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The combination of magnetism and nanotechnology has presented promising materials: magnetic nanoparticles. These materials have been getting more attention due to their “size‐dependent functionality”. There is a critical size for nanoparticles that their properties change. Materials with various functions can be synthesized with the desired properties since a wide range of polymers including natural and synthetic polymers can be utilized in the production of the magnetic nanoparticles. Furthermore, they can be more selective and specific with the conjugation target-specific ligands. This structural and functional diversity enables these materials to be used in a wide range of areas. In this review, we discuss the main components of the magnetic nanoparticles and their examples in biomedical applications. They can be used as contrast agents in magnetic resonance imaging; delivery systems in the controlled release of therapeutic agents; supporting materials for separation, isolation, and purification of biomolecules. They can be also functioned in hyperthermia and magnetofection for gene therapy. However, even though their increasing research interest, magnetic nanoparticles still need to be improved to be more popular in the commercial area. We hope that these functional materials will present promising possibilities in nanotechnology and biomedicine in near future.

Plasmonic sensors based on the surface plasmon resonance (SPR) have shown prosperous growth in recent years due to their flexibility in designing it at smaller scale devices. The sensing techniques predominantly include surface-enhanced spectroscopic sensors such as surface-enhanced Raman scattering (SERS), surface-enhanced fluorescence (SEF) and surface-enhanced infrared absorption (SEIR), and SPR sensors which already have good commercial options. This chapter overviews and discusses the plasmonic nanosensors advancement and the most relevant applications in the field of agriculture. We focus on the effects that distinguish plasmonic nanosensors and give them their particular conduct for agrotechnology. We also evaluated the main applications of plasmonic nanosensors developed within the last five years for agriculture sector benefit.

A molecularly imprinted polymeric nanofilm was prepared for cocaine detection and applied to plasmonic nanosensor for real-time kinetic, selectivity and reusability analyses. The sensing polymeric surface was fabricated by synthesizing a selective and specific nanofilm on the gold plasmonic nanosensor surface. After characterization experiments with atomic force microscopy, ellipsometer, and contact angle measurements, the kinetic studies of cocaine detection in aqueous solutions in a wide concentration range between 0.2-100 μg/mL were applied to plasmonic nanosensor system at 24 °C with a low limit of detection (0.1 μg/L) and quantification values (0.3 μg/L) and the results showed that this molecularly imprinted polymeric nanofilm integrated plasmonic nanosensor is providing a model for the fastest, most accurate and most precise identification of the cocaine molecule which constitutes a large part of the workload of forensic laboratories.

The aim of this study is to prepare megaporous dye-affinity cryogel discs for the purification of plasmid DNA (pDNA) from bacterial lysate. Poly(hydroxyethyl methacrylate) [PHEMA] cryogel discs were produced by free radical polymerization initiated by N,N,N',N'-tetramethylene diamine (TEMED) and ammonium persulfate (APS) redox pair in an ice bath. Cibacron Blue F3GA was used as an affinity ligand (loading amount: 68.9μmol/g polymer). The amount of pDNA adsorbed onto the PHEMA-Cibacron Blue F3GA cryogel discs first increased and then reached a plateau value (i.e., 32.5mg/g cryogel) at 3.0mg/mL pDNA concentration. Compared with the PHEMA cryogel (0.11mg/g cryogel), the pDNA adsorption capacity of the PHEMA-Cibacron Blue F3GA cryogel (32.4mg/g polymer) was improved significantly due to the Cibacron Blue 3GA immobilization onto the polymeric matrix. pDNA adsorption amount decreased from 11.7mg/g to 1.1mg/g with the increasing of NaCl concentration. The maximum pDNA adsorption was achieved at 4°C. The overall recovery of pDNA was calculated as 90%. The PHEMA-Cibacron Blue F3GA cryogel discs could be used five times without decreasing the pDNA adsorption capacity significantly. The results show that the PHEMA-Cibacron Blue F3GA cryogel discs promise high selectivity for pDNA.

Poly-L-histidine immobilized poly(glycidyl methacrylate) (PGMA) cryogel discs were used for the removal of heavy metal ions [Pb(II), Cd(II), Zn(II) and Cu(II)] from aqueous solutions. In the first step, PGMA cryogel discs were synthesized using glycidyl methacrylate (GMA) as a basic monomer and methylene bisacrylamide (MBAAm) as a cross linker in order to introduce active epoxy groups through the polymeric backbone. Then, the metal chelating groups are incorporated to cryogel discs by immobilizing poly-L-histidine (mol wt ≥ 5000) having poly-imidazole ring. The swelling test, fourier transform infrared spectroscopy and scanning electron microscopy were performed to characterize both the PGMA and poly-L-histidine immobilized PGMA [P-His@PGMA] cryogel discs. The effects of the metal ion concentration and pH on the adsorption capacity were studied. These parameters were varied between 3.0–6.0 and 10–800 mg/L for pH and metal ion concentration, respectively. The maximum adsorption capacity of heavy metal ions...

WOS: 000394064800071, PubMed: 28183651, 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. (C) 2016 Elsevier B.V. All rights reserved., Ministry of Food, Agriculture and Livestock, of Republic of Turkey [TAGEM 12/AR-GE/35], This research has been carried out with supports from the Ministry of Food, Agriculture and Livestock, of Republic of Turkey with grant number TAGEM 12/AR-GE/35.

Supermacroporous cryogel with an average pore size of 10–200 μm in diameter was prepared by cryopolymerization of N-methacryloyl-( l )-glutamic acid (MAGA) and 2-hydroxyethyl methacrylate (HEMA). The poly(HEMA–MAGA) cryogel was characterized by surface area measurements, FTIR, swelling studies, elemental analysis and SEM. The poly(HEMA–MAGA) cryogel had a specific surface area of 23.2 m 2 /g. The equilibrium swelling ratio of the cryogel is 9.68 g H 2 O/g for poly(HEMA–MAGA) and 8.56 g H 2 O/g cryogel for PHEMA. The poly(HEMA–MAGA) cryogel disks with a pore volume of 71.6% containing 878 μmol MAGA/g were used in the removal of UO 2 2+ from aqueous solutions. Adsorption equilibrium of UO 2 2+ was obtained in about 30 min. The adsorption of UO 2 2+ ions onto the PHEMA cryogel disks was negligible (0.78 mg/g). The MAGA incorporation significantly increased the UO 2 2+ adsorption capacity (92.5 mg/g). The adsorption process is found to be a function of pH of the UO 2 2+ solution, with the optimum value being pH 6.0. Adsorption capacity of MAGA contained PHEMA based cryogel disks increased significantly with pH and then reached the maximum at pH 6.0. Consecutive adsorption and elution cycles showed the feasibility of repeated use for poly(HEMA–MAGA) cryogel disks.

Supermacroporous poly(2-hydroxyethyl methacrylate) (PHEMA) cryogel carrying DNA was used in the removal of anti-dsDNA antibodies from systemic lupus erythematosus (SLE) patient plasma. The PHEMA cryogel was prepared by bulk polymerization which proceeds in an aqueous solution of monomer frozen inside a plastic syringe. After thawing, the PHEMA cryogel contains a continuous matrix having interconnected macropores of 10–200 μm size. Pore volume in the PHEMA cryogel was 67.5%. Ester groups in the PHEMA structure were converted to imine groups by reacting with poly(ethyleneimine) (PEI) in the presence of NaHCO 3 . Amino (− NH 2 ) content of PEI-modified PHEMA cryogel was determined as 82 mg PEI/g. Then, DNA was attached onto the PHEMA cryogel via amino groups (53.4 mg DNA/g cryogel). Anti-dsDNA-antibody concentration declined significantly from 780 IU/ml to 80 IU/ml with the time. The maximum anti-dsDNA-antibody adsorption amount was 70 × 10 3 IU/g. Anti-dsDNA-antibodies could be repeatedly adsorbed and eluted without noticeable loss in the anti-dsDNA-antibody adsorption amount.

Poly(hydroxyethyl methacrylate) (PHEMA) nanobeads with an average size of 300 nm in diameter and with a polydispersity index of 1.156 were produced by a surfactant free emulsion polymerization. Specific surface area of the PHEMA nanobeads was found to be 996 m 2 /g. Imidazole containing 3-(2-imidazoline-1-yl)propyl(triethoxysilane) (IMEO) was used as a metal-chelating ligand. IMEO was covalently attached to the nanobeads. PHEMA-IMEO nanobeads were used for the removal of copper(II) ions from aqueous solutions. To evaluate the degree of IMEO loading, the PHEMA nanobeads were subjected to Si analysis by using flame atomizer atomic absorption spectrometer and it was estimated as 973 µmol IMEO/g of polymer. The PHEMA nanobeads were characterized by transmission electron microscopy and fourier transform infrared spectroscopy. Adsorption equilibrium was achieved in about 8 min. The adsorption of Cu 2+ ions onto the PHEMA nanobeads was negligible (0.2 mg/g). The IMEO attachment into the PHEMA nanobeads significantly increased the Cu 2+ adsorption capacity (58 mg/g). Adsorption capacity of the PHEMA-IMEO nanobeads increased significantly with increasing concentration. The adsorption of Cu 2+ ions increased with increasing pH and reached a plateau value at around pH 5.0. Competitive heavy metal adsorption from aqueous solutions containing Cu + , Cd 2+ , Pb 2+ and Hg 2+ was also investigated. The adsorption capacities are 61.4 mg/g (966.9 µmol/g) for Cu 2+ ; 180.5 mg/g (899.8 µmol/g) for Hg 2+ ; 34.9 mg/g (310.5 µmol/g) for Cd 2+ and 14.3 mg/g (69 µmol/g) for Pb 2+ . The affinity order in molar basis is observed as Cu 2+ > Hg 2+ > Cd 2+ > Pb 2+ . These results may be considered as an indication of higher specificity of the PHEMA-IMEO nanobeads for the Cu 2+ comparing to other ions. Consecutive adsorption and elution operations showed the feasibility of repeated use for PHEMA-IMEO nanobeads.

N-Methacryloyl-(L)-histidine methyl ester (MAH) was synthesized from metharyloyl chloride and histidine. Spherical beads with an average size of 150–250 μm were obtained by the suspension polymerization of ethylene glycol dimethacrylate and MAH in an aqueous dispersion medium. Magnetic poly(ethylene glycol dimethacrylate-co-N-Methacryloyl-(L)-histidine methyl ester) [m-p(EGDMA-co-MAH)] microbeads were characterized with swelling tests, electron spin resonance, elemental analysis, and scanning electron microscopy. The specific surface area of the beads was 80.1 m2/g. m-p(EGDMA-co-MAH) microbeads with a swelling ratio of 40.2% and 43.9 μmol of MAH/g were used for the adsorption of bovine serum albumin (BSA) in a batch system. The Cu(II) concentration was 4.1 μmol/g. The adsorption capacity of BSA on the Cu(II)-incorporated beads was 19.2 mg of BSA/g. The BSA adsorption first increased with the BSA concentration and then reached a plateau, which was about 19.2 mg of BSA/g. The maximum adsorption was observed at pH 5.0, which was the isoelectric point of BSA. The BSA adsorption increased with decreasing temperature, and the maximum adsorption was achieved at 4°C. High desorption ratios (>90% of the adsorbed BSA) were achieved with 1.0M NaSCN (pH 8.0) in 30 min. The nonspecific adsorption of BSA onto the m-p(EGDMA-co-MAH) beads was negligible. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 2669–2677, 2004

The selective binding of albumin on dye-affinity nanospheres was combined with magnetic properties as an alternative approach for albumin depletion from human plasma. Magnetic poly(hydroxyethyl methacrylate) (mPHEMA) nanospheres were synthesized using mini-emulsion polymerization method in the presence of magnetite powder. The specific surface area of the mPHEMA nanospheres was found to be 1302 m2/g. Subsequent to Cibacron Blue F3GA (CB) immobilization onto mPHEMA nanospheres, a serial characterization processing was implemented. The quantity of immobilized CB was calculated as 800 μmol/g. Ultimately, albumin adsorption performance of the CB-attached mPHEMA nanospheres from both aqueous dissolving medium and human plasma were explored.

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.