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To date, knowledge of internal human exposure to BPA and its analogues (particularly bisphenol S and bisphenol F, etc.) remains limited. In the present study, a method involving dispersive solid-phase extraction and LC/MS was proposed to investigate the contamination levels of 28 precursor bisphenols and 9 major metabolites in serum. The critical variables of preparation method were screened out by Plackett-Burman design and further optimized by central composite design. Left in optimal conditions, a total of 286 samples consisting of 153 males and 133 females were analyzed. The results showed that BPA dominated over all the cases with the highest positive rate (82.2% of all the surveyed people), and totally four metabolites (BPA β-D-glucuronide, BPA monosulfate, BPA bis-(β-D-glucuronide) and BPS monosulfate) were detectable. The occurrence of BPA bis-(β-D-glucuronide) in serum is reported for the first time and its higher positive rate and contamination concentrations suggested that it may be a more important metabolite of BPA than others. Negligible potential risk of health effects to blood donors was observed, since the estimated exposure levels (mean 32.1 ng/kg bw/day, 95th 123.2 ng/kg bw/day) were well below far less than the temporary tolerable reference dose of BPA that recommended by the European Food Safety Authority (4 μg/kg bw/day by). The reference level of BPA for healthy population was determined to be 4.09 μg/L via the percentile method.

Correction for ‘In situ controllable synthesis of graphene oxide-based ternary magnetic molecularly imprinted polymer hybrid for efficient enrichment and detection of eight microcystins’ by Sheng-Dong Pan et al., J. Mater. Chem. A, 2015, 3, 23042–23052.

Correction for ‘Synthesis of a monodisperse well-defined core–shell magnetic molecularly-imprinted polymer prior to LC-MS/MS for fast and sensitive determination of mycotoxin residues in rice’ by Sheng-Dong Pan et al., Anal. Methods, 2017, 9, 5281–5292.

Correction for ‘Surface core–shell magnetic polymer modified graphene oxide-based material for 2,4,6-trichlorophenol removal’ by Mei-Lan Chen et al., RSC Adv., 2014, 4, 63494–63501.

Correction for ‘Controlled synthesis of pentachlorophenol-imprinted polymers on the surface of magnetic graphene oxide for highly selective adsorption’ by Sheng-Dong Pan et al., J. Mater. Chem. A, 2014, 2, 15345–15356.

A novel well-designed graphene oxide-based magnetic polymer (GO-Fe3O4@P) has been successfully synthesized via distillation–precipitation polymerization, ring-opening and amidation reactions. The as-prepared GO-Fe3O4@P was further characterized by transmission electron microscopy (TEM), vibrating sample magnetometer (VSM), BET analysis, zeta potential analysis, X-ray photoelectron spectroscopy (XPS), and Fourier transform infrared spectroscopy (FTIR) and the characterization results revealed that core–shell structural Fe3O4@P microspheres were covalently bonded onto the GO sheet. The adsorption characteristics of the GO-Fe3O4@P intended for removal of 2,4,6-trichlorophenol (2,4,6-TCP) were investigated. Batch adsorption studies were carried out to optimize adsorption conditions. The effect of solution pH, adsorption isotherm, kinetics, and thermodynamics was deeply investigated. The results indicated that the adsorption property of GO-Fe3O4@P was highly pH dependent and the adsorption mechanism referred to hydrogen bond and π–π stacking interactions. The adsorption data for 2,4,6-TCP onto GO-Fe3O4@P was well fitted to a Langmuir isotherm. The maximum adsorption capacity (qm) of GO-Fe3O4@P to 2,4,6-TCP was found to be 232.6 mg g−1. Kinetic results showed that the adsorption reached equilibrium within 4 min, 10 min, and 60 min for initial 2,4,6-TCP concentrations of 10 mg L−1, 100 mg L−1, and 500 mg L−1, respectively. The data of adsorption kinetics obeyed the pseudo-second-order rate model well. Thermodynamic parameters such as ΔHθ, ΔSθ, and ΔGθ for the 2,4,6-TCP adsorption onto GO-Fe3O4@P have been estimated, suggesting the adsorption process was endothermic and entropy favored in nature.

In this work, the decolorization of azo dye Orange G (OG) in aqueous solution by aluminum powder enhanced by ultrasonic irradiation (AlP-UI) was investigated. The effects of various operating operational parameters such as the initial pH, initial OG concentration, AlP dosage, ultrasound power and added hydrogen peroxide (H2O2) concentration were studied. The results showed that the decolorization rate was enhanced when the aqueous OG was irradiated simultaneously by ultrasound in the AlP-acid systems. The decolorization rate decreased with the increase of both initial pH values of 2.0–4.0 and OG initial concentrations of 10–80 mg/L, increased with the ultrasound power enhancing from 500 to 900 W. An optimum value was reached at 2.0 g/L of the AlP dosage in the range of 0.5–2.5 g/L. The decolorization rate enhanced significantly by the addition of hydrogen peroxide in the range of 10–100 mM to AlP-UI system reached an optimum value of 0.1491 min−1. The decolorization of OG appears to involve primarily oxidative steps, the cleavage of N N bond, which were verificated by the intermediate products of OG under the optimal tested degradation system, aniline and 1-amino-2-naphthol-6,8-disulfonate detected by the LC–MS.

A reversed-phase high-performance liquid chromatography (RP-HPLC) method was developed for the simultaneous determination of nine food additives, i.e., acesulfame, saccharin, caffeine, aspartame, benzoic acid, sorbic acid, stevioside, dehydroacetic acid and neotame in red wine. The effects of ion-suppressors, i.e., trifluoroacetic acid (TFA) and ammonium acetate (AmAc) on retention behavior of nine food additives in RP-HPLC separation were discussed in detail. The relationships between retention factors of solutes and volume percent of ion-suppressors in the mobile-phase systems of acetonitrile-TFA aqueous solution and acetonitrile-TFA-AmAc aqueous solution were quantitatively established, respectively. The results showed that the ion suppressors had not only an ion suppression effect, but also an organic modification effect on the acidic analytes. The baseline separation of nine food additives was completed by a gradient elution with acetonitrile-TFA(0.01%, v/v)-AmAc(2.5 mmol L(-1)) aqueous solution as the mobile phase. The recoveries were between 80.2 - 99.5% for all analytes with RSDs in the range of 1.5 - 8.9%. The linearities were in the range of 0.2 - 100.0 mg L(-1) with determination coefficients (r(2)) higher than 0.9991 for all analytes. The limits of quantification (LOQs) were between 0.53 - 0.99 mg L(-1). The applicability of the proposed method to detect and quantify food additives has been demonstrated in the analysis of 30 real samples.

A rapid, sensitive and selective high-performance liquid chromatography tandem mass spectrometric method (HPLC/MS–MS) has been developed and validated for the determination of bromadiolone in whole blood using warfarin as an internal standard (IS). Bromadiolone was extracted from the whole blood samples by liquid–liquid extraction with ethyl acetate. Multiple-reaction monitoring (MRM) was used to detect bromadiolone and IS, using precursor→product ion combinations at m / z 527→465 and 307→161, respectively. The calibration curve was linear ( r 2 =0.998) in the concentration range of 0.5–100.0ng/mL with a lower limit of quantification of 0.5ng/mL in whole blood. Intra- and inter-day relative standard deviations (R.S.D.s) were less than 7.5 and 11.9%, respectively. Recoveries of bromadiolone ranged from 82.1 to 85.2%. This method is found to be determined trace bromadiolone in whole blood and can be used in the diagnosis of the poisoned human beings.