Cetrimide, determination

A TLC method for determination of quaternary ammonium antiseptics was proposed, using silanized silica plates in combination with triiodide ions and UVV densitometry at 400 nm. The method was applied to cetylpyridinium chloride, cetrimide (197c) and the isomers of benzalkonium chloride (197b)420. 

Alternatively, cetrimide (197c) and cetylpyridinium chloride were determined in industrial and consumer products, by indirect adsorptive stripping voltametry on a dropping mercury electrode425. A rapid method for benzalkonium chloride (197b) in pharmaceutical preparations was based on LLE of the picrate into chloroform in an F1A system and determination of the anion426. 

OH -C Cl < MeS04 < Br < NO3. The shape and thickness of the monolayer of cetrimide (197c) formed at the air-water interface was determined by neutron reflection. The total thickness of the monolayer was estimated to be 2.1 0.2 nm, of which 1.0 nm is immersed in water six water molecules are associated with each molecule of surfactant436. Similar studies were performed for various C10 to (jx alkyltrimethylammonium surfactants. Interpretation of the neutron reflection results included an estimate... 

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