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Table 3 Recommended fixatives discriminated by suitability for each specific method

From: Methods to study organogenesis in decapod crustacean larvae. I. larval rearing, preparation, and fixation

Histological technique Recommended fixatives Acceptable fixatives
External observation: light microscopy and epifluorescence PFA, FASW, Karnovsky’s 75% ethanol
Immunohistochemistry PFA FASW
Micro CT Bouin’s, PFA FASW, Karnovsky’s, 75% ethanol
Scanning electron microscopy FAE, AAF 75% ethanol
Paraffin histology Bouin’s, Karnovsky’s FAE, PFA
Semithin sectioning Bouin’s, Karnovsky’s or FAE followed by OS  
Transmission electron microscopy Karnovsky’s, GA or TA, followed by OS; GAOS  
  1. AAF: 85 ml 100% ethanol, 5 ml glacial acetic acid, 10 ml 37% formaldehyde*
  2. Bouin’s fixative: 10% formaldehyde, 5% glacial acetic acid in saturated aqueous picric acid 1.2%*
  3. FAE: 150 ml 80% ethanol, 60 ml 37% formalin, and 15 ml glacial acetic acid*
  4. FASW: 4% formaldehyde in water from the animal’s habitat
  5. GA: 4% glutardialdehyde in 0.1 M phosphate or cacodylate-buffered saline pH 7.1–7.3*
  6. GAOS: 2–4% glutardialdehyde, 1–2% OsO4 in 0.1 M cacodylate buffer pH 7.1–7.2*
  7. Karnovsky’s solution: 2–4% formaldehyde and glutaraldehyde in 0.1 M buffer (phosphate buffer or cacodylate buffer) pH 7.1 to 7.2*
  8. OS: 0.5–4% osmium tetroxide (OsO4) in 0.1 M buffer*
  9. PFA: 4% paraformaldehyde in 0.1 M phosphate-buffered saline pH 7.4*
  10. TA: 2% tannin, 2% glutardialdehyde in 0.1 M sodium cacodylate buffer pH 7.2*
  11. *Adjust osmolarity as described in "Preparation and fixation" section