Mercuric chloride-based fixatives (like B-5 or Zenker's fixative) are generally considered among the least suitable for routine IHC due to their very poor preservation of antigenicity for many targets. These fixatives contain heavy metals (mercury) that precipitate proteins and cause extensive, often irreversible denaturation and cross-linking. While they provide excellent nuclear detail for hematopathology (and were once standard for lymph node biopsies), they severely damage or mask many protein epitopes. Even with aggressive antigen retrieval, staining for many common IHC markers can be weak, inconsistent, or completely absent. Furthermore, they leave mercury pigment deposits in tissues that can interfere with interpretation and pose disposal hazards. For these reasons, 10% neutral buffered formalin has become the universal standard for IHC, providing a better balance of morphology and antigen preservation that can be consistently managed with antigen retrieval techniques. Other fixatives like ethanol or acetone are used for frozen sections but are not routine for FFPE.

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Zambia

• loveness Phiri – 1084 pts

• Visual Pathway Lesions
• Positive and Negative Symptoms
• Hallucinations and Delusions
• Antipsychotic Medications
• Emergency: Environmental Emergencies