Microextraction–Colorimetric (Fluorimetric) Determination of Cationic and Anionic Surfactants in Food Products

The purpose of the work was to develop Express methods for determining cationic and anionic surfactants in disinfectants and process solutions. The surfactant concentration was determined visually and colorimetrically by the intensity of color of the indicator zones of paper test strips or by the length of the colored (discolored) zones of test strips laminated in a polymer film. Semi-quantitative determination of surfactants in solutions was carried out by the intensity of color of the zones of indicator test strips pasted on the substrate (test titration on paper). Bromphenol blue was used as an indicator. The titrant was sodium dodecyl sulfate for cationic surfactants and cetylpyridinium chloride for anionic surfactants. Test strips were used for the determination of surfactants in the disinfectant solutions. The concentration in the range of 0.1 – 1.2% was determined by comparing the color with the standard color scale. The duration of the analysis was 3 – 5 min. Quantitative determination of surfactants was carried out by the length of the colored (discolored) zones of test strips glued in a polymer film. As an indicator for cationic surfactants, bromphenol blue (blue zone on the test strip) was used, and for anionic surfactants, an associate of bromphenol blue with cetylpyridinium chloride (discolored zone on the test strip). The determination range of the surfactant made up 16 – 1000 mg/liter. The concentration was determined according to a calibration graph representing the dependence of the length of the blue/discolored zone of the test strips on the concentration of surfactants in the solution. The relative standard deviation of the analysis results does not exceed 0.3; the analysis duration was 20 – 30 min.

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Spectrophotometric determination of cationic and anionic surfactants with anionic dyes in the presence of nonionic surfactants, part II: Development of batch and flow injection methods

Microchimica Acta ◽

10.1007/bf01242700 ◽

1992 ◽

Vol 106 (1-2) ◽

pp. 67-74 ◽

Cited By ~ 13

Author(s):

Shoji Motomizu ◽

Mitsuko Oshima ◽

Yasuhiro Hosoi

Keyword(s):

Spectrophotometric Determination ◽

Flow Injection ◽

Nonionic Surfactants ◽

Anionic Surfactants ◽

Anionic Dyes ◽

Injection Methods ◽

Cationic And Anionic Surfactants

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Influence of anionic surfactants on the sensitisation of the fluorimetric determination of fenproporex

The Analyst ◽

10.1039/an9871201047 ◽

1987 ◽

Vol 112 (7) ◽

pp. 1047-1050 ◽

Cited By ~ 4

Author(s):

Manuel V. Galdú ◽

Miguel de la Guardia ◽

Lorenzo Braco

Keyword(s):

Anionic Surfactants ◽

Fluorimetric Determination

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Phase behavior of cationic and anionic surfactants at low concentrations

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100123878 ◽

1992 ◽

Vol 50 (1) ◽

pp. 694-695

Author(s):

E. Naranjo

Keyword(s):

Phase Behavior ◽

Structural Characterization ◽

Dynamic Systems ◽

Anionic Surfactants ◽

Intermolecular Forces ◽

Stable Form ◽

Surfactant Mixtures ◽

Low Concentrations ◽

Cationic And Anionic Surfactants ◽

General Method

Equilibrium vesicles, those which are the stable form of aggregation and form spontaneously on mixing surfactant with water, have never been demonstrated in single component bilayers and only rarely in lipid or surfactant mixtures. Designing a simple and general method for producing spontaneous and stable vesicles depends on a better understanding of the thermodynamics of aggregation, the interplay of intermolecular forces in surfactants, and an efficient way of doing structural characterization in dynamic systems.

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