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PubMed · 16859980

Spectroscopic study of orange G-beta-cyclodextrin complex and its analytical application.

Huai You Wang·Juan Han·Xia Guang Feng
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Abstract

The mechanism of the inclusion of orange G and beta-cyclodextrin (beta-CD) has been studied by using both spectrophotometry and infrared spectroscopy. Effects of the pH, concentrations of beta-CD, and ionic strength on the inclusion complex of beta-CD and orange G were examined. The result showed that orange G reacts with beta-CD to form a 1:1 host-guest complex with an apparent formation constant of 3.03 x 10(3)mol(-1)l. The thermodynamic parameters of inclusion complex, DeltaG(0), DeltaH(0), and DeltaS(0) were obtained. Based on the enhancement of the absorbance of orange G produced through complex formation, a ratiometric method spectrophotometrically for the determination of orange G in bulk aqueous solution in the presence of beta-CD was developed, which overcome the effect of condition change on the determination of orange G. The linear relationship between the absorbance and orange G concentration was obtained in the range of 1.0 x 10(-5) to 4.0 x 10(-5)mol l(-1), with a correlation coefficient of 0.9998. The detection limit was 3.6 x 10(-6)mol l(-1). The principal advantage of the proposed method is high accuracy because ratiometry was used in measurement.

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AnionsAzo CompoundsCationsHydrogen-Ion ConcentrationOsmolar ConcentrationSpectrophotometry, InfraredTemperatureThermodynamicsbeta-CyclodextrinsJournal Article

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Huai You Wang, Juan Han, Xia Guang Feng. 2006-04-07. Spectroscopic study of orange G-beta-cyclodextrin complex and its analytical application.. https://doi.org/10.1016/j.saa.2006.03.035

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