tissue embedding

Histology is the microscopic study of cells and tissue from plants or animals. It typically involves a small amount of tissue or cells positioned on a slide, which is then examined under a microscope. Many methods are used for preparing cells and tissues for viewing. These methods generally include: fixation, dehydration, clearing, embedding, sectioning, and staining. Fixation is the use of chemical fixatives to preserve the structural integrity of the cells. After fixation, the sample is dehydrated with a solvent concentration-gradient to remove water. Next, a clearing agent such as Toluene or Histochoice Clearing Agent is used as a transition fluid between the dehydration solvent and the embedding media. A commonly used embedding medium is Paraffin wax. During embedding, the sample is infiltrated with paraffin and then the wax is allowed to cool and harden. The paraffin provides a supporting matrix for the tissue. The paraffin with the embedded tissue is referred to as a block. The block is placed in a microtome and thin slices, called sections, are cut and placed on a microscope slide. Finally the sections are stained with histological stains to differentiate areas of interest Laboratories can save time and space, and reduce fatigue for the histology technician with these new items in Cole-Parmer’s enhanced line of histology instruments: Cole-Parmer Tissue Embedding Station The new Cole-Parmer® Tissue Embedding Station combines typical histology products into one module, requiring less benchtop space in the histology lab. Its low work surface and comfortable armrest reduces user fatigue. The station comes equipped with a microprocessor-based controller and a user-programmable timer to provide accurate temperature regulation and convenient monitoring of independently controlled heating and cooling elements. It features different zones for paraffin reservoir, warming oven, tissue holding tank, illuminated work stage, and compressor-cooled cold plate that can be programmed to cycle on/off or remain on continuously. The new Cole-Parmer® Tissue Flotation Work Centers and Tissue Float Baths were designed with the histology technologist in mind: their digital temperature sensor does not require user calibration and a bright recessed LED array supplies a high-contrast background for improved tissue viewing without glare. A real-time clock provides time and date stamps for audit logging. Similarly, the new TBS® SHUR/Wave™ Laboratory Microwave accelerates routine specimen fixation to approximately 10 minutes, while processing results in as little as 15 minutes. While fast, the results are also reliable. No xylene or hazardous chemicals are required—providing a safer user experience while saving on costs for use and disposal of reagents. The tissue-processing microwave maintains uncompromised morphology and antigenicity in samples while obtaining superior sectioning characteristics.