Automated tissue processing is the process of preparing biological tissue samples for microscopic examination by automatically subjecting them to a series of precisely controlled chemical treatments. This process aims to preserve tissue morphology, making it suitable for sectioning, staining, and ultimately, diagnosis.
Here's a breakdown of the key steps involved in automated tissue processing:
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Fixation: This initial step stabilizes the tissue structure, preventing autolysis (self-digestion) and putrefaction (decay). Formalin is a commonly used fixative.
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Dehydration: Water is removed from the tissue using increasing concentrations of alcohol (e.g., ethanol). This is crucial for subsequent infiltration with hydrophobic embedding media.
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Clearing: Alcohol is replaced with a clearing agent (e.g., xylene) that is miscible with both alcohol and the embedding medium. This makes the tissue transparent.
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Infiltration/Embedding: The tissue is impregnated with a support medium, typically paraffin wax, which provides rigidity and allows for thin sectioning.
The automation of these steps offers several advantages over manual processing:
- Consistency: Reduces variability and ensures reproducible results.
- Efficiency: Processes multiple samples simultaneously, saving time and labor.
- Safety: Minimizes exposure to hazardous chemicals.
- Quality: Improved tissue preservation and sectioning quality.
- Traceability: Automated systems often provide detailed logs of processing parameters, enhancing quality control and facilitating troubleshooting.
Modern automated tissue processors often incorporate vacuum and heat to accelerate the process and improve infiltration. These systems can be programmed to run specific protocols tailored to different tissue types and diagnostic requirements.
