Determination of SLES in Personal Care Products by Colloid Titration with Light Reflection Measurements

Abstract

The method of colloid titration with poly(diallyldimethylammonium) chloride has been improved to detect the endpoint with an off-vessel light reflectance sensor. The digital color sensor used measures light reflectance by means of light guides, with no immersion into the reaction solution. In such a method, the optical signal is free of disturbances caused by sticky flocs in the solution. The improved automatic titration set was applied for the determination of sodium laureth sulfate (SLES) in industrial batches and commercial personal care products. The sample color and opacity do not disturb the SLES quantification. When the SLES content lies in the range from 5% to 9%, the optimal sample weight is from 6 g to 3 g.

Determination of Calcium in Meat Products by Automatic Titration with 1,2-Diaminocyclohexane-N,N,N’,N’-tetraacetic Acid

“…A further improvement in this direction could be made by using an optical sensor outside the titration beaker instead of an immersion probe. For example, the Cromlaview CR100 industrial color sensor was successfully used in turbidimetric titration [ 57 , 58 ]. The external optical sensor does not come into contact with the test solutions, so it does not require cleaning.…”

Effect of Drinking Water Salt Content on the Interaction between Surfactants and Bacteria

“…Soaps and surfactants are in common use and have been studied rigorously for their physicochemical characteristics ( 4 , 18 , 19 ). Nevertheless, the three-way interactions between surfactants, salts, and bacteria, in the context of bacterial adhesion behavior, are not well understood.…”