Quantification Of Bisphenol A Research Articles

Simultaneous determination of environmental endocrine disruptors bisphenol A and 4-nitrophenol bleached from food-contacting materials using the spin-ladder compound La2Cu2O5 modified glassy carbon electrode

Environmental endocrine-disrupting chemicals, Bisphenol A (BPA) and 4-Nitrophenol (4-NP), pose significant risks to reproductive health in both animals and humans. Here, we introduce the first utilization of the 4-leg spin ladder compound La2Cu2O5 as an electrode material for electrochemical sensor. Nanostructured La2Cu2O5 was synthesized via a straightforward Sol-Gel method and thoroughly characterized using X-ray photoelectron spectroscopy, high-resolution transmission electron microscopy, and powder X-ray diffraction. La2Cu2O5 nanoparticles modified glassy carbon electrode (GCE) exhibited a significant electrocatalytic activity towards the oxidation of BPA and 4-NP in phosphate buffer saline (pH 7.0). Square wave voltammetry studies revealed lowest detection limits of 3 nM for BPA and 2.6 nM for 4-NP over a wider concentration range of 0.01–500 μM. Notably, this study marks the first utilization of La2Cu2O5 for simultaneous electrochemical detection of BPA and 4-NP, demonstrating its potential in this field. Furthermore, the sensor exhibited good sensitivity, reproducibility, and selectivity towards BPA and 4-NP, even in the presence of similar potential organic and inorganic interferents. Additionally, the newly developed sensor enabled simultaneous quantification of BPA and 4-NP in real samples such as packaged milk, river water, and plastic bottles, achieving recovery rates above 95%. Importantly, our results underscore the leaching of BPA into water from thin and thick plastics at elevated temperatures (40 °C–80 °C), emphasizing the utility of the proposed sensor for rapid and simultaneous detection of BPA and 4-NP in environmental and food matrices.

Voltammetric determination of bisphenol A using modified carbon paste electrode

ABSTRACT Designing effective and accurate methods to determine bisphenol A (BPA) residues is crucial for safeguarding food safety and preserving the environment. The main objective of the present work is to develop a simple and sensitive electrochemical sensor to detect BPA based on a modified carbon paste electrode (CPE). For this, CeO2 nanoparticles (CeO2 NPs) and ionic liquid (IL) were used to modify CPE. Cyclic voltammetry (CV) was utilised as the technique to investigate the electrochemical behaviour of BPA at the surface of various electrodes (unmodified CPE, CeO2 NPs/CPE, ILCPE, and CeO2 NPs/ILCPE). The obtained result showed that the CeO2 NPs/ILCPE exhibited better electrocatalytic performance to BPA oxidation than that observed at other CPEs. For quantification of BPA, differential pulse voltammetry (DPV) was utilised. Under the optimum detection conditions, the CeO2 NPs/ILCPE sensor showed good linearity in the detection of BPA within range 0.02–460.0 µM with a limit of detection (LOD) of 0.01 µM. Finally, the enhanced electrochemical response from CeO2 NPs/IL-modified CPE towards BPA has been used to evaluate the practical application of this sensor. The obtained results (recovery and relative standard deviation (RSD) values) confirmed the applicability of the modified CPE to detect BPA in real samples. Based on the findings, the CeO2 NPs/ILCPE sensor appears to be a suitable platform for BPA determination.

Influence of UV light, ultrasound, and heat treatment on the migration of bisphenol A from polyethylene terephthalate bottle into the food simulant

This research examined the impacts of ultrasound, UV light, storage time, and temperature on the leaching of bisphenol A (BPA) from polyethylene terephthalate (PET) drinking water bottles in Turkey. The initial phase of the investigation encompassed the quantification of BPA in two distinct brands of bottled water. Samples were extracted by solid- phase extraction (SPE) and analyzed by high performance liquid chromatography with fluorescence detection (HPLC‐FLD). According to the results in the first part, the highest BPA levels were found in bottled water. In the second part of the study, 10 to 30 min of ultrasound treatment increased the BPA migration with increased time in simulants. In the first and second weeks of storage at 25 °C, the effect of storage on BPA migration was below the detection limit (<LOD) in simulants. However, at 35 °C and 45 °C, BPA concentration increased with increased temperature. According to these results, increasing the storage temperature to 35 °C and 45 °C increased the BPA pass faster than the increase in storage time. When simulants in PET bottles were exposed to UV light for 1 and 6 h, BPA transitions higher from 6 to 1 h was found in simulants. Except for first-brand water samples, the passing of bisphenol A was found to comply with the European Food Safety Authority (EFSA) criteria in this study.

In Situ Formation of a Relatively Transparent Ion-Associate Liquid Phase from an Aqueous Phase and Its Application to Microextraction/High-Performance Liquid Chromatography-Fluorescence Detection of Bisphenol A in Water.

The design of a simple approach enabling the detection of bisphenol A (BPA) in water samples without the need for large amounts of solvents is of utmost importance. This paper reports a simple method for the separation, concentration, and quantification of BPA in water samples using high-performance liquid chromatography with fluorescence detection (HPLC-FLD) after its microextraction into an in situ formed organic ion-associate (IA) liquid phase (LP). Novel IA phase components without conjugated double bonds, such as benzene rings, were investigated. Ethylhexyloxypropylamine hydrochloride and sodium dodecyl sulfate solutions were added to the water samples to form IAs. The aqueous phase and ion-associate liquid phase (IALP) were separated by centrifugation. The aqueous phase was removed, and the liquid phase was recovered and measured using HPLC-FLD or HPLC-electrochemical detection (ECD). The concentrated phase (IALP) had a relatively low viscosity and could be injected directly into the chromatograph without dissolving it in organic solvents. The detection limits for BPA by HPLC-FLD and HPLC-ECD were 0.009 and 0.3 µg L-1, respectively.

Fast simultaneous electrochemical detection of Bisphenol-A and Bisphenol-S in urban wastewater using a graphene oxide-iron nanoparticles hybrid sensor

In this work, a novel and sensitive electrochemical sensor was developed for the simultaneous determination of low concentration levels of Bisphenol-A (BPA) and Bisphenol-S (BPS) in a secondary effluent from a wastewater treatment plant and surface water. The sensor design involved the utilization of a glassy carbon electrode that was modified with hybrid iron nanoparticles and a nanostructure of graphene oxide. The synthesized material displayed a stable heterostructure, facilitating efficient electronic transfer and exhibiting impressive electrocatalytic capacity. Furthermore, the sensor successfully detected anodic signals of BPA and BPS with a peak separation of 0.28 V, confirming its excellent performance. For method optimization, a chemometric tool based on a Central Composite Face (CCF) design response surface was employed. The optimized conditions yielded an analytical curve with a linear range of 15.0 to 120.0 µmol L−1 for BPA, represented by the equation Iap (µA)= -0.088 + 0.044 (µA L µmol−1) [cBPA], and 20.0 to 70.0 µmol L−1 for BPS, represented by the equation Iap (µA)= -0.367 + 0.025 (µA L µmol−1) [cBPS]. The detection and quantification limits for BPA were established at 12.05 and 36.51 µmol L−1, respectively. Similarly, for BPS, the corresponding values were determined to be 11.63 and 35.24 µmol L−1. The electrochemical method developed was validated by comparing it with the high-performance liquid chromatography coupled to diode array detector (HPLC-DAD) technique. Notably, the electrochemical method demonstrated to be successful in the simultaneous detection and quantification of BPA and BPS in a secondary effluent and surface water.

Palladium nanoparticles anchored MoS2-MXene composite modified electrode for rapid sensing of toxic bisphenol A in aqueous media

Bisphenol A (BPA) is a commonly used, highly toxic organic phenolic that can damage the human nervous, reproductive, and immune systems, and thus, a rapid onsite test method is required to detect BPA in environmental samples. In this research, we coated screen-printed carbon electrodes (SPCEs) with Pd nanoparticles (NPs) anchored on a MoS2-modified MXene nanoarchitecture for the accurate onsite sensing of BPA contamination in aquatic environmental samples. Pd-MoS2-MXene-SPCEs were prepared using a one-step hydrothermal technique followed by chemical reduction. The optimized SPCE had a low Rctof 63 Ω and excellent electrocatalytic efficiency for BPA oxidation and a remarkably high current density at the lowest anodic potential (0.57 V vs. Ag/AgCl) in 0.05 M phosphate buffer (pH 7). The charge-transfer rate (ks) and the saturation absorption capacity (or surface-excess) (Γ) of the Pd-MoS2-MXene-SPCEs were 3.14 s−1 and 5.62 × 10-9 mol cm−2, respectively. Under optimal conditions, square wave voltammetry responses to BPA concentration were linear in the range 5 to 175 nM, and exhibited high sensitivity (16.205 μA nM−1 cm−2) and a detection limit of 0.12 nM (3.3 σ/s). The optimized SPCE exhibited high reproducibility, reusability, and repeatability with a relative standard deviation (RSD) of < 5.0% and excellent stability and retained 89.2% of its initial sensitivity after 30 days of storage for the onsite sensing of BPA. The prepared sensor showed excellent selectivity for the quantification of BPA even in the presence of electrochemically active interfering compounds such as drugs, pollutants, biological substances, and some common cations/anions. Real-time quantitative analysis of BPA in milk and river and lake water samples was performed, and acceptable recoveries were obtained (from 89.1 to 107.8%) with an RSD of 2.2–3.8%, demonstrating an accuracy similar to that of HPLC.

An ultrasensitive electrochemical biosensor for bisphenol A based on aptamer-modified MrGO@AuNPs and ssDNA-functionalized AuNP@MBs synergistic amplification

Bisphenol A (BPA) is a harmful endocrine disruptor, sensitive and rapid quantification of BPA is highly desirable. In this work, a novel synergistic signal-amplifying electrochemical biosensor was developed for BPA detection by using a recognition probe (RP) constructed by BPA aptamer modified gold nanoparticles-loaded magnetic reduced graphene oxide (Aptamer-MrGO@AuNPs), and a signal probe (SP) constructed by BPA aptamer-complementary single-stranded DNA (ssDNA) functionalized methylene blue (MB)-loaded gold nanoparticle (ssDNA-AuNP@MBs). The RP and SP can self-assemble to form a stable RP-SP complex through complementary base pairing. The current intensity of the biosensor correlates with the number of RP-SP complexes. In the presence of BPA, the BPA aptamer can capture BPA with high selectivity and affinity, form an RP-BPA complex and dissociate the RP-SP complex to release SP, resulting in a decrease in the current signal intensity of the biosensor. A single AuNP could be loaded with multiple BPA aptamers and MBs, which improves the recognition efficiency and enhances the signal intensity. Due to the magnetic properties of MrGO@AuNPs, the magnetic separation and adsorption of RP or RP-SP complex is very convenient, enabling all reaction processes to be carried out in solution, which not only improves the mass transfer efficiency, but also simplifies the operation. Under optimal conditions, the developed biosensor had a detection limit as low as 0.141 pg/mL and had been successfully applied to the detection of real environmental water samples. Therefore, the synergistic signal amplification strategy of RP and SP has potential value in the detection of trace pollutants in the water environment.

Paper-Based Analytical Device for One-Step Detection of Bisphenol-A Using Functionalized Chitosan

Bisphenol-A (BPA) is defined as one of the endocrine disrupting compounds. The accurate and inexpensive colorimetric paper-based analytical devices (PADs) are of crucial importance for BPA analysis. In this context, we developed for the first time a new PAD modified with chitosan and sulfamethoxazole (Chitosan-PAD) for the visual detection of BPA in water. The PAD was characterized by Fourier-transform infrared spectroscopy, which confirmed its modification by the functionalized chitosan. A yellow coloration was developed when a small volume of BPA was added to the Chitosan-PAD, allowing for visual and smartphone detection. This new strategy is based on a specific combination of BPA with chitosan and sulfamethoxazole that provides a hight selectivity to the Chitosan-PAD. The proposed PAD was successfully employed in combination with a pre-concentration step for the detection of 0.01 µg mL−1 of PBA with the naked eye using a 10-fold preconcentration factor. The PAD was effectively applied for BPA quantification in water samples with good recoveries. The developed PAD provides a green and cost-effective strategy for the on-site and one-step detection of BPA in water samples.

Monoclinic WO3 nanosheets-carbon nanotubes nanocomposite based electrochemical sensor for sensitive detection of bisphenol A

• WO 3 -CNT nanocomposite was hydrothermally prepared and used as a novel sensing material. • WO 3 -CNT/GCE has enhanced electro-oxidation peak current and reduced potential for BPA. • Improved surface area, good electron transfer and reproducibility of the sensor. • WO 3 -CNT/GCE sensor for BPA has two linear ranges with low detection limit (16.3 nM) • Admirable performance of the sensor for the practical applicability in real samples. A novel and sensitive electrochemical sensor based on monoclinic tungsten trioxide (WO 3 ) nanosheets-carbon nanotubes nanocomposite (WO 3 -CNT) modified glass carbon electrode (GCE) is developed for the direct detection of endocrine disruptor bisphenol A (BPA) in textile sample for the first time. The electrochemical behavior of BPA on the resultant WO 3 -CNT/GCE sensor is investigated using electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV) and chronocoulometry (CC). Under the optimized conditions, the proposed sensor can be adopted to the quantification of BPA using differential pulse voltammetry (DPV), and the electro-oxidation peak current is proportional to the BPA concentration in the range of 0.03–3.0 μM and 3.0–100 μM with a correlation coefficient of 0.9993 and 0.9992, respectively. Moreover, the proposed sensor with a detection limit of 16.3 nM (S/N = 3) exhibits good reproducibility, selectivity and stability, and can be successfully applied to detect the BPA concentrations in real samples (textile, plastic and tap water) with satisfactory recovery (99.4%-110.1%). The present strategy on the hybridization of CNTs and WO 3 enables more opportunities for the electrochemical detection of BPA in the practical applications.

Rapid and simple magnetic solid-phase extraction of bisphenol A from bottled water, baby bottle, and urine samples using green magnetic hydroxyapatite/β-cyclodextrin polymer nanocomposite

Bisphenol A (BPA) is a synthetic organic compound widely used as a starting material in plastics synthesis. The high toxicity of BPA has promoted the development of effective analytical methods for its separation and detection in complex samples. Herein, a novel magnetic nanocomposite consisting of hydroxyapatite and β-cyclodextrin polymer (MHAP/β-CDP) was designed and synthesized by a novel and convenient method for magnetic solid-phase extraction (MSPE) of BPA. The adsorption mechanisms of the MHAP/β-CDP toward BPA were mainly based on the hydrophilic interactions and formation of host–guest inclusion complex. The prepared magnetic nanocomposite was characterized by the vibrating-sample magnetometer (VSM), Fourier transform infrared spectroscopy (FT-IR), energy-dispersive X-ray spectroscopy (EDS), field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD) analysis, and thermogravimetric analysis (TGA). To obtain the best extraction conditions, the extraction parameters were optimized. Under the optimized conditions, MSPE combined with high-performance liquid chromatography-diode array detector (HPLC-DAD) was applied for the determination of BPA in bottled water, baby bottle, and urine samples. The proposed method provided low limits of detection (0.06 ng mL−1) and quantification (0.18 ng mL−1), good linearity (R2 = 0.996) in the range of 0.50–1000.0 ng mL−1, good repeatability (3.2–4.1%, n = 4) and reproducibility (4.9–5.4%, n = 3 days). Furthermore, satisfactory relative recoveries in the range of 97.0–102.0% were obtained for quantification of BPA in bottled water, baby bottle, and urine samples.

Bisphenol A: Quantification in Complex Matrices and Removal by Anaerobic Sludges

The endocrine disruptor bisphenol A (BPA) is one of the most commonly found micropollutants in the environment. However, the biodegradation of BPA under anaerobic (methanogenic) conditions is still an understudied process in wastewater treatment systems. The current study thus addresses the need for a simple and user-friendly analytical method for the rapid and accurate quantification of BPA in complex matrices such as digested and co-digester sludges. We established a microwave-assisted extraction method, followed by derivatization and gas chromatography–mass spectrometry to quantify BPA by comparing it with a deuterated internal standard. The BPA removal capabilities of three digester sludges and three co-digester sludges were examined under mesophilic methanogenic conditions in biogas plants. The endogenous BPA concentration (dry weight) ranged from 1596 to 10,973 µg kg−1 in digested sewage sludges, and from below the limit of quantification to 9069 µg kg−1 in co-digester sludges. When BPA was added to the sludges, the removal capabilities ranged from not significant to 50% after 21 days of incubation. Biogas production was unaffected by the addition of BPA (228 µg kg−1) to the aqueous sludge. The study demonstrated that BPA could be removed under anaerobic conditions in accustomed inoculates. The findings have far-reaching implications for understanding BPA persistence and detoxification under anaerobic conditions.

Selective electrochemical sensor for bisphenol A quantification on carbon electrodes modified with graphitic mesoporous carbon

Owing to the unique electronic properties, high electrical conductivity, and high adsorption capacity of graphitic mesoporous carbon (GMC), a simple strategy was developed to alter the surface of glassy carbon electrodes with a thin layer of GMC. These modified electrodes were applied to detect bisphenol A (BPA) in wastewater samples due to the strong attraction between the GMC-modified surface and BPA. Electrochemical BPA sensing processes were evaluated using different electrochemical techniques, such as differential pulse voltammetry and cyclic voltammetry. For all electrochemical experiments, a distinguished anodic peak at ~ 0.55 V was observed, which was attributed to the enhanced electrochemical BPA oxidation on the surface of the GMC-modified electrode. In addition, the influence of scan rate and electrolyte pH on the electrochemical oxidation of BPA were studied in detail. The electrochemical sensor exhibited a reliable quantification of BPA in a wide range of BPA concentrations (i.e., 20 – 300 μM) and pH (i.e., 5.5 – 8.9) with a sensitivity of 2.93 μA μM−1 cm−2 and a detection limit of 59 nM. Finally, the pre-determined parameters were applied for the quantification of BPA in secondary-treated sewage. The results showed that the developed electrochemical sensor exhibited high BPA recovery in the range of 98.13 – 100.36 %. In summary, the developed electrochemical sensor showed satisfactory reproducibility and sensitivity for accurate BPA detection even in complex matrices, such as sewage.

Magnetic Relaxation Switch Biosensors Based on Self-Assembly of Polystyrene Microspheres and Magnetic Nanoparticles for Detection of Bisphenol A

Bisphenol A (BPA) is a harmful endocrine-disrupting compound. Accordingly, sensitive and rapid methods for BPA quantification are in high demand. In this study, a method was developed for relaxation signal amplification using a magnetic relaxation switch (MRS) biosensor based on the self-assembly of polystyrene microspheres and magnetic nanoparticles to detect BPA in food packaging materials and water samples. Aptamer-functionalized polystyrene microspheres (PS1000–Apt) and complementary DNA-functionalized magnetic nanoparticles (MNP20–cDNA) self-assembled by forming a hybrid chain. The MNP20–cDNA can be captured by the larger size and increased aptamer loading of PS1000–Apt, and then it could be transformed from dispersion to aggregation. The aptamers could capture BPA with high affinity and selectivity, forming stable “PS1000–Apt–BPA” complexes and weakening MNP20–cDNA aggregation. As a result, an altered relaxation signal was obtained. Experimental studies confirmed that the proposed biosensor allowed accurate detection of BPA. Under optimized detection conditions, compared with a limit of detection (LOD) of 0.36 ng/mL for conventional MRS, a detection range (0.1–100 ng/mL) and a lower LOD (0.06 ng/mL) was obtained. Finally, the method was successfully applied in water and polycarbonate (PC) bottle samples for BPA for BPA detection. The PC bottles can be used to hold beverages, juices, and mineral water. However, they may contain a certain amount of BPA, which could be immersed in the solution, thereby affecting human health. The recoveries of spiked samples were 97.0–112.7%, and the relative standard deviation (RSD) values were 3.3–8.7%. These results were consistent with high-performance liquid chromatography studies. Collectively, the developed MRS sensor for relaxation signal amplification based on the self-assembly of polystyrene microspheres and magnetic nanoparticles (PS-MRS) could be a practical method for the ultrasensitive and accurate analysis of BPA in food packaging materials and water samples.

Levels of BPA in makdous, a traditional Syrian food, using solid-phase extraction followed by HPLC

Bisphenol A (BPA), an endocrine disrupter, can migrate from packaging material into food stuff. This research was designed to measure BPA levels in makdous, a traditional Syrian food. Forty three samples of makdous stored in different plastic containers (polyethylene (PE), polypropylene (PP), and unspecified plastic containers) were analyzed every 3 months for one year beginning July 2017. Quantification of BPA was carried out by an RP-HPLC system equipped with fluorescence detector after solid phase extraction. Migration was found in PE and PP plastic containers with slight differences. Statistically significant differences in BPA levels were observed between samples assayed after two weeks of preparation and samples assayed after 12 months (mean 16.32 vs. 38.26 μg/kg, p value=0.003). According to these amounts, BPA levels were all under the specific migration limit of 0.05 mg/kg as newly referred in Regulation (EU) No 2018/213. These levels of exposure would only contribute to 2.15% and 2.75% of the EFSA t-TDI in both men and women respectively based on mean dietary exposure estimates derived from a 24-h dietary information study from 875 participants. Hence there are no concerns about potential health risks from makdous consumption.

In situ generation of H2O2 by a layered double hydroxide as a visible light nano-photocatalyst: Application to bisphenol A quantification

Herein, we report in situ generation of hydrogen peroxide by a nanostructured cobalt-doped zinc-aluminum layered double hydroxide (Co-doped Zn-Al LDH) under visible light irradiation. The Co-doped Zn-Al LDH photocatalyst was synthesized by a facile co-precipitation method and successfully characterized. The hydrogen peroxide was generated in situ by irradiation of the photocatalyst at λ = 525 nm. The generated hydrogen peroxide was reacted with luminol, resulted in a chemiluminescence (CL) emission at λmax = 425 nm. The CL intensity was diminished in the presence of bisphenol A (BPA). As the reduced signal was proportional to BPA concentration, an innovative CL nanosensor was introduced for BPA quantification. Several factors affecting the CL signal were studied and optimized. The CL intensity was decreased linearly with increasing BPA concentration from 0.1 to 20.0 ng mL−1. The limit of detection and relative standard deviations (%RSD, n = 5, BPA concentration: 10.0 ng mL−1) were found to be 0.03 ng Ml−1, and 4.36% and 1.9% for inter- and intra-day assays, respectively. The nano-sensor was effectively utilized for monitoring of BPA in various water samples.

Validation of a simple extraction procedure for bisphenol A identification from human plasma.

The general population is exposed to bisphenol A (BPA) orally, parenterally, transdermally, and environmentally as a result of the use of BPA in food packaging, plastics, and personal care products. The majority of the population nowadays (91–99%) has detectable levels of BPA inside their body. In this study, we successfully performed an inexpensive, rapid, and simple protein precipitation procedure for extraction of BPA from human plasma, followed by analysis by LC-MS/MS. This method was specifically developed for handling large numbers of samples with minimum cost and volume of sample. The developed method was accurate, precise, and reproducible for quantification of BPA from human plasma samples in the concentration range of 10–2000 ng/mL. The method was performed on samples from 150 healthy volunteers who were enrolled in the study. The mean of observed BPA level was 2.22 ± 9.91 ng/mL. Higher BPA levels were observed for females compare to that of males (p-value = 0.002), the BPA levels were higher in participants 33 years of age and older compared to those less than 33 years of age (p-value = 0.000), then the BPA levels higher in subjects with tap water as source of drinking (p-value = 0.005). This method may be valuable for general risk assessment of BPA for a large and varied population because of its efficiency and economical aspects.

Determination of color developers replacing bisphenol A in thermal paper receipts using diode array and Corona charged aerosol detection—A German market analysis 2018/2019

Thermal papers (e.g. point of sale receipts, adhesive labels, tickets) significantly contribute to contamination of paper material cycles and the environment with substances of (eco-) toxicological concern. In particular, they contain color developers like endocrine disrupting bisphenols in typical concentrations of about 1–2 percent per weight (wt%). Bisphenol A (BPA) was used as the common color developer over the last decades, but it will be restricted for thermal paper application in the European Union to a limit of 0.02 wt% from 2020 onwards. Consequently, a variety of BPA substituents such as bisphenol S (BPS) and its derivatives gain importance in thermal paper application. In this study, a rapid, reliable and cost-effective method for identification and quantification of BPA, alternative color developers and related substances like sensitizers is presented based on HPLC separation coupled with diode array detection (DAD) and Corona charged aerosol detection (CAD). Quantification was performed with regard to the intended use of the substances in thermal papers. Besides traditional UV external calibration using reference standards, alternative quantification approaches, in particular UV chromophore concentration for BPS derivatives and CAD universal response technique for low-volatile color developers, were applied and compared in order to allow quantification without reference substances. A market analysis for intended used color developers and sensitizers was performed on thermal paper samples (n = 211) collected in Germany during 2018 and 2019. Pergafast 201 (in 41.7% of the samples) was the most common color developer with concentrations above 0.02 wt%, followed by BPA (36.0%), BPS (13.3%) and other BPS derivatives known as D8, D-90, BPS-MAE and TGSA, that are mainly present in adhesive labels. Sensitizers were determined in over 90% of the samples.

Development and validation of an LC–MS/MS method for the simultaneous determination of bisphenol A and its chlorinated derivatives in adipose tissue

Bisphenol A (BPA) and its chlorinated derivatives (Clx-BPA) are environmental pollutants exhibiting endocrine-disrupting (ED) properties suspected to be involved in the pathogenesis of hormone-dependent cancers, such as breast and prostate cancers. Due to their lipophilic properties, they may accumulate in adipose tissue which could therefore be a suitable matrix to assess long-term exposure to these compounds and relationships with the tumorigenesis of these cancers. An LC-MS/MS assay for the determination of BPA and Clx-BPA in adipose tissue samples was developed and fully validated according to current bioanalytical validation guidelines. Ionization was achieved using an electrospray source operating in the negative mode and quantification of target analytes was obtained in the multiple reaction monitoring mode. Both standard and quality control (QC) samples were prepared in blank adipose tissue samples. Linearity was demonstrated over the ranges 0.125 to 8.000 and 0.0125–0.8000 ng/mL for BPA and Clx-BPA, respectively. Accuracy and precision were demonstrated over the whole concentration range: intra and inter-day bias values were in the 85–114% range and imprecision of the method did not exceed 14%. Lower limits of quantification were validated using QCs at 0.1250 and 0.0125 ng/mL for BPA and Clx-BPA, respectively. Internal standard-corrected matrix effects were comparable in breast and prostate adipose tissues, demonstrating that this method could be used to reliably assay BPA and Clx-BPA in both tissues. The method was sensitive enough to determine BPA and Clx-BPA in breast adipose tissue obtained from women undergoing breast surgery, enabling identification of different patterns of exposure to these ED chemicals. The method enables the reliable quantification of BPA and Clx-BPA in adipose tissue and could be used to assess long-term exposure to these compounds and potential associations with hormone-dependent cancers.

REMOVAL OF BPA FROM LANDFILL LEACHATES USING FENTON-ADSORPTION PROCESS

The objective of this investigation was to identify and quantify the presence of Bisphenol-A (BPA) in raw and treated leachates with the Fenton-adsorption process. BPA is used as a monomer to produce epoxy resins and it is a compound classified as endocrine disruptor. For this reason, it is important to quantify its presence in effluents that will be disposed to the environment to avoid damage to human health and other organisms. The Fenton-adsorption process consisted in the implementation of an advanced oxidation using H2O2 and FeSO4 applied to the raw leachate and subsequently the application of the adsorption process through a column packed with activated carbon. The quantification of BPA was carried out by gas chromatography coupled to mass spectrometry, using liquid-liquid and liquid-solid extraction methods. A recovery percentage study was carried out to validate the extraction methods. Finally, it was found that the leached evaluated contained >12 mg L-1 and at the end of the treatment its concentration was <0.0174 mg L-1.

Quantitative screening for endocrine-disrupting bisphenol A in consumer and household products using NanoAptamer assay

The NanoAptamer assay is a bisphenol A (BPA) quantification method that uses magnetic beads, quantum dot nanoparticles, and a BPA-specific aptamer. In this study, screening of various consumer and household products for BPA was demonstrated utilizing the NanoAptamer assay. First, the experimental conditions suitable for BPA detection using the NanoAptamer assay were examined in terms of incubation time, temperature, and buffer composition. The range of BPA quantification via the NanoAptamer assay was determined to be 0.005–1000 ng/mL of BPA. The selectivity was confirmed by detecting BPA in an analog mixture containing bisphenol S and bisphenol F. Finally, a leaching experiment using 20 consumer and household products classified into 4 categories was performed to demonstrate the capability of the NanoAptamer assay for BPA detection. The experiment was validated by high-performance liquid chromatography analysis (correlation coefficient, r = 0.99).