CPE–Paptode as a new technique for determination of dyes: application for determination of acid red 151

Abstract

In the present study, a new method for monitoring the signal after cloud point extraction (CPE) of dyes is introduced. The CPE-Paptode method was used to determine acid red 151, as an anionic dye. The method is based on the CPE of dye from aqueous solution, using Triton X-114, diluting the extracted surfactant-rich phase with ethanol and measuring the RGB parameters by special software written in visual basic (VB 6). Parameters, such as pH of the system, the concentration of the dye and surfactant, equilibration temperature and time, as effective parameters on the extraction efficiency and the determination of the dye, were investigated and optimized. Under the optimal conditions, the calibration curve was linear in the range of 0.5-19.0 mg L À1 . Preconcentration of a 15 mL sample gave an enhancement factor of 13.2 and a detection limit of 0.32 mg L À1 . In addition, the effects of some foreign species including cations, anions and dyes were investigated. The method was successfully applied to the determination of the acid red 151 content in aqueous solution. The results and the figure of merits of the proposed method were comparable with those of CPE-spectrophotometry.

Determination of trace amounts of Brown HT as a food dye by a CPE-scanometry method

“…The cloud point extraction method has been successfully employed for the pre-concentration of compounds, such as food samples [18][19][20], environmental samples [8,21], biological samples [21,22], dyes [13,[23][24][25], biomaterials [26] and pharmaceuticals [27,28].…”

“…Auxiliary methods, such as ultrasonic-assisted cloud point extraction (UA-CPE) [29], microwave-assisted cloud point extraction (MA-CPE) [30], CPE-SPE [31], CPE assisted by nanoparticles [32], and stirring-assisted cloud point extraction (SA-CPE) [33], are also applicable. CPE has been shown to be an effective procedure for analyte extraction, pre-concentration and purification that improves the sensitivity, selectivity, detection limit and other analytical characteristics prior to HPLC [34], GC [35], CE [36,37], spectroscopy [38,39], inductively coupled plasma (ICP) [40], atomic absorption spectrometry [41,42], spectrophotometry [43], HPLC-UV [13], paptode [25] and solution scanometry [44][45][46].…”

CPE-Scanometry as a new technique for the determination of dyes: application for the determination of fast green FCF dye and comparison with spectrophotometric results

“…The cloud point extraction technique has been successfully employed for the preconcentration of compounds such as food samples, [4][5][6] environmental samples, 7-10 biological samples, 10,11 dyes, [12][13][14][15] biomaterials 16 and pharmaceuticals. 17,18 This technique could be easily combined with several analytical methods including spectroscopy, 19,20 inductively coupled plasma (ICP), 21 atomic absorption spectrometry, 22,23 chromatography, 12,24 ow injection 25 and paptode.…”

“…17,18 This technique could be easily combined with several analytical methods including spectroscopy, 19,20 inductively coupled plasma (ICP), 21 atomic absorption spectrometry, 22,23 chromatography, 12,24 ow injection 25 and paptode. 15 Auxiliary techniques of ultrasonic-assisted cloud point extraction (UA-CPE), 26 microwave-assisted cloud point extraction (MA-CPE) 27 and stirring-assisted cloud point extraction (SA-CPE) 28 are also applicable. Therefore, extraction with non-ionic surfactant phases could be coupled with highly sensitive and convenient analytical methods.…”

Spectrophotometric Determination of Trace Amounts of Eosin B Dye after Cloud Point Extraction

“…Also, the auxiliary techniques was coupled with this method, some of these are: ultrasonic-assisted cloud point extraction (UA-CPE) 33 , microwave-assisted cloud point extraction (MA-CPE) 34 , stirring-assisted cloud point extraction (SA-CPE) 35 and solvent floatation spectrophotometry 36 . Recently a new method for monitoring of signal after cloud point extraction (CPE) of dyes was introduced by our group researcher 37 . Therefore, extraction with NS phases could be coupled with highly sensitive and convenient analytical methods.…”