Paraffinblockeras

Parafinblockeras is a term used in histology and pathology to describe the embedding of tissue samples in paraffin wax to form a solid paraffin block, which serves as a support for thin sectioning and long-term storage.

The process follows fixation with a chemical fixative (commonly formalin), dehydration through a graded series of alcohols, and clearing with a solvent such as xylene or a substitute. The tissue is then infiltrated with molten paraffin at about 56–60°C. When the tissue is completely infiltrated, it is placed in a mold with fresh paraffin and allowed to solidify, creating a paraffin block.

The block can then be trimmed and sectioned with a microtome into thin slices (usually 3–5 micrometers) mounted on glass slides and stained for microscopic examination.

Advantages of paraffin embedding include preserved tissue morphology, compatibility with routine histological staining, and relatively straightforward, cost-effective processing that allows long-term storage of samples. Limitations include the potential for antigen masking or loss of some molecular information, processing artifacts such as tissue shrinkage or air gaps, and the technique not being suitable for all analytical methods, such as certain types of molecular assays or electron microscopy.

Paraffinblockeras is a standard method in diagnostic pathology and research laboratories. Alternatives include cryoembedding for frozen sections, which preserves certain antigens better but requires different handling and storage conditions, and resin embedding for high-resolution ultrastructural studies.