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Current practices in synthesizing molecularly imprinted polymers face challenges-lengthy process, low-productivity, the need for expensive and sophisticated equipment, and they cannot be controlled in situ synthesis. Herein, we present a micro-reactor for in situ and continuously synthesizing trillions of molecularly imprinted polymeric nanoparticles that contain molecular fingerprints of bovine serum albumin in a short period of time (5-30 min). Initially, we performed COMSOL simulation to analyze mixing efficiency with altering flow rates, and experimentally validated the platform for synthesizing nanoparticles with sizes ranging from 52-106 nm. Molecular interactions between monomers and protein were also examined by molecular docking and dynamics simulations. Afterwards, we benchmarked the micro-reactor parameters through dispersity and concentration of molecularly imprinted polymers using principal component analysis. Sensing assets of molecularly imprinted polymers were examined on a metamaterial sensor, resulting in 81% of precision with high selectivity (4.5 times), and three cycles of consecutive use. Overall, our micro-reactor stood out for its high productivity (48-288 times improvement in assay-time and 2 times improvement in reagent volume), enabling to produce 1.4-1.5 times more MIPs at one-single step, and continuous production compared to conventional strategy., (© 2023. Springer Nature Limited.)

In this study, we designed a surface plasmon resonance (SPR) biosensors based on molecular imprinting to detect low amounts of thrombin directly in a short time, both in thrombin aqueous solutions and in patient serum samples. For this purpose, the thrombin imprinted and non-imprinted SPR biosensors were prepared by integrating the synthesized thrombin imprinted and non-imprinted nanoparticles on the allyl mercaptan modified gold SPR chip surface. The kinetic studies were performed with a thrombin concentration range from 0.1 to 400 pM with a detection limit of approximately 0.017 pM in thrombin aqueous solution. Morever, the limit of detection was found to be 0.033 pM in patient serum samples. When the selectivity of the thrombin imprinted SPR biosensors was compared with the competing molecules as bovine serum albumin and lysozyme, it was showed that the thrombin was 4.58 times and 3.99 times more selective than the bovine serum albumin and lysozyme molecules, respectively. The shelf life and reusability of the designed SPR biosensor showed that there was a 12.93% decrease in the performance according to the kinetic analyzes that performed after 8 months. In addition, thrombin detection from the patient serum samples was performed using both SPR biosensor and the enzyme-linked immunosorbent assay methods, and were calculated recoveries., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Hemoglobin (Hb) is the most abundant protein in the blood. It is vital for the living as oxygen carriers. Some of the very pure Hb-containing biological fluids are currently under clinical trial. However, the removal and purification of Hb from the blood are quite difficult, especially when it is at a low concentration level. In this study, the molecularly imprinted polymeric nanoparticles (MIPNs) were prepared using N-methacryloyl-histidine methyl ester (MAH) by mini-emulsion polymerization technique for specific binding of human hemoglobin (HHb). MIPNs in monosize form have a size of 152 ± 4 nm. They also have a high binding capacity (32.33 mg/g) of HHb. MIPNs retain 84% of the re-binding capacity for HHb after 10 cycles. The nanoparticles have 16 and 5 times higher binding capacity of HHb, respectively, in the presence of bovine serum albumin and lysozyme. Thanks to their high binding capacity and selectivity, MIPNs will allow them to be detected selectively for different target molecules. According to molecular docking, the main binding forces depend on hydrogen bonds and Van der Waals forces in the interaction within 5 Å around MAH molecule are observed through the amino acid residues of HHb at β1 and β2 subunit. The statistical mechanical analysis of docking showed that the free energy (ΔG) is -2732.14 kcal/mol, which indicates the interaction between MAH and HHb is energetically favorable at 298.15°K., (© 2021 John Wiley & Sons Ltd.)

Human serum albumin (HSA) is a major blood plasma protein also found in urine where its existence may be a marker of some types of liver or kidney dysfunction. Herein, we fabricated a novel surface plasmon resonance (SPR) nanosensor for selective, sensitive, and label-free microalbumin detection both in aqueous and urine sample solutions. First, HSA-imprinted nanoparticles were synthesized, which consist of ethylene glycol dimethacrylate and N-methacryloyl-L-leucine methyl ester as a cross-linker and functional monomer. The nanoparticles were characterized by zeta-size and scanning electron microscope analyses and were dropped onto the SPR chip surface to make HSA sensitive nanosensor. Characterization studies of HSA-imprinted SPR chip were carried out by atomic force microscopy, Fourier-transform infrared spectroscopy, contact angle, and ellipsometer. The limit of detection and limit of quantification values of HSA-imprinted SPR nanosensor were calculated as 0.7 pM and 1.9 pM for the concentration range of 0.15-500 nM. Selectivity studies of HSA-imprinted SPR nanosensor were achieved with hemoglobin and transferrin proteins which were chosen as competitor molecules. HSA-imprinted SPR nanosensor was displayed highly selective and sensitive to HSA.

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.

Boronate affinity chromatography is a common purification method used for isolation and purification of cis-diol containing biomolecules. Poly (hydroxyethyl methacrylate-co-vinyl phenyl boronic acid) [P(HEMA-VPBA)] nanoparticles were prepared by miniemulsion polymerization to use in RNA purification methods. The P(HEMA-VPBA) nanoparticles were characterized by particle size distribution, surface area, Fourier transform infrared spectroscopy and atomic force microscopy. The effects of temperature, pH, RNA concentration and different salt types on RNA binding on the P(HEMA-VPBA) nanoparticles were examined. It was observed that RNA binding was increased with the increasing of pH and max RNA binding was obtained at pH 9.0. RNA binding capacity of the P(HEMA-VPBA) nanoparticles was increased from 167mg/g to 601mg/g with addition of BaCl 2 to the binding medium. Maximum RNA binding capacity of the P(HEMA-VPBA) nanoparticles was 172mg/g at 1.0mg/mL initial RNA concentration. The P(HEMA-VPBA) nanoparticles were reusable for RNA binding. RNA was also extracted from Escherichia coli cells and purified successfully using the P(HEMA-VPBA) nanoparticles., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Diagnostic biomarkers such as proteins and enzymes are generally hard to detect because of the low abundance in biological fluids. To solve this problem, the advantages of surface plasmon resonance (SPR) and nanomaterial technologies have been combined. The SPR sensors are easy to prepare, no requirement of labelling and can be detected in real time. In addition, they have high specificity and sensitivity with low cost. The nanomaterials have also crucial functions such as efficiency improvement, selectivity, and sensitivity of the detection systems. In this report, an SPR-based sensor is developed to detect lysozyme with hydrophobic poly (N-methacryloyl-(L)-phenylalanine) (PMAPA) nanoparticles. The SPR sensor was first characterized by attenuated total reflection-Fourier transform infrared, atomic force microscope, and water contact angle measurements and performed with aqueous lysozyme solutions. Various concentrations of lysozyme solution were used to calculate kinetic and affinity coefficients. The equilibrium and adsorption isotherm models of interactions between lysozyme solutions and SPR sensor were determined and the maximum reflection, association, and dissociation constants were calculated by Langmuir model as 4.87, 0.019 nM -1 , and 54 nM, respectively. The selectivity studies of SPR sensor were investigated with competitive agents, hemoglobin, and myoglobin. Also, the SPR sensor was used four times in adsorption/desorption/recovery cycles and results showed that, the combination of optical SPR sensor with hydrophobic ionizable PMAPA nanoparticles in one mode enabled the detection of lysozyme molecule with high accuracy, good sensivity, real-time, label-free, and a low-detection limit of 0.66 nM from lysozyme solutions. Lysozyme detection in a real sample was performed by using chicken egg white to evaluate interfering molecules present in the medium., (Copyright © 2017 John Wiley & Sons, Ltd.)

This study reports a surface plasmon resonance (SPR) based affinity sensor system with the use of molecular imprinted nanoparticles (plastic antibodies) to enhance the pesticide detection. Molecular imprinting based affinity sensor is prepared by the attachment of atrazine (chosen as model pesticide) imprinted nanoparticles onto the gold surface of SPR chip. Recognition element of the affinity sensor is polymerizable form of aspartic acid. The imprinted nanoparticles were characterized via FTIR and zeta-sizer measurements. SPR sensors are characterized with atomic force microscopy (AFM), scanning electron microscopy (SEM), Fourier transform infrared spectrophotometry (FTIR) and contact angle measurements. The imprinted nanoparticles showed more sensitivity to atrazine than the non-imprinted ones. Different concentrations of atrazine solutions are applied to SPR system to determine the adsorption kinetics. Langmuir adsorption model is found as the most suitable model for this affinity nanosensor system. In order to show the selectivity of the atrazine-imprinted nanoparticles, competitive adsorption of atrazine, simazine and amitrole is investigated. The results showed that the imprinted nanosensor has high selectivity and sensitivity for atrazine., (Copyright © 2016 Elsevier B.V. All rights reserved.)

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.

Molecular imprinting is a polymerization technique that provides synthetic analogs for template molecules. Molecularly imprinted polymers (MIPs) have gained much attention due to their unique properties such as selectivity and specificity for target molecules. In this study, we focused on the development of polymeric materials with molecular recognition ability, so molecular imprinting was combined with miniemulsion polymerization to synthesize self-orienting nanoparticles through the use of an epitope imprinting approach. Thus, L-lysine imprinted nanoparticles (LMIP) were synthesized via miniemulsion polymerization technique. Immunoglobulin G (IgG) was then bound to the cavities that specifically formed for L-lysine molecules that are typically found at the C-terminus of the Fc region of antibody molecules. The resulting nanoparticles makes it possible to minimize the nonspecific interaction between monomer and template molecules. In addition, the orientation of the entire IgG molecule was controlled, and random imprinting of the IgG was prevented. The optimum conditions were determined for IgG recognition using the imprinted nanoparticles. The selectivity of the nanoparticles against IgG molecules was also evaluated using albumin and hemoglobin as competitor molecules. In order to show the self-orientation capability of imprinted nanoparticles, human serum albumin (HSA) adsorption onto both the plain nanoparticles and immobilized nanoparticles by anti-human serum albumin antibody (anti-HSA antibody) was also carried out. Due to anti-HSA antibody immobilization on the imprinted nanoparticles, the adsorption capability of nanoparticles against HSA molecules vigorously enhanced. It is proved that the oriented immobilization of antibodies was appropriately succeeded., (Copyright © 2014 Elsevier B.V. All rights reserved.)

The aim of this study is to prepare silanized polymeric nanoparticles for DNA isolation. Polymeric p(HEMA)-IMEO-PBA nanoparticles around 85.7 nm diameter, was obtained by surfactant free emulsion polymerization for DNA isolation. Synthesized nanoparticles for characterization studies were realized scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and Zeta-size. Surface area, average particle size and size distribution were also performed. The surface area of synthesized silanized polymeric nanoparticles was 2460 m(2)/g. Synthesized polymeric nanoparticles were silanized with 3-(2-imidazoline-1-yl)propyl (triethoxysilane) (IMEO). After that, phenylboronic acid (PBA) which is DNA specific ligand were covalently binded to silanized polymeric nanoparticles. The amount of DNA adsorbed onto the p(HEMA)-IMEO-PBA nanoparticles first increased and then reached a saturation value at around 14.0 mg/mL of DNA concentration. The maximum adsorption was 672.41 mg/g silanized polymeric nanoparticles in the optimum adsorption medium. The maximum DNA adsorption was achieved at 4°C. The overall recovery of DNA was calculated as 95%. In repetitive adsorption-desorption circles, it is observed not being important decrease in DNA adsorption capacities. The results were shown that silanized polymeric nanoparticles can be a good alternative for DNA isolation., (Copyright © 2013 Elsevier B.V. All rights reserved.)

In this study, lanthanide ion complex incorporated molecularly imprinted fluorescent nanoparticles were synthesized. A combination of three novel approaches was applied for the purpose. First, lanthanide ions [Terbium(III)] were complexed with N-methacryloyl-L-histidine (MAH), polymerizable derivative of L-histidine amino acid, in order to incorporate the complex directly into the polymeric backbone. At the second stage, L-histidine molecules imprinted nanoparticles were utilized instead of whole protein imprinting in order to avoid whole drawbacks such as fragility, complexity, denaturation tendency, and conformation dependency. At the third stage following the first two steps mentioned above, imprinted L-histidine was coordinated with cupric ions [Cu(II)] to conduct the study under mild conditions. Then, molecularly imprinted fluorescent nanoparticles synthesized were used for L-histidine adsorption from aqueous solution to optimize conditions for adsorption and fluorimetric detection. Finally, usability of nanoparticles was investigated for chiral biorecognition using stereoisomer, D-histidine, racemic mixture, D,L-histidine, proteins with surface L-histidine residue, lysozyme, cytochrome C, or without ribonuclease A. The results revealed that the proposed polymerization strategy could make significant contribution to the solution of chronic problems of fluorescent component introduction into polymers. Additionally, the fluorescent nanoparticles reported here could be used for selective separation and fluorescent monitoring purposes., (Copyright © 2013 Elsevier B.V. All rights reserved.)

Poly(2-hydroxyethyl methacrylate)/3-(2-imidazoline-1-yl)propyl(triethoxysilane) (PHEMA/IMEO) nanoparticles were attached on surface plasmon resonance (SPR) sensor for the real-time detection of human immunoglobulin G (IgG) in human serum. The PHEMA/IMEO nanoparticles-attached SPR sensor was characterized by Fourier transform infrared spectroscopy (FTIR), atomic force microscopy (AFM), and contact angle measurements. IgG detection studies were performed using aqueous IgG solutions at different concentrations. In order to show the selectivity and specificity of the SPR sensor, competitive kinetic analyses were performed using IgG, albumin, hemoglobin in singular and competitive manner. Finally, IgG detection in human serum was carried out.

α-Amylase (EC 3.2.1.1; α-D-1,4,glucan glucanohydrolase) catalyzes the hydrolysis of α-D-(1,4)-glucosidic linkages in starch, glycogen, and various malto-oligosaccharides, by releasing α-anomeric products. In this study, a novel method has been developed to prepare nanoprotein particles that carry α-amylase as a monomer by using a photosensitive microemulsion polymerization process. The nanostructured α-amylase with photosensitive features have been characterized by fluorescence spectroscopy, transmission electron microscopy (TEM) and Zeta Sizer. The fluorescence intensity of amylase nanoparticles was determined to be 658 a.u. at 610 nm and the average particle size of nanoamylase was found to be about 71.8 nm. Both free α-amylase and nanoparticles were used in the hydrolysis of starch under varying reaction conditions such as pH and temperature that affect enzyme activity and the results were compared to each other. Km values were 0.26 and 0.87 mM and Vmax values were 0.36 IU mg(-1) and 22.32 IU mg(-1) for nanoenzyme and free enzyme, respectively. Then, thermal stability, storage stability and reusability were investigated and according to the results, activity was preserved 60% at 60 °C; 20% at 70-80 °C temperature values and 80% after 105 days storage. Finally after 10 cycles, the activity was preserved 90% and this novel enzymatic polymeric amylase nanoparticle has showed considerable potential as reusable catalyst., (Copyright © 2012 Elsevier B.V. All rights reserved.)

The aim of this study is to label the cells with polymeric nanoparticles properly and efficiently. For this purpose, acridine orange (AO)-loaded poly(2-hydroxyethyl methacrylate) (PHEMA) nanoparticles were synthesized by miniemulsion polymerization. PHEMA nanoparticles were characterized by zeta sizer, zeta potential, atomic force microscopy (AFM), scanning electron microscopy (SEM), transmission electron microscopy (TEM), fluorescence microscopy, Fourier transform infrared spectrophotometer (FTIR), and elemental analysis. In addition, the toxicity of the nanoparticles were investigated by MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay.

Immobilized metal ion affinity chromatography (IMAC) is a useful method for adsorption of proteins that have an affinity for transition metal ions. In this study, poly(hydroxyethyl methacrylate-methacryloyl-L-tryptophan) (PHEMATrp) nanoparticles were prepared by surfactant free emulsion polymerization. Then, Cu(II) ions were chelated on the PHEMATrp nanoparticles to be used in lysozyme adsorption studies in batch system. The maximum lysozyme adsorption capacity of the PHEMATrp nanoparticles was found to be 326.9 mg/g polymer at pH 7.0. The nonspecific lysozyme adsorption onto the PHEMA nanoparticles was negligible. In terms of protein desorption, it was observed that adsorbed lysozyme was readily desorbed in medium containing 1.0 M NaCl. The results showed that the metal-chelated PHEMATrp nanoparticles can be considered as a good adsorbent for lysozyme purification., (Copyright © 2012 Elsevier B.V. All rights reserved.)

The purification of immunoglobulin G (IgG) from human plasma was performed by using a novel metal-chelated adsorbent with nano size. The non-porous nanoparticles were produced by surfactant free emulsion polymerization of ethylene glycol dimethacrylate (EDMA) and 2-methacryloylamidohistidine (MAH). Then, Cu(II) ions were chelated on the nanoparticles. The nano-poly(EDMA-MAH) nanoparticles were characterized by Fourier transform infrared, scanning electron microscope, atomic force microscope and elemental analysis. The non-porous nanoparticles were spherical form and have 100-250 nm size distribution. The maximum IgG adsorption capacity of the Cu(II) chelated nanoparticles was found to be 463 mg/g polymer at pH 7.0 in HEPES buffer. Desorption of IgG was performed by 1.0 M NaCl and desorption rate was found to be 97 %. IgG was obtained from human plasma with purity of 94 % (up to 578 mg/g polymer). The non-porous nanoparticles allowed one-step purification of IgG from human plasma.

The aim of this study is to prepare quartz crystal microbalance (QCM) nanosensor for the real-time detection of lysozyme. In the first part, the lysozyme imprinted (MIP) nanoparticles were prepared by mini-emulsion polymerization. The MIP nanoparticles were characterized by TEM, zeta-sizer and FTIR-ATR measurements. Particle size was found around 50 nm. The MIP nanoparticles were attached by dropping of nanoparticle solution to gold surface and then, dried at 37°C for 6h. QCM nanosensor was characterized with AFM and ellipsometer. The observations indicated that the nanoparticle film was almost monolayer. The detection limit was found as 1.2 ng/mL. The specificity of the QCM nanosensor was shown by using albumin as a competitor molecule. The results show that the QCM nanosensor has high selectivity and sensitivity with a wide range of lysozyme concentrations in both aqueous solutions (0.2-1500 μg/mL) and natural sources (egg white) (460-1500 ng/mL)., (Copyright © 2010 Elsevier B.V. All rights reserved.)

Poly(hydroxyethyl methacrylate) (PHEMA) nanoparticles with an average size of 300 nm in diameter and with a polydispersity index of 1.156 were produced by surfactant free emulsion polymerization. Specific surface area of the PHEMA nanoparticles was found to be 996 m(2)/g. Metal-chelating ligand 3-(2-imidazoline-1-yl)propyl(triethoxysilane) (IMEO) was covalently attached to the PHEMA nanoparticles. IMEO content was 0.97 mmol IEMO/g. The morphology and properties of these nanoparticles were characterized with scanning electron microscopy, Fourier transform infrared spectroscopy and atomic force microscopy. The Cu2+-chelated PHEMA-IMEO nanoparticles were used in the adsorption-elution studies of human serum albumin (HSA) in a batch system. Maximum HSA adsorption amount of the Cu2+ chelated nanoparticles was 680 mg HSA/g. The PHEMA-IMEO-Cu2+ nanoparticles exhibited a quite high adsorption capacity and fast adsorption rate due to their high specific surface area and the absence of internal diffusion resistance.

Poly(hydroxyethyl methacrylate) (PHEMA) nanoparticles with an average size of 150 nm in diameter and with a poly-dispersity index of 1.171 were produced by a surfactant free emulsion polymerization. Specific surface area of the PHEMA nanoparticles was found to be 1779 m(2)/g. Reactive imidazole containing 3-(2-imidazoline-1-yl)propyl(triethoxysilane) (IMEO) was used as a pseudo-specific ligand. IMEO was attached covalently onto the nanoparticles. PHEMA-IMEO nanoparticles were used for the affinity binding of immunoglobulin-G (IgG) from human plasma. To evaluate the degree of IMEO loading, the PHEMA nanoparticles were subjected to Si analysis by using flame atomizer atomic absorption spectrometer and it was estimated as 64.5 mg/g of polymer. The nanoparticles were characterized by transmission electron microscopy (TEM) and Fourier transform infrared spectroscopy (FTIR). IgG binding onto the PHEMA nanoparticles was found to be 5.2 mg/g. Much higher binding values (up to 843 mg/g) were obtained for the PHEMA-IMEO nanoparticles. IgG could be repeatedly bound and eluted on PHEMA-IMEO nanoparticles without noticeable loss in the IgG binding capacity.

The aim of this study is the synthesis of nanoparticles with selective arsenic recognition capability for the removal of arsenic from water. Arsenic recognition based molecularly imprinted (As(V)-MIP) were synthesized using the molecular imprinting technique via mini-emulsion polymerization. The synthesized As(V)-MIP nanoparticles were characterized using zeta sizer, zeta potential, FTIR, Raman spectroscopy, scanning electron microscopy (SEM), atomic force microscopy (AFM), and elemental analysis. The adsorption behavior of nanoparticles was investigated in a batch system at pH 4.0–9.0. The maximum adsorption capacity of As(V)-MIP nanoparticles was determined to be 54.29 mg As/g polymer at pH 5.0. Various parameters such as pH, concentration and adsorption time were examined to determine the optimum adsorption conditions. As(V)-MIP nanoparticle selectivity experiments were conducted in the presence of NO3−, PO43−, and SO42− anions to determine the relative selectivity coefficients (K'). The experimental data showed a good correlation with the Langmuir isotherm equation and adherence of the adsorption process to pseudo-second-order kinetics was observed. Applying As(V)-MIP nanoparticles to real water sample showed up to 95.3% As(V) removal efficiency. Reusability experiments were performed by renewal of nanoparticles using a 1 M HNO3 solution containing 0.05% thiourea. [ABSTRACT FROM AUTHOR]

Estradiol, a phenolic steroid oestrogen, is one of the endocrine-disrupting chemicals (EDCs) found in natural and tap waters. The detection and removal of EDCs is attracting attention daily as they negatively affect animals' and humans' endocrine functions and physiological conditions. Therefore, developing a fast and practical method for the selective removal of EDCs from waters is essential. In this study, we prepared 17β-estradiol (E2)-imprinted HEMA-based nanoparticles onto bacterial cellulose nanofibres (E2-NP/BC-NFs) to use for the removal of E2 from wastewater. FT-IR and NMR confirmed the structure of the functional monomer. The composite system was characterised by BET, SEM, µCT, contact angle, and swelling tests. Additionally, the non-imprinted bacterial cellulose nanofibres (NIP/BC-NFs) were prepared to compare the results of E2-NP/BC-NFs. Adsorption of E2 from aqueous solutions was performed in batch mode and investigated via several parameters for optimisation conditions. The effect of pH studies was examined in the 4.0–8.0 range using acetate and phosphate buffers and a concentration of E2 of 0.5 mg/mL. The maximum E2 adsorption amount was 254 µg/g phosphate buffer at 45 °C. The experimental data show that the Langmuir is a relevant isotherm model for E2 adsorption. Additionally, the relevant kinetic model was the pseudo-second-order kinetic model. It was observed that the adsorption process reached equilibrium in less than 20 min. The E2 adsorption decreased with the increase in salt at varying salt concentrations. The selectivity studies were performed using cholesterol and stigmasterol as competing steroids. The results show that E2 is 46.0 times more selective than cholesterol and 21.0 times more selective than stigmasterol. According to the results, the relative selectivity coefficients for E2/cholesterol and E2/stigmasterol were 8.38 and 86.6 times greater for E2-NP/BC-NFs than for E2-NP/BC-NFs, respectively. The synthesised composite systems were repeated ten times to assess the reusability of E2-NP/BC-NFs. [ABSTRACT FROM AUTHOR]

In the study, magnetic poly(hydroxyethylmethacrylate-N-methacryloyl-(L)-histidine) (mPHEMAH) nanoparticles were prepared by miniemulsion polymerisation using N-methacryloyl-(L)-histidinemethylester as basic monomer. The specific surface area of the magnetic nanoparticles was found to be 1050 m2/g. Maximum Protein C adsorption capacites of the Ni(II), Cu(II) and Zn(II) ions chelated magnetic poly(hydroxyethyl methacrylate-N-methacryloyl-(L)-histidine) nanoparticles were calculated as 589.22, 436.33 and 388.15 mg/g nanoparticles, respectively. This work was focused on the purity of the Protein C by sodium dodecyl sulphate polyacrylamide gel electrophoresis yielding a satisfactory result of 92% purity. Thе rеusаbilitys of thе Ni(II)-mPHEMAH, Cu(II)-mPHEMAH and Zn(II)-mPHEMAH nanoparticles were аpproximаtеly 93.5%, 94% and 95% respectively. [ABSTRACT FROM AUTHOR]

This research describes the design and determination of the biomimetic biosensor used for histamine detection in cheese and canned tuna samples. Histamine imprinted nanoparticles (MIP) were synthesized and characterized by scanning electron microscopy, and size analysis. After, histamine imprinted nanoparticles were coated onto an SPR chip surface. The modified chips were characterized by using contact angle, atomic force microscopy, ellipsometry, and scanning electron microscopy. The optic analysis by the SPR biosensor has been implemented with a PBS solution of pH 7.4. The novel biosensor shows high sensitivity, low detection limit (0.58 ng.mL−1) and a wide linear range from 0.001 to 10 μg.mL−1. The histamine imprinted biosensor was successfully analyzed on spiked food samples. The simple procedure, easy preparation, and low production cost provide that sensors coated with biomimetic nanoparticles to be attractive for sensitive and selective detection of targets. [ABSTRACT FROM AUTHOR]

Human serum albumin (HSA) is a major blood plasma protein also found in urine where its existence may be a marker of some types of liver or kidney dysfunction. Herein, we fabricated a novel surface plasmon resonance (SPR) nanosensor for selective, sensitive, and label-free microalbumin detection both in aqueous and urine sample solutions. First, HSA-imprinted nanoparticles were synthesized, which consist of ethylene glycol dimethacrylate and N-methacryloyl-L-leucine methyl ester as a cross-linker and functional monomer. The nanoparticles were characterized by zeta-size and scanning electron microscope analyses and were dropped onto the SPR chip surface to make HSA sensitive nanosensor. Characterization studies of HSA-imprinted SPR chip were carried out by atomic force microscopy, Fourier-transform infrared spectroscopy, contact angle, and ellipsometer. The limit of detection and limit of quantification values of HSA-imprinted SPR nanosensor were calculated as 0.7 pM and 1.9 pM for the concentration range of 0.15–500 nM. Selectivity studies of HSA-imprinted SPR nanosensor were achieved with hemoglobin and transferrin proteins which were chosen as competitor molecules. HSA-imprinted SPR nanosensor was displayed highly selective and sensitive to HSA. [ABSTRACT FROM AUTHOR]

Controlled drug delivery system is a technique which has considerable recent potential in the fields of pharmacy and medicine. Mitomycin C is commonly used drug in the treatment of superficial bladder and breast cancers. In the present study, mitomycin C-imprinted magnetic poly(hydroxyethyl methacrylate)-based nanoparticles (MIMNs) were prepared using surfactant free emulsion polymerization for controlled delivery of mitomycin C. The MIMNs were characterized by fourier transform infrared spectroscopy, scanning electron microscopy, atomic force microscopy, electron spin resonance, and elemental analysis. The average particle diameter of MIMNs was about 200 nm. [ABSTRACT FROM AUTHOR]

In this work, Reactive Blue 15 dye functionalized poly(HEMA) nanoparticles were synthesized for reversible adsorption of lysozyme from its aqueous solution. For this, nano-sized poly(HEMA) nanoparticles were synthesized by the surfactant free emulsion polymerization. Reactive Blue 15 dye then covalently attached to the polymeric structure. These novel dye attached poly(HEMA) nanoparticles were used for the adsorption of lysozyme. Characterization of dye attached nanoparticles was carried out by using FTIR, AFM, and elemental analysis. Incorporation of the dye onto the polymeric structure was demonstrated by FTIR and elemental analysis, while the size and the shape of the nanoparticles were shown by AFM. The incorporated amount of the dye was found to be 70.3 μmol/g nanoparticle with sulphur stoichiometry and it was found that the prepared nanoparticles were in a spherical form and were about 100 nm diameter. Lysozyme adsorption studies were carried out with different conditions (pH, lysozyme concentration, temperature, and ionic strength) and maximum lysozyme adsorption was found to be 630.7 mg/g nanoparticle at pH 7.0 in 25°C medium temperature. Adsorbed lysozyme was desorbed by 1.0 M of NaCl with 96% recovery and synthesized dye-attached nanoparticles were used 10 times without any decrease in their adsorption capacity. [ABSTRACT FROM AUTHOR]

The main problem in cancer chemotherapy is the cytotoxic side effects of therapeutics on healthy tissues and cells. The targeted drug delivery and nanotechnology are intensively investigated area to find new ways to solve, at least to reduce, these problems. Hereby, we have reported a new method inspired from both conventional military strategies and biorecognition in the body. In this respect, we have produced two fluorescent nano-drug systems with bitargeting and biorecognition properties, recognizing cancer cells and each other. The multiplexed nanostructures were interacted with HL-60 cells to show their efficiency for bitargeting, ambushing, timed, and double-controlled cancer cell apoptosis. [ABSTRACT FROM AUTHOR]

The focus of this article is to develop a surface plasmon resonance (SPR) nanosensor to determine chloramphenicol (CAP) using the molecularly imprinted nanoparticles. The CAP imprinted nanoparticles were prepared by miniemulsion polymerization method. Then, the nanoparticles were attached onto the SPR nanosensor surface via temperature-controlled evaporation. Surface characterization studies were performed with atomic force microscopy and contact angle measurements. Kinetic studies were performed with CAP solutions in the concentration range of 0.155-6.192 n M. Florphenicol (FLP) and thiamphenicol (TAP) having similar chemical structures to the template (i.e., CAP) were chosen as competitors to determine selectivity of the nanoparticles. Selectivity constants were observed as 8.86 for CAP/TAP and 8.36 for CAP/FLP. The detection limit was calculated as 40 ng/kg honey sample. In the light of these results, it was emphasized that the SPR nanosensor is able to recognize CAP selectively and has a potential for real-time CAP detection in honey sample. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 [ABSTRACT FROM AUTHOR]

Novel magnetic nanoparticles with an average size of 350-400 nm with N-methacryloyl-( L)-phenylalanine (MAPA) as a hydrophobic monomer were prepared by the surfactant-free emulsion polymerization of 2-hydroxyethyl methacrylate, MAPA, and magnetite in an aqueous dispersion medium. MAPA was synthesized from methacryloyl chloride and L-phenylalanine methyl ester. The specific surface area of the nonporous magnetic nanoparticles was found to be 580 m2/g. Magnetic poly[2-hydroxyethyl methacrylate- N-methacryloyl-( L)-phenylalanine] nanoparticles were characterized by Fourier transform infrared spectroscopy, electron spin resonance, atomic force microscopy, and transmission electron microscopy. Elemental analysis of MAPA for nitrogen was estimated as 4.3 × 10−3 mmol/g of nanoparticles. Then, magnetic nano-poly[2-hydroxyethyl methacrylate- N-methacryloyl-( L)-phenylalanine] nanoparticles were used in the adsorption of Bacillus licheniformis α-amylase in a batch system. With an optimized adsorption protocol, a very high loading of 705 mg of enzyme/g nanoparticles was obtained. The adsorption phenomena appeared to follow a typical Langmuir isotherm. The inverse of enzyme affinity for free amylase (181.82 mg/mL) was higher than that for immobilized enzyme (81.97 mg/mL). Storage stability was found to increase with adsorption. It was observed that the enzyme could be repeatedly adsorbed and desorbed without a significant loss in the adsorption amount or enzyme activity. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 [ABSTRACT FROM AUTHOR]

• Three SPR sensors were prepared for sensitive recognition of Cd(II) ions. • SPR sensor is stable and repeatable with 0.01 µg/mL limit of detection value. • Sensitive detection methods were developed for wastewater control. • Sensor is stable with rapid response time at room temperature. This study reports a sensitive sensor-based measurement technique for selective and sensitive detection of Cd(II) ions at low concentrations using ion-imprinted technology. Heavy metal pollution is an extremely hot topic on scientific research for several decades. Cd(II) is one of the most toxic and carcinogenic heavy metals. The limit of concentration of Cd(II) ions allowed to be found in the drinking water and industrial wastewater has been defined as 3 µg/L by the World Health Organization. Therefore, a simple, reliable and effective method is required for the determination of Cd(II) ions. Surface plasmon resonance sensor is the most commonly used optical sensors due to their unique ability for real-time monitoring the molecular binding events. We have proposed a sensitive experimental platform capable of achieving detection in 6–7 min. In this work, the benefits of three different approaches were compared according to their performance enhancement effects on sensors. Poly(hydroxyethyl methacrylate) thin-film, polymeric nanoparticles, and gold nanoparticles were separately used for designing sensors surface for the sensitive detection of Cd(II) ions. Combination of the signal enhancing properties of nanoparticles and ion-imprinting technique provided sensitive and selective detection with a comparatively low limit of detection value to the SPR sensor system. The limit of detection value has been defined as 0.01 µg/L for selective Cd(II) ions detection which is less than the value determined by the World Health Organization. The real time detection of Cd(II) ions from wastewater solutions (SPS Quality Control Material Waste Water Level 2) was also carried out by the SPR sensors. [ABSTRACT FROM AUTHOR]

Abstract: Molecular imprinted polymers (MIPs) as a recognition element for sensors are increasingly of interest and MIP-nanoparticles have started to appear in the literature. In this study, we have proposed a novel thiol ligand-capping method with polymerizable methacryloylamido-cysteine (MAC) attached to gold nanoparticles, reminiscent of a self-assembled monolayer and have reconstructed surface shell by synthetic host polymers based on molecular imprinting method for recognition. In this method, methacryloylamidohistidine-Pt(II) [MAH-Pt(II)] has used as a new metal-chelating monomer via metal coordination–chelation interactions and cholic acid. Nanoshell sensors with templates give a cavity that is selective for cholic acid. The cholic acid can simultaneously chelate to Pt(II) metal ion and fit into the shape-selective cavity. Thus, the interaction between Pt(II) ion and free coordination spheres has an effect on the binding ability of the gold nanoparticles nanosensor. The binding affinity of the cholic acid imprinted nanoparticles has investigated by using the Langmuir and Scatchard methods and determined affinity constant (K affinity) were found as 1.48×104molL−1 and 6.59×106molL−1, respectively. At the last step of this procedure, cholic acid level in blood serum and urine which belong to healthy people was determined by the prepared Au nanosensor. [Copyright &y& Elsevier]

Abstract Human fecal contamination poses a crucial environmental and health threat in recent years, resulting in the difficulties of access to clean water. According to the World Health Organization, several fecal bacteria, particularly Enterococci species, are present in human intestinal flora. Enterococcus faecalis (E. faecalis) is one of the indicator bacteria that have been utilized as a pollution indicator in water. However, existing technologies and detection strategies face multiple challenges in terms of low affinity for detection and labelling requirements that limit their access to large scale applications. Here, we present a label-free molecular fingerprinting strategy on a plasmonic sensor to detect E. fecalis from aqueous and seawater samples. The kinetic performance of platform was comprehensively evaluated and the platform provided four orders of magnitude detection range with a low limit of detection (down to ~100 bacteria/mL) and a high correlation coefficient value (> 0.99) in the range of 2 × 104–1 × 108 cfu/mL. The platform also denoted a selectivity and specificity while other bacteria (E. coli , B. subtilis , and S. aureus) samples were applied. Multiple time use and relatively long shelf-life are superior to the existing modality. The presented method is one of the fascinating surface modification technique that utilizes biotarget as a recognition element itself, providing a broad range of versatility to replica other biotargets with different molecular structure, size, and physicochemical properties. Such a reliable and versatile platform would hold potential applications from microbiome characterization to forensics by revitalizing obsolescent detection strategies. Highlights • A plasmonic sensor was prepared for real-time E. faecalis detection using molecularly imprinted nanoparticles. • The kinetic, selectivity and repeatability analyses were evaluated by employing the E. faecalis-imprinted plasmonic sensor. • The plasmonic sensor can detect E. faecalis with a low limit of detection and a high correlation coefficient values. [ABSTRACT FROM AUTHOR]

Profiling at GCs level is an important issue since it is a key factor to determine administration intent for either therapeutic or doping purpose. In this study, the sensing platform which is based on a combination of surface plasmon resonance system with molecularly imprinted nanoparticles was developed for monitoring of prednisolone level as a selected GCs analyte in plasma and urine. Fabricated sensing platform was utilized with ellipsometer and contact angle measurements followed by characterization of nanoparticles (NPs) by the means of structurally (i.e. FTIR and elemental analysis) and morphologically (i.e. TEM and Zeta-sizer analysis). The lowest limit of detection by PIN2 encoded molecularly imprinted nanoparticle was achieved as at 5.5 ppb and 8.9 ppb at pH 6.6 and 7.4, respectively. Competition kinetic assays were performed by using 17-α-ethynyl estradiol (EEST) and estradiol (EST). The reusability studies have been applied to the sensor with the best results and 92.8% recovery is achieved. Validation studies of the system were performed according to the standard procedure by high performance liquid chromatography (HPLC). The method was successfully applied to monitor PRD levels in body fluids (urine and plasma) as a natural sample. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Abstract: In this study, we have prepared lysozyme imprinted poly(ethylene glycol dimethacrylate-N-methacryloyl-l-histidine methylester) (PEDMAH) nanoparticles and then attached on the surface of surface plasmon resonance (SPR) sensor. Lysozyme imprinted SPR nanosensor was characterized by Fourier transform infrared spectroscopy, atomic force microscopy, and ellipsometry. The nanosensor has an ability to detect lysozyme molecules from both aqueous and natural complex source, chicken egg white, even if it has lysozyme concentration as low as 32.2nM. Association kinetics analysis, Scatchard, Langmuir, Freundlich, Langmuir–Freundlich isotherms were applied to data. The calculated detection limit, association and dissociation constants are 84pM, 108.71nM−1 and 9.20pM, respectively. The non-imprinted nanosensors were also prepared to evaluate the selectivity of the imprinted nanosensor. Finally, the nanosensor is used for five adsorption–desorption–regeneration cycle and it gives reproducible response. [Copyright &y& Elsevier]

Abstract: Novel magnetic nanospheres with an average size of 118nm utilizing N-methacryloyl-(l)-cysteine methyl ester (MAC) as a monomer were prepared by surfactant free emulsion polymerization of 2-hydroxyethyl methacrylate (HEMA) and MAC conducted in an aqueous dispersion medium. MAC was synthesized using methacryloyl chloride and l-cysteine methyl ester. l-Cysteine groups of the mag-poly(HEMA–MAC) nanospheres were chelated with Fe3+ ions. Specific surface area of the nonporous nanospheres was found to be 2452m2/g. Mag-poly(HEMA–MAC)-Fe3+ nanospheres contained 0.81mmolsulphur/g polymer were used in the adsorption of catalase in batch system. Using an optimized adsorption protocol, a very high loading of 820mg catalase/g nanosphere was obtained. The adsorption phenomena appeared to follow a typical Langmuir isotherm. The immobilized catalase has more resistence to temperature inactivation than that of their free form. The optimum pH value of catalase was not affected by the immobilization reaction, but the pH profile was broadened for the immobilized enzyme. Kinetic parameters were determined for immobilized catalase as well as for the free enzyme. The values of the Michaelis constant K m of catalase were significantly smaller (ca. 2.5 times) upon immobilization, indicating increased affinity of the enzyme for its substrate, whereas V max value of free catalase was higher than that of the immobilized enzyme. It was also observed that enzyme could be repeatedly adsorbed and desorbed on the mag-poly(HEMA–MAC)-Fe3+ nanospheres without loss of adsorption capacity or enzymatic activity. [Copyright &y& Elsevier]

Abstract: Poly(hydroxyethyl methacrylate-N-methacryloly-(l)-histidinemethylester) [PHEMAH] nanospheres with an average size of 158.2nm were prepared by surfactant free emulsion polymerization conducted in an aqueous dispersion medium. MAH was synthesized using methacryloyl chloride and l-histidine methyl ester. Then, Cu(II) ions were attached as a metal ligand because of its affinity towards proteins. Specific surface area of the PHEMAH nanospheres was calculated to be 1454m2/g. The PHEMAH nanospheres were characterized by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). Average particle size, size distribution, and surface charge measurements were also performed. Elemental analysis of MAH for nitrogen was estimated as 0.42mmol/g nanosphere. Then, PHEMAH-Cu2+ nanospheres were used for laccase adsorption in a batch system. The maximum laccase adsorption was observed at pH 6.0. Laccase could be repeatedly adsorbed and desorbed with PHEMAH-Cu2+ nanospheres without noticeable loss in the adsorption capacity. [Copyright &y& Elsevier]

Abstract: Molecular imprinted polymers (MIPs) as a recognition element for sensors are increasingly of interest and MIP nanoparticles have started to appear in the literature. In this study, we have proposed a novel thiol ligand-capping method with polymerizable methacryloylamido-cysteine (MAC) attached to CdS quantum dots (QDs), reminiscent of a self-assembled monolayer and have reconstructed surface shell by synthetic host polymers based on molecular imprinting method for DNA recognition. In this method, methacryloylamidohistidine-platinium (MAH-Pt(II)) is used as a new metal-chelating monomer via metal coordination-chelation interactions and guanosine templates of DNA. Nanoshell sensors with guanosine templates give a cavity that is selective for guanosine and its analogues. The guanosine can simultaneously chelate to Pt(II) metal ion and fit into the shape-selective cavity. Thus, the interaction between Pt(II) ion and free coordination spheres has an effect on the binding ability of the CdS QD nanosensor. The binding affinity of the guanosine imprinted nanocrystals has investigated by using the Langmuir and Scatchard methods, and experiments have shown the shape-selective cavity formation with O6 and N7 of a guanosine nucleotide (K a =4.841×106 molL−1) and a free guanine base (K a =0.894×106 molL−1). Additionally, the guanosine template of the nanocrystals is more favored for single stranded DNA compared to double stranded DNA. [Copyright &y& Elsevier]

• QCM chip coated with nanoparticles was sensitive to recognition elements. • Nanosensor is highly selective and sensitive to SCs in presence of different compounds in saliva. • Nanosensor is stable and repeatable with rapid response time at room temperature. • The sensing mechanism of nanosensor towards SCs was proposed as hydrophobic interaction. Synthetic cannabinoids (SCs), which are becoming increasingly popular, are an important public health issue considering the common abuse uses and serious adverse effects associated with intoxication. The analysis for controlling the increase in synthetic cannabinoids usage requires a faster and highly sensitive detection that rapidly developing class compounds. In this study, a piezoelectric nanosensor coated with a synthetic biomimetic recognition nanoparticles polymer was designed for the real-time and highly sensitive synthetic cannabinoids (SCs: JWH-018, JWH-073, JWH-018 pentanoic acid and JWH-073 butanoic acid) detection. Synthetic cannabinoids imprinted (MIP) and non-imprinted (NIP) nanoparticles were synthesized. Firstly, the characterization of MIP and NIP nanoparticles were studied by FTIR-ATR, scanning electron microscope, and size measurements. After, nanoparticles were spread onto a quartz crystal microbalance (QCM) chip. Different QCM chip surfaces were studied by contact angle, ellipsometry, and atomic force microscopy measurements. Selective rebinding of target analytes was monitored as a frequency shift measuring mass change with the QCM. Limit of detection values were calculated as 0.28, 0.3, 0.23, 0.29 pg/mL for these SCs in artificial saliva, respectively. The SCs-MIP QCM nanosensors displayed high sensitivity and selectivity in a wide concentration range of SCs (0.0005–1.0 ng/mL) in artificial saliva. Image, graphical abstract [ABSTRACT FROM AUTHOR]