A rapid microbiopsy system to improve the preservation of biological samples prior to high‐pressure freezing

• Published in: Journal of microscopy (Oxford) 2003-10, Vol.212 (1), p.3-12
• Main Authors: Vanhecke, D., Graber, W., Herrmann, G., Al‐Amoudi, A., Eggli, P., Studer, D.
• Format: Article
• Language: English
• Subjects: Animals; Biopsy; Brain - ultrastructure; Cryofixation; Cryopreservation - instrumentation; Cryopreservation - methods; cryosectioning; Cryoultramicrotomy; electron microscopy; Freeze Substitution; Freezing; high‐pressure freezing; Kidney - ultrastructure; Liver - ultrastructure; microbiopsy; Microscopy, Electron; Muscles - ultrastructure; Plant Leaves - ultrastructure; Pressure; Rats; Specimen Handling - methods; Time Factors
• ISSN: 0022-2720; 1365-2818
• DOI: 10.1046/j.1365-2818.2003.01226.x

Summary A microbiopsy system for fast excision and transfer of biological specimens from donor to high‐pressure freezer was developed. With a modified, commercially available, Promag 1.2 biopsy gun, tissue samples can be excised with a size small enough (0.6 mm × 1.2 mm × 0.3 mm) to be easily transferred into a newly designed specimen platelet. A self‐made transfer unit allows fast transfer of the specimen from the needle into the specimen platelet. The platelet is then fixed in a commercially available specimen holder of a high‐pressure freezing machine (EM PACT, Leica Microsystems, Vienna, Austria) and frozen therein. The time required by a well‐instructed (but not experienced) person to execute all steps is in the range of half a minute. This period is considered short enough to maintain the excised tissue pieces close to their native state. We show that a range of animal tissues (liver, brain, kidney and muscle) are well preserved. To prove the quality of freezing achieved with the system, we show vitrified ivy leaves high‐pressure frozen in the new specimen platelet.