Sensitive Determination Of Bisphenol Research Articles

Electrochemical investigation of Mn3O4/ZrO2 nanocomposite; a robust sensor platform for the sensitive determination of bisphenol A

ABSTRACT Electrochemical sensing of bisphenol A by Mn3O4/ZrO2 nanocomposite-modified screen printed graphite electrode (SPGE) was explored. Mn3O4/ZrO2 nanocomposite was prepared through a simple method. Field emission-scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and energy-dispersive X-ray spectroscopy (EDS) confirm the successful synthesis of this nanocomposite. The Mn3O4/ZrO2/SPGE exhibited good electrocatalytic performances towards bisphenol A with a sensitivity of about 0.0753 μA μM−1 and a low limit of detection (LOD) (9.0 nM) in the linear ranges of 0.03–375.0 μM. Besides this, the long-time performing stability, reproducibility and repeatability of the sensor are found to be reliable and good. The practical utility of this new sensor was substantially revealed for detecting bisphenol A in real samples. Considering the very good results, it seems that the Mn3O4/ZrO2/SPGE can be considered as a new method in the development of accurate and inexpensive electrochemical sensors.

Rapid and sensitive determination of bisphenol A using aptamer and split DNAzyme

Despite the increasing concern regarding bisphenol A (BPA) as an endocrine disrupting chemical (EDC) upon environmental or human exposure, development of simple method for BPA detection has been hampered, due to the lack of a stable bioreceptor and signal generator. Here, we report a nucleic acid-based rapid and sensitive method for BPA detection, which constitutes a ssDNA aptamer and ssDNAzyme. When the peroxidase-like DNAzyme sequence was split into two parts (one incorporated into the anti-BPA aptamer as a target recognition element and the other into the complementary sequence as a bait), the presence of BPA hindered the association of the split DNA sequence, leading to a reduced signal in the DNAzyme-triggered chemiluminescence (CL). Thus, this NA-based CL measurement permitted the detection of BPA at as low as 5 nM with a broad dynamic range of five orders and with high selectivity towards BPA over other EDCs with structural similarity. With the development of aptamers, our detection method is expected to facilitate studies to monitor EDCs with high simplicity and sensitivity in the field of environmental science.

A novel platform based on graphene nanoribbons/protein capped Au-Cu bimetallic nanoclusters: Application to the sensitive electrochemical determination of bisphenol A

BSA templated Au-Cu bimetallic nanoclusters (Au-Cu@BSA) were synthesized. The characteristics of the prepared bimetallic nanoclusters were demonstrated by UV–Vis absorption, fluorescence spectrometry and transmission electron microscopy. The Au-Cu@BSA was mixed by graphene nanoribbons (GNRs) and Au-Cu@BSA-GNRs was applied as a modifier of glassy carbon electrode (GCE). Also, the properties of the prepared sensors were investigated by cyclic voltammetry, square wave anodic stripping voltammetry and electrochemical impedance spectroscopy. Au-Cu@BSA-GNRs/GCE was employed for the low cost, high efficiency, rapid, selective and sensitive determination of bisphenol A (BPA) as an effective sensing layer of the electrochemical sensor. Upon the optimization of chemical and instrumental parameters, including pH, deposition potential and time, the oxidation peak current was linearly dependent on the concentration of BPA. The dynamic ranges of BPA were linear between 0.01 to 2.0 and 2.0 to 70 μmol L−1, with a limit of detection 0.004 μmol L−1. The Au-Cu@BSA-GNRs/GCE has high selectivity, stability, repeatability, and reproducibility. These results suggest that the constructed sensor has an excellent capacity as an alternative to routine analysis methods for the determination of BPA. The constructed electrode was used for electrochemical determination of BPA in tap water, bottled water, baby bottle and food storage container by the standard addition method. The obtained results indicate the ability of the proposed method to detect BPA in different real sample matrices.

Preparation and Characterization of Graphenized Pencil Lead Electrode for Sensitive Determination of Bisphenol A in Canned Food and Plastic Bottled Drinking Water Samples

Preparation and Characterization of Graphenized Pencil Lead Electrode for Sensitive Determination of Bisphenol A in Canned Food and Plastic Bottled Drinking Water Samples

Magnetic Dummy Template Silica Sol–Gel Molecularly Imprinted Polymer Nanospheres as Magnetic Solid-Phase Extraction Material for the Selective and Sensitive Determination of Bisphenol A in Plastic Bottled Beverages

In this study, a core–shell magnetic dummy molecularly imprinted polymer (MDMIP) was prepared with a novel and simple method. The imprinting layer was synthesized directly on the surface of Fe3O4 by only one step, which avoided further modification on the exterior of magnetic core. 4,4′-Dihydroxybiphenyl (DDBP) was used as dummy template instead of bisphenol A (BPA) to eliminate the effect of template leakage on quantitative analysis. When used as solid-phase extraction sorbent, a rapid, sensitive, and accurate method for the simultaneous extraction, concentration, and determination of trace BPA in plastic bottled beverage samples by MDMIP-SPE coupled with high-performance liquid chromatography (HPLC) was developed. Advantages of such method may be counted as the mild working temperature during the synthesis, simplicity of extraction procedure, avoidance of leakage of template, time-saving, and high binding capacity and affinity. Several parameters affecting the extraction efficiency of the analytes including the sorbent mass, the pH of sample solution, the HAc percentage in the elute, and the desorption time were investigated. Under optimized conditions, the calibration graph was linear over the range of 11.4–4560 ng mL−1 with the limit of detection of 0.083 ng L−1. In addition, the higher enrichment factors (400-fold) and good recoveries (88.6–99.5%) with relative standard deviation (RSD) values less than 9.5% were achieved. Moreover, the developed extraction protocol simplified the process of traditional solid-phase extraction (SPE) provided the possibility for separation and enrichment of BPA from complicated food matrices.

Sensitive determination of bisphenol A, 4-nonylphenol and 4-octylphenol by magnetic solid phase extraction with Fe@MgAl-LDH magnetic nanoparticles from environmental water samples

Abstract Mg-Al-layered double hydroxide (Mg-Al-LDH) modified nanoscale zero-valent iron (NZVI) (Fe@MgAl-LDH) was firstly synthesized and characterized by several techniques. The results showed that the layered double hydroxides were coated on the surface of nanoscale zero-valent iron particles. This new material exhibited good adsorption for bisphenol A, 4-octylphenol and 4-nonylphenol from water samples. Based on these, a sensitive method was developed for the extraction and preconcentration of bisphenol A, 4-octylphenol and 4-nonylphenol using magnetic Fe@MgAl-LDH nanoparticles as the solid phase extraction adsorbents prior to high performance liquid chromatography coupled with variable wavelength detection. Under the optimal conditions, linear responses were achieved in the range of 0.5–200 μg L −1 with the correlation coefficients (r) above 0.999. The detection limits of three analytes were in the range of 0.24–0.34 μg L −1 , and precisions were all below 2.5% (n = 6). The proposed method was evaluated with real water samples and the excellent spiked recoveries in the range of 96.0–99.3% were achieved.

Sensitive determination of bisphenol A based on Ag nanoparticles/polyguanine modified electrode

A quantitative method for detection of bisphenol A (BPA) was set up based on a glassy carbon electrode (GCE) modified with Ag nanoparticles and polyguanine (Ag-PGA). Under the optimum conditions, this modified electrode could remarkably enhance the electrochemical oxidation peak current of BPA, which made this method had wider linear range from 1.0 × 10–8 to 1.0 × 10–4 M, and lower limit of detection of 1.0 × 10–9 M (S/N=3). Moreover, this method has been successfully applied for the determination of BPA in real samples with satisfactory recovery.

Bamboo Fungus-Derived Porous Nitrogen-Doped Carbon for the Fast, Sensitive Determination of Bisphenol A

Biomass-derived carbon materials have been considered as perfect substitutes for the traditional doped carbon materials, owing to its simple synthesis, rich-doped hetero-atoms, low cost and satisfactory electrochemical properties. In this paper, a rich nitrogen-doped carbon (NDC) material derived from bamboo fungus by simple carbonization was firstly applied for the electrochemical determination of Bisphenol A (BPA). NDC showed high catalytic activity towards the BPA oxidation for its rich doped nitrogen, high conductivity and porous structure. The morphology and structure features of NDC were characterized by the transmission electron microscopes and Raman spectrum. Meanwhile, the electrochemical properties of NDC modified glassy carbon electrode (GCE) and the behaviors of BPA on the NDC modified GCE (NDC/GCE) were estimated by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). Under the optimum conditions, differential pulse voltammetry (DPV) was used for the quantitative determination of BPA. A low detection limit (LOD) of 1.068 μM (IUPAC S/N = 3) was obtained within the range of 1.0 μM to 50.0 μM. And the NDC/GCE was further applied for the practical determination of BPA in soil extract samples successfully. The results revealed that the simple and sensitive NDC based platform could be a potential approach for the practical detection of BPA.

Electrochemically co-reduced 3D GO-C60 nanoassembly as an efficient nanocatalyst for electrochemical detection of bisphenol S

Bisphenol S, the most ideal alternative of bisphenol A, has been proved to be toxic towards human. However, up to now, there is no rapid detection method established to cater to the on-site determination of bisphenol S. Herein, we pioneered an electrochemically co-reduced graphene oxide-C60 nanoassembly based electrochemical platform to cover this shortage. This nanoassembly synthesized by simple grinding and electrochemical reduction shows excellent electrocatalytic activity towards bisphenol S, and the novel electroanalytical platform allows a sensitive determination of bisphenol S in the range of 1–100μM with a detection limit of 0.5μM. Moreover, this sensor was utilized to determine bisphenol S in milk, emerging good anti-interference ability and acceptable recovery.

Synergistic Effect of Lithium Perchlorate and Sodium Hydroxide in the Preparation of Electrochemically Treated Pencil Graphite Electrodes for Selective and Sensitive Bisphenol A Detection in Water Samples

AbstractIn this study, pencil graphite electrodes were activated electrochemically in the presence of different supporting electrolytes and used for the selective and sensitive determination of bisphenol A (BPA) in water samples. Synergistic effects of both LiClO4 and NaOH supporting electrolytes on the performance of the electrochemically treated pencil graphite electrode (ETPGE) were demonstrated in the oxidation of BPA. The electrochemical behavior of BPA on the ETPGE showed two irreversible oxidation peaks at 0.744 V and 0.877 V (vs. SCE). The detection limit was determined to be 3.1 nM. This single‐use electrode is a very promising candidate to overcome the passivation problems arising from the oxidation of BPA. The analytical application of the ETPGE was performed in tap and river water samples.

Rapid preparation of robust polyaniline coating on an etched stainless steel wire for solid-phase microextraction of dissolved bisphenol A in drinking water and beverages

A uniform porous polyaniline-coated fiber for solid-phase microextraction was prepared in nitric acid using an etched stainless steel wire as a substrate (figure). It has a large surface area and long service time for the selective extraction and sensitive determination of bisphenol A in complex matrices.

Sensitive determination of bisphenol A in plastic products by derivative voltammetry using an acetylene black paste electrode coated with salicylaldehyde-modified chitosan

A sensitive and reliable electrochemical method was developed for determination of bisphenol A (BPA) in plastic products using an acetylene black paste electrode coated with salicylaldehyde-modified chitosan (denoted as S-CHIT/ABPE). In the second-order derivative linear sweep voltammetry technique, BPA yielded a very sensitive and well-defined oxidation peak at 842 mV in 0.2 mol L−1 HCl solution. Owing to its unique structure and extraordinary properties, S-CHIT/ABPE showed higher accumulation efficiency toward BPA compared with bare ABPE, and significantly enhanced the oxidation peak current of BPA. Under the optimum conditions, the oxidation peak current was proportional to the concentration of BPA over the range of 4.0 × 10−8 mol L−1 ∼ 1.0 × 10−5 mol L−1. The detection limit (S/N = 3) was 2.0 × 10−8 mol L−1. The fabricated S-CHIT/ABPE not only exhibited strong adsorption capacity toward BPA, but also provided remarkable stable and quantitatively reproducible analytical performance. Additionally, this newly-developed method possesses some obvious advantages including high sensitivity, extreme simplicity, rapid response and low cost.

Sensitive determination of bisphenol A base on arginine functionalized nanocomposite graphene film

Arginine (Arg) functionalized graphene (Arg-G) nanocomposite was produced successfully by an environment-friendly method, and the morphology of the nanocomposite was characterized by transmission electron microscopy (TEM), Raman spectra, etc. Based on Arg-G nanocomposite, an electrochemical sensor was fabricated for sensitive detection of bisphenol A (BPA). The electrochemical behaviors of BPA on Arg-G modified glassy carbon electrode (GCE) were investigated by cyclic voltammetry (CV) and differential pulse voltammetry (DPV). Experimental parameters, such as the accumulation potential and time, scan rate, and the pH value of buffer solution were optimized. Under the optimized conditions, the oxidation peak current was proportional to BPA concentration in the range between 5.0nmol/L and 40.0μmol/L with the correlation coefficient of 0.9986 and the limit of detection of 1.1nmol/L (S/N=3). Moreover, the fabricated electrode also exhibited good reproducibility and stability. The proposed sensor was successfully employed to determine BPA in real plastic products and the recoveries were satisfactory.

Using Zr doped TiO2nanotubes for the pre-concentration and sensitive determination of bisphenol A prior to fluorescence spectrometry in water samples

The present study focused on the investigation of the applicability of a new material, Zr doped TiO2 nanotubes, used as the solid phase extraction adsorbent for the enrichment of bisphenol A. The possible impacting parameters on the extraction such as the kind and volume of eluent, sample pH, sample flow rate, and sample volume were investigated in detail. Under the optimal extraction conditions, the proposed method had excellent linear range of 1–80 μg L−1 and the LOD was 0.016 μg L−1. The relative standard deviation at the concentration of 20 μg L−1 (RSDs, n = 6) was 2.9%. Four different real water samples were used for validation, and the spiked recoveries were satisfactory in the range of 102.9–108.8%, and all these results indicated that Zr doped TiO2 nanotubes had much better extraction performance and would be widely used in the future.

Sensitive determination of bisphenol A and bisphenol F in canned food using a solid-phase microextraction fibre coated with single-walled carbon nanotubes before GC/MS

A reliable and sensitive method for simultaneous determination of bisphenol A (BPA) and bisphenol F (BPF) in canned food by gas chromatography-mass spectrometry (GC/MS) is described after extraction and pre-concentration by a new solid-phase microextraction (SPME) adsorbent. The potential of single-walled carbon nanotubes (SWCNTs) as SPME adsorbent for the pre-concentration of environmental contaminants has been investigated in recent years. This work was carried out to investigate the feasibility of SWCNTs as a headspace SPME adsorbent for the determination of bisphenol derivatives in canned food. Potential factors affecting the extraction efficiency, including extraction time, extraction temperature, desorption time, desorption temperature, and salinity were optimized. Calibration curves were linear (r 2≥ 0.994) over the concentration range from 0.30 to 60 µg kg−1. For both target analytes, the limit of detection (LOD) at signal-to-noise (S/N) ratio of 3 was 0.10 µg kg−1. In addition, a comparative study between the SWCNT and a commercial polydimethylsiloxane (PDMS) SPME fibre for the determination of bisphenol derivatives in canned food was conducted. SWCNT fibre showed higher extraction capacity, better thermal stability (over 350°C) and longer life span (over 150 times) than the commercial PDMS fibre. The method was successfully applied to determine BPA in canned food samples which were purchased from local markets. BPA was found in some of the samples within the concentration range from 0.5 to 5.2 µg kg−1.

Voltammetric Determination of Bisphenol A Using an Acetylene Black‐Dihexadecyl Hydrogen Phosphate Composite Film‐Modified Electrode

Herein, acetylene black (AB) was easily dispersed into water in the presence of dihexadecyl hydrogen phosphate (DHP), resulting in a stable and homogeneous AB‐DHP suspension. Then, an AB‐DHP composite film coated glassy carbon electrode (GCE) was constructed after evaporation of water. The electrochemical behavior of bisphenol A was investigated using cyclic voltammetry (CV), linear sweep voltammetry (LSV), and differential pulse voltammetry (DPV). Compared with the unmodified GCE, the AB‐DHP film‐modified GCE not only significantly enhances the oxidation peak current of bisphenol A but also lowers the oxidation overpotential, suggesting that AB‐DHP film‐modified GCE has great potential in sensitive determination of bisphenol A. Based on this, a sensitive and simple electrochemical method was developed after optimization of the experimental parameters such as supporting electrolyte, the amount of AB‐DHP, scan rate, and accumulation time. The linearity is over the range form 2.0×10−8 to 5.0×10−6 mol l−1, and the detection limit is 6.0×10−9 mol l−1. Finally, this method was successfully employed to determine bisphenol A in waste water samples.

Sensitive determination of bisphenol A and alkylphenols by high performance liquid chromatography with pre‐column derivatization with 2‐(4‐carboxyphenyl)‐5,6‐dimethylbenzimidazole

Sensitive determination of bisphenol A and alkylphenols by high performance liquid chromatography with pre‐column derivatization with 2‐(4‐carboxyphenyl)‐5,6‐dimethylbenzimidazole

Sensitive determination of bisphenol A and alkylphenols by high performance liquid chromatography with pre-column derivatization with 2-(4-carboxyphenyl)-5,6-dimethylbenzimidazole.

A new and sensitive high-performance chromatographic method for the determination of bisphenol A and 8 alkylphenols with fluorescence detection is reported. Each phenol was derivatized by reaction with 2-(4-carboxyphenyl)-5,6-dimethylbenzimidazole at 40 degrees C for 60 min. The fluorescence derivatives were separated on a Wakosil 5C18 column (4.0 i.d. x 300 mm, 5 microm) with methanol:water (10:90) as mobile phase (detection wavelength: lambda(ex) 336 nm, lambda(em) 440 nm). The detection limits were in the range of 0.1-10.0 pg/mL in serum. The calibration graphs were linear to 1.0 microg/mL. The relative standard deviations were 7.2-8.9%, respectively. The proposed method was applied to the determination of bisphenol A in mother and infant rat serum.

Sensitive determination of bisphenol A in environmental water by gas chromatography with nitrogen–phosphorus detection after cyanomethylation

A new technique is proposed for the determination of bisphenol A in environmental water. The sample preparation consists of a single-step extraction of bisphenol A from a water sample with methylene chloride and the cyanomethyl derivatization of bisphenol A. 2,2′-Biphenol is used as an internal standard. Bisphenol A and biphenol can be quantitatively converted to their corresponding cyanomethyl ethers, which are then measured by gas chromatography with nitrogen–phosphorus detection. Peak shape and quantification of bisphenol A are excellent, with linear calibration curves over a range of 0.1–100 ng/ml. The detection limit is 0.1 ng/ml in water samples. The average recovery and RSD at a concentration of 5 ng/ml are 89.3 and 4.5%, respectively. The procedure is applicable to the quantification of bisphenol A in tap water, raw water and stream water.