Gas chromatographic determination of parabens afterin-situderivatization and dispersive liquid-liquid microextraction

Abstract

Summary. Dispersive liquid-liquid microextraction in combination with an in situ derivatization is suggested for parabens sampling and preconcentration. The derivatization was carried out with acetic anhydride under alkaline conditions maintained using dipotassium hydrogen phosphate. The effects of an extraction solvent type, extraction and disperser solvents volume, extraction time, and ionic strength of the solution on the extraction efficiency were investigated. Chlorobenzene containing n-hexadecane as internal standard was used as an extracting solvent and acetone was used as a disperser solvent. The calibration graphs were linear up to 10 mg mL −1 , correlation coefficients were 0.997-0.999, enrichment factors were from 70 for methylparaben to 210 for butylparaben, and detection limits were 22, 4.2, 3.3, and 2.5 μg L −1 for methylparaben, ethylparaben, propylparaben, and butylparaben, respectively. Repeatabilities of the results were acceptable with relative standard deviations up to 11%. A possibility to apply the proposed method for parabens determination in water samples was demonstrated.

Analytical Methodologies for the Determination of Personal Care Products in Water Samples

“…In this sense, classical DLLME has been employed for triclosan and triclocarban [113,114,119,125] and parabens [126,127,133]. In just one case, the parabens were previously derivatized, with anhydride acetic, to increase the extraction efficiency [126].…”

“…In all cases, the ionization is achieved in EI mode. Regarding the employment of other detectors, FID and photoionization detector (PID) were used by Prichodko et al [126] and Abbasghorbani et al [129], respectively, obtaining poor sensitivity in the determination of parabens. However, Shih et al [130] employed an ECD for triclosan determination taking advantage of the good instrumental sensitivity that the chlorine atoms of this compound have in this detector.…”

Gas Chromatographic determination of parabens after derivatization and dispersive microextraction

“…Contradictory opinions on the toxicity and carcinogenicity of parabens [3] According to the literature, methods for preconcentration of parabens, which are based on the singl-drop liquid microextraction combines with silylation [5], the dispersion liquid-liquid microextraction (DLLME) without [6] or with derivatization by acetic anhydride [7], followed by chromatographic determination are known.…”

“…DLLME of acetyl derivatives is no effective for analysis solutions with a high content of inorganic salts (ionic strength of the solution  0,5) [7], although such samples are widely used in pharmaceutical, biological and environmental samples.…”

Evaluation of alcoholic-assisted dispersive liquid-liquid microextraction of bisphenol a in water samples using an experimental design

“…Some sample preconcentration procedures were applied for the pretreatment of BPA-containing samples, such as, single-drop liquid-phase microextraction (SDME) [6], solid-phase extraction (SPE) [7][8][9], liquid-liquid extraction (LLE) [10], stir bar sorptive extraction (SBSE) [11], solid-phase microextraction (SPME) [12,13], liquid-phase microextraction (LPME) [14], and molecularly imprinted solid-phase extraction (MISPE) [15,16]. Recently, a new microextraction method, named dispersive liquid-liquid microextraction (DLLME), introduced by Assadi et al [17], has been used as a powerful preconcentration technique for extraction of verity compounds including BPA [18][19][20][21][22][23][24][25][26][27]. One of the main disadvantages associated with DLLME, however, is that it uses toxic extraction solvents.…”