Preconcentration Of Parabens Research Articles

Extraction and preconcentration of parabens from the human follicular fluid through dispersive micro solid phase extraction using microporous MIL-68 (In) followed by in-situ effervescence-boosted dispersive liquid-liquid microextraction

For the first time in this study, a microextraction method was developed to perform follicular fluid safety assessment analysis. The drastic importance of follicular fluid safety on the proper nourishment and development of oocytes caused the development of the present method. Since women are regularly exposed to parabens through cosmetics, healthcare, and hygienic products, the infection of body fluids is probable in long-term exposures. Also, for the first time, MIL-68 (In) was applied in an analytical method. Moreover, a new method called in-situ effervescence-boosted dispersive liquid-liquid microextraction was adopted for the simultaneous derivatization and preconcentration of the target parabens. To perform the method, 25 mg of MIL-68 (In) was dispersed into the solution of follicular fluid by vortexing. Then, 1.0 mL of 2-propanol was used to elute the analytes from the absorbent via vortexing. The analyte-enriched organic phase was mixed with 100 µL of acetic anhydride (derivatization agent) and 27 µL 1,2-dibromoethane (extraction solvent) which was swiftly injected into a sodium carbonate solution. Following the centrifugation, the extraction solvent was sedimented at the bottom of a conical bottom glass test tube and an aliquot of it was injected into a gas chromatograph equipped with a flame ionization detector. Wide linear ranges (120–25000 µg L-1), satisfactory extraction recoveries (31–79%) and enrichment factors (31−79), and appreciable limits of detection (7–36 µg L-1) and quantification (25–120 µg L-1) were recorded. The high surface area of MIL-68 (In) (608.82 m2 g-1) and its significantly low average pore diameter (13.829 A°) provide an ideal platform for the extraction of parabens from the complex matrix of follicular fluid.

Hybrid porous material supported in a cellulose acetate polymeric membrane for the direct immersion thin-film microextraction of parabens in water

A simple and sensitive direct immersion thin-film microextraction (DI-TFME) method based on MIL-101(Cr) modified with carbon nanofibers supported in cellulose acetate (CA-MIL-101(Cr)@CNFs) polymeric membrane was developed for the extraction and preconcentration of parabens in environmental water samples. A high-performance liquid chromatography-diode array detector (HPLC-DAD) was used for the determination and quantification of methylparaben (MP) and propylparaben (PP). The factors affecting the DI-TFME performance were investigated using central composite design (CCD). The linearity of the DI-TFME/HPLC-DAD method obtained under optimal conditions was 0.04–0.04–500 µg/L with a correlation coefficient (R2) greater than 0.99, respectively. The limits of detection (LOD) and quantification (LOQ) for methylparaben were 11 ng/L and 37 ng/L; for propylparaben, they were 13 ng/L and 43 ng/L, respectively. The enrichment factors were 93.7 and 123 for methylparaben and propylparaben. The intraday (repeatability) and interday (reproducibility) precisions expressed as relative standard deviations (%RSD) were less than 5%. Furthermore, the DI-TFME/HPLC-DAD method was validated using real water samples spiked with known concentrations of the analytes. The recoveries ranged from 91.5 to 99.8%, and intraday and interday trueness values were less than ±15%. The DI-TFME/HPLC-DAD approach was effectively used for the preconcentration and quantification of parabens in river water and wastewater samples.

Chromium-based metal organic framework for pipette tip micro-solid phase extraction: an effective approach for determination of methyl and propyl parabens in wastewater and shampoo samples

BackgroundA chromium-based metal organic framework was synthesized and employed as an efficient sorbent for pipette tip micro-solid phase extraction and preconcentration of parabens from wastewater and shampoo samples up to sub-ppb level before their spectrophotometric analysis.ResultsFactors affecting preconcentration including volume and type of solvent, amount of sorbent, number of extraction, and volume and pH of samples were optimized employing one-variable-at-a-time and response surface methodology. Obtained analytical characteristics of the method proves its usefulness for analysis of real samples. Linear range of the method for parabens was 1.0–200.0 μg/L. Detection limit of the protocol was 0.24 µg/L for propyl paraben and 0.25 µg/L for methyl paraben. Reproducibility of the protocol defined as % RSD was better than 5.78%. Synthesized adsorbent can be re-used for at least 20 extractions.ConclusionThe method showed a good detection limit and precision for determination of methyl- and propyl-paraben in wastewater and shampoo samples.

Dispersive Liquid–Liquid Microextraction Followed by Magnetic Solid-Phase Extraction for Determination of Four Parabens in Beverage Samples by Ultra-performance Liquid Chromatography Tandem Mass Spectrometry

In this study, a two-step extraction technique was developed for extraction and preconcentration of parabens from beverage samples using ionic liquid dispersive liquid–liquid microextraction (IL-DLLME) and magnetic solid-phase extraction (MSPE). In this IL-DLLME followed by MSPE method, ionic liquid (IL, 1-octyl-3-methylimidazolium hexafluorophosphate) formed hydrophobic microdroplets in beverage samples as an extractant of parabens; after the IL-DLLME process was completed, graphene modified Fe3O4 nanoparticles (Fe3O4@G) were placed to adsorb and isolate IL from the sample solution. After the supernatant was carefully moved, acetonitrile was added to elute the IL containing parabens from Fe3O4@G. The experimental variables affecting the extraction procedure have been systematically studied. Under optimal conditions, the detection limits were less than 1.53 ng/mL and the linear detection ranges were 2–500 ng/mL (R 2 ≥ 0.998) for these analytes. The recoveries for spiked samples were 58.8–89.2% and satisfactory precision (RSD ≤ 4.8%) were obtained.

An ionic liquid loaded magnetically confined polymeric mesoporous adsorbent for extraction of parabens from environmental and cosmetic samples

Schematic illustration of MSPE procedure for paraben analysis using a new ionic liquid loaded magnetically confined polymeric mesoporous material.

Analysis of Paraben Preservatives in Cosmetic Samples: Comparison of Three Different Dynamic Hollow Fiber Liquid-Phase Microextraction Methods

This study focused on a comparison of three different dynamic hollow fiber-based liquid-phase microextraction (DHF-LPME) methods for extraction and preconcentration of parabens from wastewater, toothpaste, cream, and shampoo samples. The first method is two-phase DHF-LPME, in which n-octanol was used as the extraction solvent. The second is three-phase DHF-LPME, in which n-octanol and basic aqueous solution were used as the extraction solvent and acceptor phase, respectively. High-performance liquid chromatography with UV detection (HPLC–UV) was applied for determination of the parabens in both methods. The third method is a recently introduced method; three-phase DHF-LPME based on two immiscible organic solvents (n-dodecane as organic solvent and acetonitrile as an acceptor phase). The quantitative analyses were performed by the use of gas chromatography-mass spectrometry (GC–MS) after injection port derivatization. The effect of different extraction conditions (i.e., extraction solvent, pH, ionic strength, stirring rate, and dynamic and extraction times) on the extraction efficiency of the parabens was investigated and optimized. All the three procedures provide similar working parameters characterized by high repeatability (3.9–6.3 %) and good linearity (correlation coefficient ranging from 0.989 to 0.998). Results of real sample analyses obtained by these three methods were highly correlated. Although all methods provide compatible alternatives for paraben analysis, the three-phase DHF-LPME based on two immiscible organic solvents may be a more appropriate technique due to its higher extraction efficiency and thus lower limits of detection (LODs). LODs for all the parabens ranged from 0.2 to 5.0 μg L−1 using the two first methods combined with HPLC–UV. An improvement in sensitivity of several orders of magnitude was achieved using three-phase DHF-LPME based on two immiscible organic solvents followed by single-ion monitoring GC–MS analyses (0.01–0.2 μg L−1) due to compatibility of this technique with GC instrument.

Simultaneous derivatisation and preconcentration of parabens in food and other matrices by isobutyl chloroformate and dispersive liquid–liquid microextraction followed by gas chromatographic analysis

A simple, rapid and economical method has been proposed for the quantitative determination of parabens (methyl, ethyl, propyl and butyl paraben) in different samples (food, cosmetics and water) based on isobutyl chloroformate (IBCF) derivatisation and preconcentration using dispersive liquid–liquid microextraction in single step. Under optimum conditions, solid samples were extracted with ethanol (disperser solvent) and 200μL of this extract along with 50μL of chloroform (extraction solvent) and 10μL of IBCF was rapidly injected into 2mL of ultra-pure water containing 150μL of pyridine to induce formation of a cloudy state. After centrifugation, 1μL of the sedimented phase was analysed using gas chromatograph-flame ionisation detector (GC–FID) and the peaks were confirmed using gas chromatograph-positive chemical ionisation-mass spectrometer (GC–PCI–MS). Method was found to be linear over the range of 0.1–10μgmL−1 with square of correlation coefficient (R2) in the range of 0.9913–0.9992. Limit of detection (LOD) and limit of quantification (LOQ) were found to be 0.029–0.102μgmL−1 and 0.095–0.336μgmL−1 with a signal to noise ratio of 3:1 and 10:1, respectively.