Acetolysis
Definition
Erdtman's 1934 extraction method. The sample is treated with a 9:1 mixture of acetic anhydride and concentrated sulphuric acid, which dissolves cellulose and protoplasm and leaves only the sporopollenin exine for microscopy.
- Chemical agents
- Acetic anhydride and concentrated sulphuric acid (9:1 mixture)
- What it removes
- Cellulose, proteins, protoplasm, and organic matrix
- What survives
- Sporopollenin exine (pollen wall)
- Developed
- 1934 by Erdtman
Common questions
What is acetolysis used for in forensic investigations?+
Acetolysis prepares pollen and spore samples for microscopic examination. The chemical treatment removes the organic clutter so examiners can see the acid-resistant pollen wall (sporopollenin exine) clearly. It's especially useful for extracting pollen from soil and other samples packed with plant debris.
How does acetolysis work?+
The technique mixes acetic anhydride and sulphuric acid, which dissolves cellulose, proteins, and other organic matter in the pollen grain. The sporopollenin exine is resistant to these chemicals and survives intact. What remains is a clean pollen specimen ready for the microscope.
Who developed acetolysis?+
Erdtman developed the method in 1934. It remains the standard laboratory treatment in forensic palynology and botanical evidence processing today.
Related terms
- Aperture
- An opening in the pollen wall through which the pollen tube emerges. Classified by shape into pores (porate), furrows (colpate) and combined...
- Assemblage
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- Blank Control
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- Chain of Custody
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- Diatom
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- Diatom Frustule
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- Diatom Test for Drowning
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- Exotic Marker
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- Forensic Palynology
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- Frustule
- The silica cell wall of a diatom, composed of two overlapping valves (epitheca and hypotheca). Frustules are taxonomically distinctive, chemically resistant to...
- Palynomorph
- Any acid-resistant microscopic organic particle recovered by palynological processing, including pollen grains, spores, dinoflagellate cysts, and fungal spores. Each type carries different...
- Pennate vs Centric
- The two morphological groups of diatoms. Pennate diatoms are elongate with bilateral symmetry (Naviculaceae, Pinnularia, Cymbella). Centric diatoms are circular with radial...
Explained in these topics
- Botanical Evidence Collection and PreservationA laboratory treatment combining acetic anhydride and sulphuric acid that destroys cellulose and proteins in pollen samples, leaving only the resistant sporopo...
- Finds and Artefact ProcessingThe standard laboratory treatment used to prepare pollen and spores for microscopic examination, dissolving the cellulose and organic matrix while leaving the...
- Forensic Palynology Methods and SamplingA chemical treatment with acetic anhydride and sulphuric acid that destroys cellulose and other organic matter while preserving sporopollenin exines. Used to c...
- Pollens and Diatoms in Forensic InvestigationErdtman's 1934 extraction method. The sample is treated with a 9:1 mixture of acetic anhydride and concentrated sulphuric acid, which dissolves cellulose and p...