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Cryogels are defined as polymeric gel matrices with interconnected macropores providing an advantage to be efficient carriers enabling unhindered diffusion of interested molecule. Cryogels could be easily prepared with the combination of molecular imprinting. Molecular imprinting technology provides selective and sensitive recognition for biomolecules. Immunoglobulin G (IgG) is a main effector component in human response. It is recently well recognized that the purification strategies for IgG have intensively gained attention to treat immune defects. Several methods including affinity chromatography have been applied for the purification of IgG from complex media. The purification of IgG plays a crucial role in medical applications using several materials. Among these, cryogels have been widely applied for the purification of several biomolecules. They offer to create low-cost affinity systems with high chemical and physical stability. Above all, temperature sensitive polymers enable a reversible phase transition against small temperature changes, by the way, reversible swelling and shrinking manner is observed.In this chapter, immunoglobulin G imprinted thermosensitive poly(N-isopropylacrylamide-N methacryloyl-(l)-histidine) [p(NIPA-MAH)/IgG-MIP] monolithic cryogel is explained. The preparation and characterization of cryogels are summarized. In addition, IgG binding studies with different parameters are briefly described. Herein, an effective design principle is presented to create imprinted temperature-sensitive cryogels for IgG purification. A p(NIPA-MAH)/IgG-MIP monolithic cryogel was synthesized for IgG purification. Afterward, IgG binding capacity of p(NIPA-MAH)/IgG-MIP cryogels was examined in different experimental conditions. Apart from these, selectivity of the p(NIPA-MAH)/IgG-MIP cryogel was shown by comparing IgG binding capacity of nonimprinted [p(NIPA-MAH)/NIP] one. Finally, the IgG purification ability of the p(NIPA-MAH)/IgG-MIP cryogel from human plasma was demonstrated proving its application in affinity chromatography using real sample.

Ochratoxin A (OTA), a group of highly toxic fungal secondary metabolites, is one of the most common mycotoxins that contaminate a wide range of agricultural products. Herein, we designed a label-free and selective surface plasmon resonance (SPR) based sensor for detection of OTA contamination in dried fig. The molecularly imprinted polymer film (MIP) was fabricated onto the SPR sensor chip by using light-initiated polymerization of N-methacryloyl-(L)-phenylalanine and 2-Hydroxyethyl methacrylate in the presence of OTA as a template. SPR chips were characterized by using contact angle, atomic force microscopy, and ellipsometry. OTA imprinted sensor was displayed a broad linear range, between 0.1 ng/mL and 20 ng/mL. The limit of detection was calculated as 0.028 ng/mL. The selectivity studies of the OTA imprinted SPR sensor was performed in the presence of aflatoxin M1, aflatoxin B1, and citrinin. The imprinting factor was found to be 2.85. The adsorption behavior of the OTA imprinted sensor was found as suitable for the Langmuir model. Results displayed that the OTA imprinted SPR sensor was successfully applied to determine OTA in dried fig samples.

In this work, it was aimed to purify peroxidase from Brassica oleracea roots using newly synthesized cryogel membranes. 2-4-vinylphenylboronic acid (VPBA) containing 2-hydroxyethyl methacrylate (HEMA) [PHEMABA] cryogel membranes were prepared successfully and swelling tests, scanning electron microscopy (SEM), Fourier-transform infrared (FTIR) spectroscopy, contact angle measurements, and Brauner-Emmet-Teller (BET) surface area analysis were done for characterization. Effect of experimental conditions on peroxidase binding capacity of PHEMABA cryogel membranes was determined by examining parameters such as pH, temperature and time with binding studies. Maximum peroxidase binding capacity of PHEMABA cryogel membranes was determined as 22.01 mg/g for 2 mg/mL equilibrium peroxidase concentration at pH 8.0. Finally, peroxidase was purified from Brassica oleracea roots with 85.38% yield and 18.38 purification fold. According to obtained results, spongy PHEMABA cryogel membranes show high peroxidase binding capacity and could be suggested as a boronate affinity model system for enzyme purification.

In this study, selective and sensitive detection of the neurotransmitter dopamine (DA) in both aqueous solution and biological samples was performed using a surface plasmon resonance (SPR) sensor based on a molecular imprinting technique. For this, dopamine-imprinted poly(2-hydroxyethyl methacrylate-N-methacroyl-(L)-cysteine methyl ester-gold nanoparticles-N-methacryloyl-L-phenylalanine methyl ester) [PHEMAC-AuNPs/MAPADA] nanoparticles were prepared. Furthermore, to evaluate the imprinting efficiency, non-imprinted [PHEMAC-AuNPs/MAPA] nanoparticles were designed using the same polymerization procedure except for the addition of dopamine molecules. To examine the effect of incorporating AuNPs to increase the SPR signal response, control experiments were carried out via the SPR biosensor produced using [PHEMAC/MAPADA] nanoparticles prepared without the addition of AuNPs. Characterization studies of dopamine- + imprinted [PHEMAC-AuNPs/MAPADA] and non-imprinted [PHEMAC-AuNPs/MAPA] nanoparticles was performed with a zetasizer and an FTIR-ATR spectrophotometer. In addition, dopamine-imprinted [PHEMAC-AuNPs/MAPADA] and non-imprinted [PHEMAC-AuNPs/MAPADA] SPR sensors were characterized by ellipsometer and contact angle measurements. The high imprinting efficiency (I.F: 9.67) of the dopamine-imprinted [PHEMAC-AuNPs/MAPADA] SPR sensor was determined by comparing it with the non-imprinted [PHEMAC-AuNPs/MAPA] SPR sensor. A good linear relationship was obtained in the 0.01–0.5 ppb concentration range with correlation coefficients of 0.9818 and 0.9819, respectively. The dopamine-imprinted [PHEMAC-AuNPs/MAPADA] SPR sensor was 5.53 and 4.59 times more selective for the target molecule dopamine than for epinephrine (EP) and norepinephrine (NE), respectively. The repeatability of the [PHEMAC-AuNPs/MAPADA] SPR sensor was assessed with a 0.5 ppb dopamine solution, with the percent relative standard deviation of the intra-assays (RSD) being less than 1.7%, indicating negligible loss of dopamine sensing capability after four adsorption–desorption cycles with the same sensor.

In this study, surface plasmon resonance (SPR) and quartz crystal microbalance (QCM) sensors were prepared for the detection of amoxicillin from the commercial and local chicken eggs by using molecular imprinting technique. Amoxicillin imprinted poly(hydroxyethyl methacrylate-methacrylic acid) polymeric film was synthesized onto the surface of the SPR and QCM chips by ultra violet polymerization to determine lower concentrations of amoxicillin. Ellipsometry, contact angle analysis, and atomic force microscopy measurements were used for the surface morphology of the polymeric film layer. The ellipsometric thickness of AMOX imprinted and nonimprinted SPR and QCM chip surfaces were measured as 35 ± 0.9 nm, 32.89 ± 1.9 nm, 30 ± 0.6 nm, and 28 ± 0.22 nm, respectively. Contact angles of bare gold surfaces, AMOX imprinted SPR and QCM chip surfaces were measured to be as 82.3° ± 0.15, 79.2° ± 0.14, 75.01° ± 1.07, and 69.11° ± 0.89, respectively. The range of linearity was measured as 0.1 to 10 ng/mL for amoxicillin imprinted SPR and QCM sensors. The maximum residue limit of AMOX in eggs is at 10 µg/kg in accordance with the "Positive List System for Agricultural Chemical Residues in Foods." The response time for the test, including adsorption, desorption, and regeneration, was approximately 45 min. The limit of detections for SPR and QCM sensors were found to be 0.0005 and 0.0023 ng/mL, respectively. The reusabilities of amoxicillin imprinted SPR and QCM sensors were observed by the equilibration-binding-regeneration. Validation studies of the AMOX imprinted SPR and QCM sensors were performed by liquid chromatography-tandem mass spectrometry.

The term biomimetic can be simply defined as the examination of nature. The scientists inspired by the enormous diversity of nature to solve human problems or facilitate daily life by mimicking natural models, systems, and elements especially in the biomedical and therapeutic applications to make better drugs, artificial organs, sensing instruments, etc. Biological recognition elements like proteins, antibodies, enzymes, DNA, lectins, aptamers, cells, and viruses have been heavily used to ensure specificity in such applications in spite of their lack of stability and reusability. However, in the last two decades molecularly imprinted polymers, MIPs, have been synthesized as an alternative to mimic natural biological interactions for a broad spectrum of templates by means of coordinating functional monomers around template in the presence of cross-linker. This review will outline the broad contours of biomimetics prepared by molecular imprinting techniques and their practical applications in the separation techniques, tissue engineering applications, biomimetic surfaces, sensors, artificial membranes, and drug delivery systems.

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.

Applications of nanomaterials to biological systems have received increased interest in the past decades. In particular, bacterial cellulose nanofibers can be utilized in a broad range of applications. Biomaterials have been produced on large-scale with high reproducibility by an inspiring method such as molecular imprinting. Herein, for the first time, magnetic bacterial cellulose nanofibers are designed by the molecular imprinting method as a novel adsorbent for selective and efficient recognition of thymidine nucleoside. In this process, magnetic bacterial cellulose nanofibers are silanized with 3-(trimethoxysilyl) propyl methacrylate and further polymerized with a hydrophilic monomer for templating thymidine via metal chelate coordination. They are characterized by several methods and then applied for thymidine recognition to optimize the adsorption conditions. Hereby, the effecting factors are evaluated, and the highest adsorption capacity is obtained as 431.3 mg/g in pH 9.0 at 25 °C. The selectivity is assessed with competitor nucleosides and highly selective (4.13 and 3.80 times) adsorption of thymidine at the same concentration of other nucleosides (cytidine and uridine) is observed. After multiple adsorption–desorption experiments, the magnetic bacterial cellulose nanofibers also provided high reusability capacity. The present new work holds excellent potential for nucleoside recognition by integrating molecular imprinting with magnetic bacterial cellulose nanofibers.

Molecularly imprinted cryogels for protein recognition have received much attention in recent years with the development of supermacroporous polymer systems. Molecularly imprinted cryogels, which o...

Introduction: A molecular imprinting is one of the fascinating modification methods that employ molecules as targets to create geometric cavities for recognition of targets in the polymeric matrix. This method provides a broad versatility to imprint target molecules with different size, three-dimensional structure and physicochemical features. In contrast to the complex and timeconsuming laboratory surface modification procedures, this method offers a rapid, sensitive, inexpensive, easy-to-use, and selective approach for the diagnosis, screening and monitoring disorders. Owing to their unique features such as high selectivity, physical and chemical robustness, high stability, low-cost and reusability of this method, molecularly imprinted polymers have become very attractive materials and been applied in various applications from separation to detection. Background: The aims of this review are structured according to the fundamentals of molecularly imprinted polymers involving essential elements, preparation procedures and also the analytical applications platforms. Finally, the future perspectives to increase the development of molecularly imprinted platforms. Methods: A molecular imprinting is one of the commonly used modification methods that apply target as a recognition element itself and provide a wide range of versatility to replica other targets with a different structure, size, and physicochemical features. A rapid, easy, cheap and specific recognition approach has become one of the investigation areas on, especially biochemistry, biomedicine and biotechnology. In recent years, several technologies of molecular imprinting method have gained prompt development according to continuous use and improvement of traditional polymerization techniques. Results: The molecularly imprinted polymers with excellent performances have been prepared and also more exciting and universal applications have been recognized. In contrast to the conventional methods, the imprinted systems have superior advantages including high stability, relative ease and low cost of preparation, resistance to elevated temperature, and pressure and potential application to various target molecules. In view of these considerations, molecularly imprinted systems have found application in various fields of analytical chemistry including separation, purification, detection and spectrophotometric systems. Conclusion: Recent analytical methods are reported to develop the binding kinetics of imprinted systems by using the development of other technologies. The combined platforms are among the most encouraging systems to detect and recognize several molecules. The diversity of molecular imprinting methods was overviewed for different analytical application platforms. There is still a requirement of more knowledge on the molecular features of these polymers. A next step would further be the optimization of different systems with more homogeneous and easily reachable recognition sites to reduce the laborious in the accessibility in the three-dimensional polymeric materials in sufficient recognition features and also better selectivity and sensitivity for a wide range of molecules.

Atrazine-imprinted reduced graphene oxide composite with its enhanced functionalities and porous surface was successfully synthesized and applied for the selective determination of atrazine in complex matrices. Scanning electron microscopy, transmission electron microscopy, Raman spectroscopy, Fourier transform infrared spectroscopy, and X-ray diffraction studies revealed the imprinted polypyrrole beads formation on the reduced graphene oxide lining. Resultant composite was used to modify screen-printed electrode which then showed improved properties for voltammetric determination of atrazine. Measurements were carried out via square wave voltammetry giving a peak at − 0.9 V corresponding to the reduction of atrazine heterocyclic moiety. Obtained LOD and LOQ for atrazine were found to be 0.4 nmol/dm3 and 1.2 nmol/dm3, respectively, at optimized parameters. The method was applied for the atrazine determination in complex aqueous matrices.

In the present study, the enantiomeric forms of hydrophobic amino acids ( l -tryptophan, l -tyrosine, and l -phenylalanine) were separated by molecularly imprinted capillary columns (MICC) via Capillary Electrochromatography (CEC) for the first time. The monomer ratio, crosslinker ratio, template molecule ratio, the porogen ratio and type, polymerization time, and also the effect of temperature were examined to increase the permeability properties of MICC. FTIR, SEM and BET analyses were realized for the characterization of MICC. The effect of the electric field, organic solvent ratio, and pressure were carried out experimentally to determine the optimum conditions. The separation performances of MICC and the non-imprinted capillary columns (NICC) were compared electrochromatographically.

Contamination of drinking and surface waters with microorganisms is a problem that attracts attention because it threatens human health. One of the microorganisms that determine fecal contamination in water is a bacteriophage that infects coliform bacteria. A fast, real-time, sensitive, and low-cost alternative method is the nanosensor system for microorganism detection. This study aimed to develop a surface plasmon resonance nanosensor for the detection of T4 bacteriophages using nanoparticle- and nanofilm-based polymers. In this context, nanoparticle and nanofilm-based imprinted polymers were synthesized to develop nanosensors, and their efficacy was compared in fecal pollution determination in water. Following the characterization studies, nanoparticle and nanofilm-based plasmonic nanosensors were used to carry out kinetic studies in the 1 × 104–4 × 106 pfu mL−1 concentration range in buffer, sea, and tap water sample solutions. Reusability and selectivity studies were also performed. According to the results, the nanoparticle and nanofilm-based plasmonic nanosensors could measure with 98% and 81% precision, respectively. The limit of detection values was calculated as 6 × 103 pfu mL−1 and 8 × 103 pfu mL−1 for the nanoparticle and the nanofilm-based plasmonic nanosensors, respectively. In addition, the recovery value of the nanoparticle-based plasmonic nanosensor was calculated as 91–96%, while the nanofilm-based plasmonic nanosensor was calculated as 85–90% in tap and seawater samples. All results showed that both plasmonic nanosensors could detect with high selectivity, but the nanoparticle-based plasmonic nanosensor has higher sensitivity than the nanofilm-based plasmonic nanosensor.

Gene therapy is an alternative approach to insert the gene into a patient's cell to treat various diseases such as cancer, inherited disorders, and viral infections instead of using drugs or operations. For this aim, the viral and nonviral vectors are used in gene delivery studies and the nonviral vectors received significant attention because of simplicity, low-immune response, and controllability. Conducting polymers (CPs) known as Nobel Prize winner materials with unique features such as ease of synthesis, in vivo and in vitro biocompatibility, electric conductivity are promising materials for wide applications, e.g., biosensor platforms, photocatalytic applications, and biomedical studies. Furthermore, depending on the redox state, the molecules could be entrapped or released by applying the electrical stimulation; so, these conjugated polymers are also potentially used in gene delivery studies. In this context, the widely used CPs, their chemical synthesis, their interactions with DNA, siRNA, their entry into the cells, and their gene delivery performances are highlighted.

Identification of pathogens is critical as point-of-care applications, where various types of methods may be used for this purpose along with certain disadvantages for each method. To overcome these disadvantages and to build instruments that are simple, compact, user-friendly, cost-effective with quick response time and ideal for mass production are the biggest goals of research on this subject. Although many biosensing instruments are available, plasmonic makes it less difficult and more accurate to observe binding behavior at molecular level than many other types. Due to its noninvasive character, real-time, and label-free detection opportunities, plasmonic has now become an important optical biosensing platform for various applications ranging from pharmaceutical and biological sciences to diagnostic purposes and global health services. This chapter focuses on recent developments in the detection and quantification of bacteria and viruses using plasmonic biosensors based on nanoparticles, which are one of the promising candidates as biomedical instruments for medical diagnostics in the near future. Description of biosensors, including bioreceptors and transducers, and the nanoparticle-based plasmonic systems commonly used to detect the identification of bacteria and viruses are provided. Future problems and strategies are also discussed.

The accurate detection of biological substances such as proteins has always been a hot topic in scientific research. Biomimetic sensors seek to imitate sensitive and selective mechanisms of biological systems and integrate these traits into applicable sensing platforms. Molecular imprinting technology has been extensively practiced in many domains, where it can produce various molecular recognition materials with specific recognition capabilities. Molecularly imprinted polymers (MIPs), dubbed plastic antibodies, are artificial receptors with high-affinity binding sites for a particular molecule or compound. MIPs for protein recognition are expected to have high affinity via numerous interactions between polymer matrices and multiple functional groups of the target protein. This critical review briefly describes recent advances in the synthesis, characterization, and application of MIP-based sensor platforms used to detect proteins.

Breast cancer is the most common cancer in women with increasing insidance. Breast cancer occurs as a result of some molecular changes, such as aberrant or dysregulated expression of receptors, in breast epithelial cells. Therefore, breast cancer cells can be detected through their membrane receptors using specific antibodies. This study aims to form a quartz crystal microbalance (QCM) biosensor to detect breast cancer cells. Notch receptor signaling directs many pathways in developing breast tissue and its expression is found to be aberrant or disregulated in metastatic breast cancer cells. Its involvement in malignant transformation makes it a potential drug target. The human metastatic breast cancer cells, MDA MB 231 cells, are used here as a model due to the overexpression of notch-4 receptor on their membranes. First, to increase the surface area of the chip poly(2-hydroxyethyl methacrylate-PHEMA) nanoparticles were synthesized and were placed on QCM chip surface. Then, the surface was further modified and functionalized by binding notch-4 receptor antibody using carbodiimide. Nanoparticle coated and antibody attached QCM chips were characterized via FTIR-ATR, ellipsometry, contact angle measurements and by atomic force microscopy. MDA MB 231 cell samples ranging in numbers between 50-300 cells/ml were introduced to the functionalized QCM chip at a flow rate of 1.0 mL/min and the resonance frequency (f0) was recorded. Then, cell samples were applied to the QCM biosensor and the resonance frequency was monitored. The binding mode fitted best to Langmuir isotherm model. Sensitivity is found to be high and the selectivity as tested by competitive adsorption of L929 mouse fibroblast cells showed that QCM biosensor was 17.5 times more selective for MDA MB 231 cells than the fibroblast cells. The chip was reusable and was stable over 3 months. These results indicate that, the notch-4 receptor antibody PHEMA nanoparticle QCM biosensor is highly selective and efficient system that may be used for cancer cell detection.

In this study, the molecular imprinting method was used to separate enantiomeric forms of chiral antidepressant drug, R,S-citalopram (R,S-CIT) in aqueous solution by CEC system combining the advantages of capillary electrophoresis (CE) and high-performance liquid chromatography (HPLC). For that, an amino acid based molecularly imprinted monolithic capillary column was designed and used as a stationary phase for selective separation of S-citalopram (S-CIT) for the first time. S-CIT was selectively separated from aqueous solution containing the other enantiomeric form of R-CIT, which is same in size and shape to the template molecule. Morphology of the molecularly imprinted (MIP S-CIT) and non-imprinted (NIP S-CIT) monolithic capillary columns was observed by scanning electron microscopy. Imprinting efficiency of MIP S-CIT monolithic capillary column used for selective S-CIT separation was verified by comparing with NIP S-CIT and calculated imprinting factor (I.F:1.81) proved the high selectivity of the MIP S-CIT for S-CIT. Cavities formed for S-CIT form enabled selective (α = 2.08) separation of the target molecule from the other enantiomeric R-CIT form. Separation was achieved in a short period of 10 minutes, with the electrophoretic mobility of 7.68 × 10-6 m2 /Vs for R,S-CIT at pH 7.0 10 mM PB and 50% ACN ratio. The performance of both MIP S-CIT and NIP S-CIT columns was estimated by repeating the R,S-CIT separations with intra-batch and inter-batch studies for reproducibility of retention times of R.S-CITs. Estimated RSD values that are lower than 2% suggest that the monolithic columns separate R,S-CIT enantiomers without losing separation efficiency. This article is protected by copyright. All rights reserved.