With the aid of microwave exposure, the time is accelerated from one hour using conventional methods to as little as 10 minutes for bone marrow core biopsies using formic acid. Bone marrow biopsies require as little as 10 minutes exposure time. Standard fixation protocols in formalin take a minimum of four hours at room temperature. Immunostaining is greatly enhanced in microwave-fixed tissue. Time is saved versus conventional 4 hour fixation .
Many laboratories are generally resistant to changes in established procedures.
No control of time in formalin when specimens are received from outside the lab. Immunostaining results may vary due to changing times in formalin and increased cross-linking. First, the manner in which specimens are transported to your laboratory is the most critical factor in controlling pre-fixation time in formalin. Any reference laboratory or laboratory receiving specimens through the mail generally receive these specimens already fixed. The laboratories which process samples biopsied at their own medical center or picked up by a local courier can best utilize microwave fixation.