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Herein, a novel imprinted solid-phase extraction cartridge was fabricated to investigate the kinetic, thermodynamic, and isothermal parameters for the selective adsorption of Bisphenol A (BPA). The imprinted polymeric cartridges (BMC) for the BPA adsorption were fabricated in the presence of a template and functional monomer using the in situ polymerization technique. To prove the efficiency and selectivity of BMC, the nonimprinted polymeric cartridges (BNC) and the empty polymeric cartridges (EC) were also fabricated with and without functional monomer using the same manner for the preparation of BMC. The characterization of cartridges was performed by elemental analysis, Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET) surface area measurements, and swelling tests. BPA removal studies were performed by analyzing some parameters such as temperature, BPA concentration, flow rate, salt type, and concentration. The highest capacity was determined as 103.2 mg BPA/g polymer for a 0.75 mL/min flow rate of 0.75 M (NH 4 ) 2 SO 4 containing 200 mg/L BPA solution at 50 °C. NaOH (1.0 M) was used as a desorption agent. The reusability performance was examined by performing 10 consecutive cycles. The solid-phase extraction (SPE) performance was also checked to determine the enrichment and extraction recovery factors for tap water and synthetic wastewater samples. Temkin, Langmuir, Freundlich, and Dubinin-Radushkevich isotherm models were applied to BPA adsorption data examining the adsorption mechanism, surface properties, and adsorption degree. The most suitable isotherm model for BPA adsorption was determined as the Langmuir isotherm model. The thermodynamic parameters (Δ G °, Δ H °, and Δ S °) were investigated to reveal the thermodynamics of adsorption. Adsorption thermodynamic parameters (Δ H °, Δ S °, and Δ G °) were calculated using the thermodynamic equilibrium constant (thermodynamic equilibrium constant, K °) values that change with temperature. It was determined that BPA adsorption was spontaneous (Δ G ° < 0) and endothermic (Δ H ° > 0) and entropy increased (Δ S ° > 0) at the temperatures studied in the BPA adsorption process. The rate control step in the adsorption process was examined by applying pseudo-first-order and pseudo-second-order kinetic models to the adsorption data for the investigations of BPA adsorption kinetics, and the pseudo-second-order kinetic model was found to be more suitable for describing BPA adsorption kinetics. In examining the selectivity of cartridges, structural analogues of hydroquinone, phenol, β-estradiol, and 8-hydroxyquinoline were tested., Competing Interests: The authors declare no competing financial interest., (© 2022 The Authors. Published by American Chemical Society.)

In this study, a novel photoluminescence material for the detection of tributyltin (TBT) was developed by using a paper-based nanocomposite system. For this purpose, molecularly imprinted polymeric nanoparticles (MIN) were synthesized with mini-emulsion polymerization technique. Graphene quantum dots obtained by the hydrothermal pyrolysis were immobilized to the nanoparticle surface via EDC-NHS coupling. The fabrication of sensing platform for TBT can be divided into two steps that are the preparation of nanocomposite and the applying the nanocomposite onto nitrocellulose membrane. The selectivity constant and association kinetics were calculated to analyze the interaction of TBT with immobilized MINs. The results proved that the developed nanosensor is promising for the determination of TBT with high selectivity and sensitivity reaching a detection limit of 0.23 ppt in seawater. This novel photoluminescent nanosensor has the potential to pave the way for further studies and applications.

The authors describe a test stripe for fluorometric determination of the endocrine disruptor bisphenol A (BPA). Graphene quantum dots (GQDs) were immobilized on molecularly imprinted nanoparticles which then were placed on nitrocellulose paper. The GQDs display blue fluorescence (with excitation/emission peaks at 350/440 nm) which is reduced in the presence of BPA. The test stripe has a 43.9 ± 0.8 μg·L -1 limit of detection in case of water samples. The stripe was applied to the determination of BPA in (spiked) tap water and sea water, and the LODs were found to be 1.8 ± 0.2 μg·L -1 and 4.2 ± 0.5 μg·L -1 , respectively. Structural analogs of BPA, such as aminophenol, phenol, hydroquinone and naphthol were found not to interfere. Graphical abstract Schematic presentation of graphene quantum dots immobilized on molecularly imprinted nanoparticles placed on nitrocellulose paper for the determination of Bisphenol A in tap water and seawater. The method is based on the fluorescence quenching due to binding of targets in specific recognition sites.

The novel nanosensor based on Surface Plasmon Resonance (SPR) was developed for sensitive and selective detection of ciprofloxacin via molecularly imprinted nanoparticles (MIP/NPs). NPs were synthesized through miniemulsion polymerization technique with methacrylic acid as a functional monomer. FTIR, SEM, zetasizer and contact angle measurements were used for the characterization of MIP/NPs. After modification the SPR chip surface, the nanosensor was used for detection of ciprofloxacin in aqueous solution. According to selected concentration range, the correlation coefficient and limit of detections were obtained as 0.993 (R 2 ) and 3.21 and 7.1 ppb in ultrapure water and SWW, respectively. Association kinetic analysis, Scatchard, Freundlich, Langmuir and Freundlich-Langmuir isotherms were also performed on the data to investigate adsorption behaviour of ciprofloxacin on the surface of nanosensor. Tetracycline and enrofloxacin were used as competitor agents to examine the selectivity of nanosensor. Performance of the SPR nanosensor was also investigated by using synthetic wastewater (SWW) for detection of CPX. The reusability of nanosensor was investigated and good repeatability was obtained with 5.81% RSD. As a result, selective, simple and low-cost method to detect ciprofloxacin in aqueous solution was developed by combining MIP/NPs and SPR.

In this study, a new molecular imprinting (MIP)-based monolithic cryogel column was prepared using chemically crosslinked molecularly imprinted nanoparticles, to achieve a simplified chromatographic separation (SPE) for a model compound, L-glutamic acid (L-Glu). Cryogelation through crosslinking of imprinted nanoparticles forms stable monolithic cryogel columns. This technique reduces the leakage of nanoparticles and increases the surface area, while protecting the structural features of the cryogel for stable and efficient recognition of the template molecule. A non-imprinted monolithic cryogel column (NIP) was also prepared, using non-imprinted nanoparticles produced without the addition of L-Glu during polymerization. The molecularly imprinted monolithic cryogel column (MIP) indicates apparent recognition selectivity and a good adsorption capacity compared to the NIP. Also, we have achieved a significant increase in the adsorption capacity, using the advantage of high surface area of the nanoparticles.

The main objective of this study was to develop a novel surface plasmon resonance (SPR) nanosensor method based on a more rapid and selective determination of erythromycin (ERY) in the aqueous solution. This study is a combination of three techniques, which are miniemulsion polymerization, molecular imprinting and surface plasmon resonance techniques. In the first part, nanoparticles prepared with methacryl groups of functional monomer at surface acted as reactive sites for erythromycin as a template molecule. The molecularly imprinted nanoparticles were characterized by FTIR, SEM and zetasizer. After immobilization of nanoparticles on gold surface of SPR chip, nanosensor was characterized with contact angle measurements. This nanosensor was then used for selective determination of erythromycin. The linearity range and detection limit were obtained as 0.99 (r(2)) and 0.29 ppm, respectively. Association kinetic analysis, Scatchard, Langmuir, Freundlich and Freundlich-Langmuir isotherms were applied data. The selectivity of the SPR nanosensor was determined by using competitor agents (kanamycin sulfate, neomycin sulfate, spiramycin). The non-imprinted nanosensor was also used to evaluate the selectivity of ERY imprinted nanosensor. Finally, the nanosensor was tested for repeatability and it gave satisfactory response. These results demonstrate a method which is of low cost, rapid and provide reliable results in order to be used in detection of erythromycin from aqueous solution., (Copyright © 2015 Elsevier B.V. All rights reserved.)

In this study, we focused our attention on preparing of a new adsorbent for specific separation of immunoglobulin G (IgG). In this respect, we applied core-shell surface imprinting approach. Silica microspheres were selected as core-material to prepare specific surface imprinted polymer against IgG. Silica surface was activated via acidic treatment and modified with 3-methacryloyloxypropyl trimethoxysilane (MPTMS). Then, IgG molecules were imprinted on the surface of microspheres by using N-methacryloyl-L-aspartic acid as complexing/functional monomer. The core-shell silica microspheres were characterized using Fourier transform infrared spectroscopy, scanning electron microscopy, thermo gravimetric analysis and zeta size analysis. Then, the microspheres were used for the separation of IgG from aqueous solution to evaluate/optimize conditions. The effect of parameters such as concentration, pH, ionic strength, and temperature on the separation of IgG were evaluated in their relevant ranges. The maximum IgG adsorption capacities of IgG-imprinted and non-imprinted core-shell silica microspheres were found to be 15.43 and 9.43 mg/g, respectively, at pH 6.0 phosphate buffer. 1.0 M NaCl was used as a desorption agent. Selectivity of the imprinted microspheres was also investigated by using human serum albumin and haemoglobin as competitor molecules.

In this study, it was aimed to prepare hydrophobic cryogels for plasmid DNA (pDNA) purification from Escherichia coli lysate. The hydrophobicity was achieved by incorporating a hydrophobic ligand, N-methacryloyl-(L)-phenylalanine (MAPA), into the cryogel backbone. In addition to the conventional cryogelation process, freeze-drying step was included to create nanospines. Three different cryogels {poly(2-hydoxyethyl methacrylate-N-methacryloyl-L-phenylalanine)-freeze dried, [P(HEMA-MAPA)-FD]; poly(2-hydoxyethyl methacrylate-N-methacryloyl-L-phenylalanine, [P(HEMA-MAPA)] and poly(2-hydoxyethyl methacrylate)-freeze dried, [P(HEMA)-FD]} were prepared, characterized, and used for DNA (salmon sperm DNA) adsorption studies from aqueous solution. The specific surface areas of cryogels were determined to be 21.4 m(2)/g for P(HEMA)-FD, 17.65 m(2)/g for P(HEMA-MAPA) and 36.0 m(2)/g for P(HEMA-MAPA)-FD. The parameters affecting adsorption such as temperature, initial DNA concentration, salt type and concentration were examined in continuous mode. The maximum adsorption capacities were observed as 45.31 mg DNA/g, 27.08 mg DNA/g and 1.81 mg DNA/g for P(HEMA-MAPA)-FD, P(HEMA-MAPA) and P(HEMA)-FD, respectively. Desorption process was performed using acetate buffer (pH 5.50) without salt. First, pDNA was isolated from E. coli lysate and the purity of pDNA was then determined by agarose gel electrophoresis. Finally, the chromatographic performance of P(HEMA-MAPA)-FD cryogel for pDNA purification was tested in FPLC. The resolution (R(s)) was 2.84, and the specific selectivity for pDNA was 237.5-folds greater than all impurities., (Copyright © 2012 Elsevier B.V. All rights reserved.)