Conway Microdiffusion Cell
Definition
A two-compartment glass or ceramic dish with a central well and an outer ring, sealed at the rim. The poison is released as a gas in the outer ring and diffuses into a reagent in the central well over one to three hours at 37 degrees C.
- Time required
- 1 to 3 hours at 37 degrees Celsius
- Key components
- Outer ring (sample + releasing reagent), central well (trapping reagent), sealed lid
Common questions
What is a Conway microdiffusion cell?+
A two-compartment glass or ceramic dish with a central well surrounded by an outer ring. It traps volatile poisons like hydrogen cyanide, carbon monoxide, and alcohols for chemical testing.
How does a Conway microdiffusion cell work?+
The poisoned sample and a releasing reagent go in the outer ring. The poison converts to gas, diffuses across the air gap into a trapping reagent in the central well over one to three hours at 37 degrees Celsius. The trapped compound is then tested by colorimetry.
What poisons can a Conway microdiffusion cell capture?+
Volatile compounds including hydrogen cyanide (HCN), carbon monoxide (CO), and various alcohols. The method relies on the target poison being able to diffuse as a gas at 37 degrees Celsius.
Related terms
- Steam Distillation
- Passing live steam through a sample so that volatile organic compounds co-distil with water at a temperature below their own boiling point....
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- Viscera
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Explained in these topics
- Distillation, Microdiffusion and Dialysis TechniquesA two-compartment glass or ceramic dish with a central well and an outer ring, sealed at the rim. The poison is released as a gas in the outer ring and diffuse...
- Extraction, Isolation and Clean-up of Poisons from VisceraTwo-well glass dish. Sample plus releasing reagent in the outer well, trapping reagent in the inner well, sealed lid. Volatile poison (HCN, CO, alcohols) diffu...