1990 年 39 巻 5 号 p. 340-345
A method for quantitatively determining the surfactant component containing linear alkylbenzenesulfonate and alkylethoxylated sulfate as the anionic surfactant and alkylpoly (oxyethylene) ether as the nonionic surfactant, was devised using a two dimensional thin layer chromatography-extraction and densitometry.
This determination method was carried as follows :
The surfactant component was separated by two dimensional chromatography and each spot was extracted by a solvent. The amounts of surfactants were estimated from the optical density of the extracted solution. In the densitometry method, the spot on the thin layer plate was colored by charring. The illuminated area was scanned by a zigzag scanning type densitometer and the amounts of surfactants were estimated from spot integrated values.
Recoveries of five replicated analyses for the two-dimensional thin layer chromatography-extraction method (sample 1.01.5 mg) and-densitometry method (Sample 0.140.22 g) were 93.5-97.9% and 99.6-100.4%, with the standard deviations being 2.63.194 and 1.42.4%, respectively.
The extraction method has advantages in accuracy and simplicity of the procedure compared with densitometry. It thus appears that for the quantitative determination of surfactant components in detergent by thin layer chromatography, densitometry is superior to the extraction method.