, Bronx, N.Y. "But in the past three or four years, everybody's come out with them. It's no novelty anymore."
Before the advent of these refrigerated microcentrifuges, researchers concerned about the temperatures of their samples could move the entire microcentrifuge into a laboratory cold room--if one were available. Beyond the inconvenience, this practice had its limitations.
"You depended on the temperature of the cold room to...