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In this work, microscale poly-2-hydroxyethyl methacrylate [p(HEMA)]-based cryogels were fabricated as a drug delivery material using molecular imprinting technology for controlled release of mitomycin C (MMC) as an anti-cancer drug. MMC imprinted pHEMA-based micro cryogels (pMIPs) were prepared according to free-radical polymerization by using N-methacryloyl-(l)-histidine methyl ester (MAH) as an amino-acid-based polymerizable functional monomer using a micro stencil array chip with microwells of 200 μm diameter and 500 μm thickness. Following that, scanning electron microscope, swelling test, and Fourier Transform Infrared Spectroscopy were used for the characterization studies of pMIPs. After the characterization studies, MMC release performance of pMIPs was investigated towards the different pH values and various MMC concentrations in the aqueous solutions. The in vitro cytotoxicity studies of the pMIPs and the non-imprinted pHEMA based micro cryogels (pNIPs) were examined using L929 cell line. According to the experimental findings, the incorporation of MAH monomer could increase the release performance of pMIPs and the release of MMC from the pMIPs was non-Fickian in the aqueous solution. pMIPs did not show any noticeable cytotoxicity and could be potentially used as a new drug carrier for MMC release.

In this work, the usability of magnetic gelatin nanofiber (MGNF) for anionic dye removal was investigated in the aqueous solution. For this aim, the MGNF was prepared using the electrospinning technique with the addition of Fe3O4 nanopowders. After the characterization of MGNF with Fourier transform infrared spectroscopy, swelling test, scanning electron microscope, and energy-dispersive X-ray analysis, the adsorption performance of MGNF against the dye molecule, Orange G, was examined by changing the pH of the media, the dye concentration, and the ionic strength. The experimental results showed that the maximum adsorbed amount of Orange G was found as 15.6 mg/g at pH 3 value and the Orange G adsorption behavior was endothermic, physical, and suited to the Langmuir adsorption isotherm model. The adsorption kinetic of Orange G was evaluated with the pseudo-first-order, the pseudo-second-order, and the Elovich kinetic models and the pseudo-second-order model results fitted the experimental findings as compared to the other models. The affordable magnetic adsorbent was capable of maintaining its stability after five consecutive adsorption, desorption, and regeneration cycles without significant loss of adsorption capacity.

In this work, a surface plasmon resonance (SPR) based immunosensor was prepared by the immobilization of the amine-functionalized gold nanoparticles (N-AuNPs) on the sensing surface to sense immunoglobulin M (IgM) antibodies in the aqueous solution and artificial plasma. The characterization studies of SPR based immunosensor for IgM detection were performed with scanning electron microscope (SEM), contact angle measurements, and ellipsometry. Kinetic studies for the IgM immunosensor were carried out in the range of 1.0 to 200 ng/mL IgM concentrations in an aqueous solution. The total IgM analysis time including adsorption, desorption, and regeneration cycles was nearly 10 min for the prepared immunosensor. The limit of detection (LOD) and limit of quantification (LOQ) were found as 0.08 and 0.26 ng/mL, respectively. The reusability of the proposed immunosensor was tested with 6 consecutive adsorption-desorption, and regeneration cycles. Also, enzyme-linked immunosorbent assay (ELISA) method was utilized in the validation of the immunosensor.

Metal ions play a pivotal role in biological process, which act as an actor to protect the stabilities of enzymes and proteins and help to carry out their functionalities with permissible limits, however, some metal ions such as cadmium, arsenic can lead to enzyme inhibition, induce the oxidative stress and unwanted conditions like the impairment of mismatch mechanism. Hence, the monitoring of metal ions including trace metals is great importance not only living beings but maintain the ecosystem also. Currently available methods for determination of metal ions include inductively coupled plasma mass spectrometry (ICP-MS), atomic absorption spectrometry (AAS), and high-performance liquid chromatography (HPLC). While these chromatographic and analytical methods offer high sensitivity and selectivity, these costly instruments require intense technical training because of their time consuming and complicated procedures. In recent years, sensors have several advantages over other analytical methods. Sensors are more preferred compared to analytical methods and have attractive increasing attention because of their high sensitivity, low cost, fast response, portability, simple operation, and on-site operation. In this chapter, we first summarized the importance of metal ions for life-balance for biological processes, after the commonly used methods for detection of metal ions including sensor platforms were discussed with the latest research articles by the combining of molecular imprinting technology.

*Topçu, Aykut Arif ( Aksaray, Yazar ), Human immunoglobulin M (hIgM) antibodies are considered as hopeful tools for diseases therapy. Therefore, chromatography approaches are used to purify hIgM with a single step. In this study, we prepared a poly(hydroxyethyl methacrylate) based immunoaffinity p(HEMA-I) cryogel column by using cyanamide to immobilize antihuman immunoglobulin on the p(HEMA) cryogel for purification of hIgM in aqueous solution and artificial human plasma. The characterization of the p(HEMA) cryogel column was performed by using a scanning electron microscope (SEM), micro-computerized tomography (µ-CT), Fourier transform infrared spectroscopy (FTIR), swelling degree and macro-porosity. Further, the optimizations of various parameters were performed such as, pH, ionic strength, temperature and concentration of hIgM in aqueous solutions. In addition, the Langmuir adsorption model was supported by experimental results. Maximum adsorbed amount of hIgM corresponded to 11.1 mg/g at pH 5.75 [morpholino ethanesulfonic acid (MES buffer)]. Our results indicated that the p(HEMA-I) cryogel column can be reused at least 10 times without significant loss in adsorption capacity. As a natural source, artificial human plasma was selected for hIgM adsorption and the purity of hIgM was evaluated using sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). © 2020 by the authors. Licensee MDPI, Basel, Switzerland.

Creatinine imprinted cryogel (MIP) cartridge was prepared with functional monomer N-methacryloyl-(L)-histidinemethylester (MAH) under frozen conditions. Creatinine adsorption studies and selectivity of MIP cryogel were evaluated in aqueous solution and artificial urine sample. Maximum adsorbed amount of creatinine was calculated as 6.83 mg/g polymer for MIP cryogel. Langmuir and Freundlich adsorption isotherm models were used to investigate the adsorption behaviour of creatinine. In the artificial urine sample; recovery amounts of creatinine were found 34.7–46.2%. Creatinine imprinted cryogel (MIP) cartridge recognized creatinine, 4.58 and 4.37 times greater competitive molecules. MIP cryogel catridge was repeatedly used many times for adsorption desorption cycles. © 2017 Taylor & Francis Group, LLC.

WOS: 000399567500002, PubMed: 28105892, In this study, cryogel-based implantable molecularly imprinted drug delivery systems were designed for the delivery of antineoplastic agent. Mitomycin C imprinted poly(2-hydroxyethyl methacrylate-N-methacryloyl-l-glutamic acid) cryogel membranes were produced by free-radical bulk polymerization under partially frozen conditions. The membranes were characterized by swelling tests, Fourier transform infrared spectroscopy, scanning electron microscopy, surface area measurements and in vitro hemocompatibility tests. In vitro delivery studies were carried out to examine the effects of cross-linker ratio and template content. Mitomycin C imprinted cryogel membranes have megaporous structure (10-100 mu m in diameter). The cumulative release of mitomycin C was decreased with increasing cross-linking agent ratio and increased with the amount of template in the cryogel structure. The nature of transport mechanism of the mitomycin C from the membranes was non-Fickian., TUBITAK-BIDEB2211-National Ph.D. Scholarship Programme, Kemal Cetin thanks The Scientific and Technological Research Council of Turkey (TUBITAK) for the support by 'TUBITAK-BIDEB2211-National Ph.D. Scholarship Programme'.

Increasing of the world population and food demand has led to the development of new agricultural practices to improve food production using more effective pesticides. The controlled release formulations of pesticides are used to delay the release of the biologically active components into their environment for a defined period of time. In these formulations, compounds are incorporated in a polymer matrix by different chemical or physical incorporation techniques. Reducing the toxicity of the compounds and unwanted side effects on non-target organisms are prominent characteristics of these formulations. The development of an ideal controlled release pesticide formulation is just as difficult as developing the ideal pesticide. For these reasons, further research works are needed. In this chapter, the recent applications of sensor systems to detect pesticides in environmental studies with particular attention to the fate of pesticides once introduced in water and soil, and also the advantages of their use are discussed. Current trends in the development of sensor technology for rapid assessment of the environment, as well as challenges for practical implementation and future research directions, are discussed. Findings show that the use of sensors to detect pesticides can improve the quality of the environment and help detect polluted sites.

WOS: 000471359400002, Molecular imprinting technique is used to design artificial creatinine receptor on the gold surface of surface plasmon resonance (SPR) chip using N-methacryloyl-(L)-histidine methyl ester (MAH), as a functional monomer. Surface characterization of SPR sensor chip is performed with atomic force microscope (AFM), ellipsometry and contact angle measurements. Creatinine imprinted SPR sensor is characterized with a linear range between 1 and 100 mM and limit of detection (LOD) and limit of quantification (LOQ) of creatinine are found 57 mu M and 190 mu M, respectively. N-hydroxysuccinimide (NHS) and creatine molecules are selected to examine the selectivity of creatinine imprinted SPR sensor. Reusability studies of SPR sensor is determined in urine mimic samples., Republic of Turkey, Ministry of Science, Industry and Technology [0505_TGSD.2015_2], This study was funded and supported by Republic of Turkey, Ministry of Science, Industry and Technology (Grand No. 0505_TGSD.2015_2).

Topçu, Aykut Arif ( Aksaray, Yazar ) Yılmaz, Erkut ( Aksaray, Yazar ), Tailor-made Escherichia coli (E. coli) receptors were created with microcontact imprinted technique and binding events of E. coli were carried out by a surface plasmon resonance (SPR) sensor in aqueous solution and in urine mimic in real time and label-free. N-methacryloyl-(L)-histidine methyl ester (MAH) was selected as a functional monomer to design tailor-made E. coli receptors on the polymeric film and during the formation of the polymeric film on a chip surface, Ag nanoparticles (AgNPs) were entrapped into the polymer mixture in order to lower the detection limit of biomimetic SPR based sensor. The polymeric film was characterized with atomic force microscopy (AFM), scanning electron microscopy (SEM), ellipsometer and contact angle measurements. Limit of detection (LOD) was found 0.57 CFU/mL and feasibility of the biomimetic sensor was investigated in urine mimic.

TOPCU, Aykut Arif/0000-0002-5434-4920; Doker, Serhat/0000-0002-4694-1960 WOS: 000349806600013 Herein, we have reported particle-assisted ion-imprinted cryogels, which were synthesized by embedding finely crushed functional particles into cryogel structure under semifrozen conditions. These cryogels showed high adsorption efficiency and affinity against Cd-II ions. CdII adsorption performances were evaluated by varying some effective factors. In order to analyze the data, we applied Langmuir and Freundlich adsorption isotherms while using three different kinetic models, pseudo-first-order, pseudo-second-order, and WeberMorris as well. Also, the dimensionless equilibrium parameter (R-L), initial adsorption rate, and half-adsorption time were calculated. The results revealed that ion-imprinted-polymer (IIP) cryogels have homogeneously distributed cavities, which were formed by a particle-assisted imprinting process, and the theoretical maximum adsorption capacity (Q(max), 35.97 mu g/g) was very close to the experimental value (Q(eq), 32.15 mu g/g). In addition, R-L values for both IIP and nonimprinted-polymer cryogels showed favorability of the adsorption process, while kinetic models indicated that there were no diffusion limitations during the adsorption process, which means that the rate-limiting step was chemosorption of heavy-metal ions on binding sites (imprinted cavities or functional groups) with a high initial adsorption rate and a low half-adsorption time. Desorption, reusability, and selectivity studies were also conducted to state the performance of the cryogels. In conclusion, this promising approach provides a novel methodology for selective Cd-II removal from water sources. Scientific and Technological Research Council of TurkeyTurkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [2209] L.U. warmly thanks to Prof. Dr. Adil Denizli for his valuable discussion and sharing facilities. B.T. thanks to The Scientific and Technological Research Council of Turkey for their financial support under Program 2209, Research Fellowship Programme for Undergraduate Students.

DNA isolation/purification is a widely used procedure for molecular biology, medical studies, gene therapy and especially PCR studies which needs high quality or extremely pure nucleic acid samples. Nucleic acid separation was mainly achieved by two methods; solvent extraction and solid phase extraction SPE methods. Although solvent extraction method is the simplest method, there are some drawbacks such as toxicity, more solvent requirement, time-consuming procedure and low specificity. Nowadays, there is a wide use of solid phase matrices to extract DNA from a variety of samples. In this review article; we basically focused on SPE for DNA purification methods., D NA’nın saflaştırılması veya izole edilmesi moleküler biyoloji, tıbbi çalışmalar ve gen tedavi çalışmaları için önem taşır. Özellikle PCR çalışmaları için yüksek saflıkta DNA molekülüne ihtiyaç duyulmaktadır. Nükleik asitlerin saflaştırılmasında sırasıyla çözücü özütlemesi ve katı faz özütlemesi olmak üzere iki yöntem kulanılır. Çözücü ekstraksiyonu kolay uygulanabilir olmasına rağmen; toksisite, yüksek oranda çözücü ihtiyacı, yöntemin uzun zaman alması ve düşük özgüllüğü gibi birtakım kısıtlamalar mecvuttur. Günümüzde çeşitli örneklerden DNA’nın saflaştırılması için katı faz özütlemesi SPE yaygın olarak kullanılmaktadır. Bu çalışmada; özellikle DNA’nın saflaştırılması için SPE yönteminin uygulamaları üzerinde durulmuş ve bilimsel çalışmalar özetlenmiştir