Correction: Extraction of diazinon, haloxyfop-R-methyl, hexaconazole, diniconazole, and triticonazole in cheese samples using a ferrofluid based liquid phase extraction method prior to gas chromatography.

Correction for 'Extraction of diazinon, haloxyfop-R-methyl, hexaconazole, diniconazole, and triticonazole in cheese samples using a ferrofluid based liquid phase extraction method prior to gas chromatography' by Mahdi Rouhi et al., Anal. Methods, 2023, 15, 3043-3050, https://doi.org/10.1039/D3AY00160A.

Extraction of diazinon, haloxyfop-R-methyl, hexaconazole, diniconazole, and triticonazole in cheese samples using a ferrofluid based liquid phase extraction method prior to gas chromatography.

In the present study, a ternary phase solvent extraction combined with dispersive liquid-liquid microextraction was developed for the extraction of diazinon, haloxyfop-R-methyl, hexaconazole, diniconazole, and triticonazole from cheese samples. The extracted analytes were determined using gas chromatography. In this work, first, the analytes were extracted into an organic phase and then enriched using a dispersive liquid-liquid microextraction. Deep eutectic solvent-based ferrofluid was synthesized and used as an extraction solvent in the dispersive liquid-liquid microextraction step, which makes the method fast and green. After optimization of experimental conditions, under the best extraction conditions, limits of detection and quantification were found in the ranges of 0.18-0.39 and 0.6-1.3 ng g-1, respectively. Enrichment factors and extraction recoveries of the analytes ranged from 138-156 and 69-78%, respectively. In the end, the proposed method was successfully applied to assess the studied pesticides in cheese samples.

Preparation of Molecularly Imprinted Magnetic Graphene Oxide-Gold Nanocomposite and Its Application to the Design of Electrochemical Sensor for Determination of Epinephrine.

In this study, a new molecularly imprinted polymer (MIP) based nanocomposite was synthesized then used to determine epinephrine (EPN) by the use of an electrochemical sensor modified by it. Typical techniques for the synthesis of MIP have disadvantages, such as weak binding sites, low mass transfer and low selectivity. One of the ways to improve electrochemical properties is the use of graphene oxide (GR-Ox) and modification of its surface. For this purpose, GR-Ox was initially magnetized (MGR-Ox), then its surface was coated with a silica layer, and gold nanoparticles (AuNPs) were coated on its surface. Subsequently, copolymerization of methacrylic acid (MAA) and N,N'-methylene-bis-acrylamide (MBA) in the presence of EPN was performed on the MGO-AuNPs surface. Afterwards, a selective carbon paste electrode (CPE) with synthetic nanocomposite was fabricated to detect EPN. Under optimal conditions, a linear range from 10-8 to 5.0 × 10-7 M was obtained for the measurement of EPN in urine and blood with a detection limit of 5 × 10-9 M (S/N = 3).

Investigation of the effect of magnetic particles on the Crystal Violet adsorption onto a novel nanocomposite based on κ-carrageenan-g-poly(methacrylic acid).

A novel nanocomposite hydrogel prepared by incorporating Fe3O4 magnetic nanoparticles into the κ-carrageenan-g-poly (methacrylic acid) with in situ polymerization and was characterized by FT-IR, XRD, SEM, TEM and VSM. Synthesized nanocomposite was used to adsorb Crystal Violet (CV) (cationic dye) in aqueous solution in a batch system. The research studies showed that the adsorption of CV can be impressed as a function of contact time, initial concentration of CV, pH and molar ratio of κ-carrageenan to poly(methacrylic acid). CV adsorption tests disclosed that it only takes 15 min to reach the equilibrium and adsorption capacity for this dye was 28.24 mg g(-1). Langmuir isotherm for equilibrium adsorption data was fitted well and the pseudo-second-order model can describe the adsorption kinetics. Thermodynamic parameters of ΔG°, ΔH° and ΔS° showed the endothermic nature of adsorption and a spontaneous process.

Synthesis of a new molecularly imprinted polymer for sorption of the silver ions from geological and antiseptic samples for determination by flame atomic absorption spectrometry.

A new molecularly imprinted polymer (MIP) was synthesized using methacrylic acid (functional monomer), ethylene glycol dimethacrylate (crosslinker), 2,2'-azobisisobutironitril (initiator), silver (Ag) dithizone complex (template), and chloroform (porogenic solvent). This process was a noncovalent, bulk, thermal radical-polymerization. To compare the performance of this polymer, control polymer (nonimprinted polymer) was prepared under well-defined conditions without the use of a template. Extraction experiments were performed on the MIP and a nonimprinted polymer. Then, various parameters were optimized, such as pH, time, concentration of sample, and type of eluent for elution of Ag from polymer. In addition, interfering effects were investigated on the absorption of Ag by the MIP. This polymer was used for the rapid extraction and preconcentration of Ag from an antiseptic and geological sample. Finally, the amount of Ag was measured by flame atomic absorption spectrometry after preconcentration by the synthesized MIP, and results were compared with a direct inductively coupled plasma method. The results showed high performance of this method in preconcentration of Ag.

Synthesis of CarAlg/MMt nanocomposite hydrogels and adsorption of cationic crystal violet.

CarAlg/MMt nanocomposite hydrogels composed of kappa-carrageenan (Car) and sodium alginate (Alg) biopolymers were synthesized by incorporation of sodium montmorillonite (Na-MMt) nanoclay. Acrylamide (AAm), methylenebisacrylamide (MBA), and ammonium persulfate (APS) were used as monomer, crosslinker, and initiator, respectively. The structure and morphology of nanocomposites were characterized by XRD, SEM, and TEM techniques. The XRD results showed exfoliated MMt nanoclay and exfoliation of MMt was confirmed by TEM graph. The resulting nanocomposites were evaluated to remove cationic crystal violet (CV) dye from water. According to data, the adsorption capacity of nanocomposites was enhanced as the clay content was increased. The experimental data were analyzed according to both Langmuir and Freundlich models and experimental maximum adsorption capacity was obtained 88.8 mg g(-1). By studying the effect of pH on the dye adsorption capacity of nanocomposites, it was revealed that the adsorption capacity of nanocomposites was enhanced at acidic pHs as the Na-MMt nanoclay and kappa-carrageenan components were increased.

Copper (II) ion selective liquid membrane electrode based on new Schiff base carrier.

Cu2+ selective PVC membrane electrode based on new Schiff base 2, 2'-[1,9 nonanediyl bis (nitriloethylidyne)]-bis-(1-naphthol) as a selective carrier was constructed. The electrode exhibited a linear potential response within the activity range of 1.0 x 10(-6) - 5.0 x 10(-3) moll(-1) with a Nernstian slope of 29 +/- 1 mV decade(-1) of Cu2+ activity and a limit of detection 8.0 x 10(-7) mol l(-1). The response time of the electrode was fast, 10 s, and stable potentials were obtained within the pH range of 3.5- 6.5. The potentiometric selectivity coefficients were evaluated using two solution method and revealed no important interferences except for Ag+ ion. The proposed electrode was applied as an indicator electrode to potentiometric titration of Cu2+ ions and determination of Cu2+ content in real samples such as black tea leaves and multivitamin capsule.