Dual roles of 3-aminopropyltriethoxysilane in preparing molecularly imprinted silica particles for specific recognition of target molecules

3-Aminopropyltriethoxysilane (APTES) is a silane widely used to supply amino groups for further modifications on various materials, but it is less studied as a catalyst to catalyze sol–gel silica polymerization. Here, by using APTES as the catalyst instead of the conventional basic catalysts, a novel strategy was developed to prepare silica-based molecularly imprinted polymers (MIPs). Meanwhile, APTES was employed as the functional monomer to create imprinted nanocavities for specific recognition of target molecules. The as-synthesized MIP exhibited ultra-high recognition capability due to the elimination of the detrimental effect on the imprinting performance caused by the additional catalysts. The preparation process, specificity, pH effect, binding capacity and affinity of the MIP were studied in detail. The MIP microparticles could be packed into a solid phase extraction column for removing the target molecule in water efficiently, and the molecule could easily be enriched by 40 times. The interaction of the functional monomer and template was studied by the calculation method, giving a more clear understanding of the recognition behaviours of the imprinted polymers. The strategy could be extended not only to prepare highly specific MIPs for other small phosphoric molecules, but also for biomolecules e.g. phosphorylated peptides or proteins.

A novel strategy was developed for preparing highly selective molecularly imprinted polymers using 3-aminopropyltriethoxysilane as both a functional monomer and catalyst.     

Novel fluorescence sensor for the selective recognition of tetracycline based on molecularly imprinted polymer-capped N-doped carbon dots

A novel fluorescent probe based on molecularly imprinted polymers (MIPs) coupled with N-doped carbon dots (CDs) was prepared and used for specific recognition and sensitive determination of tetracycline (TC). N-doped CDs were synthesized using citric acid as a carbon source and ethylenediamine as a nitrogen source by a microwave assisted pyrolysis method. The determination conditions such as the solvents, material amount, pH value, and temperature were optimized. The CDs-MIPs have the best quenching on TC in water. The proposed method used for TC determination in milk powder samples had a detection limit of 0.054 μg mL⁻¹ and a wide range of 0.5–30 μg mL⁻¹. Meanwhile, satisfactory recoveries were obtained ranging from 95 to 108%. Oxytetracycline, chlorotetracycline and most of the coexisting substances showed no obvious interference indicating that the CDs-MIP probe exhibited high selectivity due to the presence of imprinted sites. Charge transfer from CDs-MIPs to TC may be through the mechanism of fluorescence quenching. This work gives a feasible strategy for the synthesis of N-doped carbon dot based molecularly imprinted polymers used as a fluorescent sensor in the food analysis field.

A novel fluorescent probe based on MIP coupled with N-doped CDs was prepared and used for sensitive recognition of tetracycline.     

Drug-loaded dual targeting graphene oxide-based molecularly imprinted composite and recognition of carcino-embryonic antigen

Despite extensive research on functional graphene oxide for anticancer drug delivery, the sensitivity of traditional protein targeting ligands to the environment limits the practical applications of targeted drug delivery. A unique molecularly imprinted magnetic graphene oxide was used as a novel drug delivery system for the treatment of tumors. Molecularly imprinted polymers (MIPs) synthesized by molecular imprinting technology have the advantages of good stability against chemical and enzymatic attacks, high specificity for a target template, and resistance to harsh environments. In our work, the MIP was used for specificity to tumor cells with carcino-embryonic (CEA) tumor markers as the template, and dopamine as the functional monomer was grafted on boronic acid-functionalized magnetic graphene oxide. The structure of the nanoparticles was optimized and characterized in detail by vibrating sample magnetometry, X-ray diffraction analysis, UV-vis spectroscopy, and flow cytometry. The prepared polymer has magnetic properties, specific recognition to CEA, biocompatibility and pH sensitivity for drug delivery. Cell culture research was carried out on the tumor cells and normal cells. The composites exhibited dual targeting properties that not only magnetically target but also specifically increase the drug cytotoxicity to the tumor cells by selectively binding to CEA. On the basis of these results, this study developed a novel approach for targeting tumor cells for drug delivery without needing to modify the protein ligand.

In the research we designed a CEA-molecularly imprinted polymers using molecular imprinting technique with CEA tumor marker as template, boronic acid functionalized MGO as substrate for dual targeted delivery of drug to tumor cells.     

Preparation of monoethyl fumarate-based molecularly imprinted polymers and their application as a solid-phase extraction sorbent for the separation of scopolamine from tropane alkaloids

Molecularly imprinted polymers (MIPs) prepared using conventional functional monomers exhibit poor specific extraction of scopolamine from tropane alkaloids, which hinders their application in separation and purification. In this paper, a novel molecularly imprinted polymer (MIP) was prepared by precipitation polymerization using scopolamine as the template, monoethyl fumarate (MFMA) as a functional monomer, and ethylene dimethacrylate (EGDMA) as a cross-linker. The advantages of the supercritical fluid technology for the removal of the template were verified by comparing the efficiency of the swelling method and the Soxhlet extraction method. The prepared MFMA-based MIPs (MFMA-MIPs) showed a high adsorption capacity (49.75 mg g⁻¹) and high selectivity toward scopolamine with a selectivity coefficient of 3.5. ¹H NMR spectroscopy was performed to demonstrate the interactions between the two functional groups of the functional monomer and the template. Lastly, MFMA-MIPs were used as solid phase extraction (SPE) sorbents for scopolamine analysis. It was found that 97.0–107.0% of the template had been extracted using the SPE column from the complex of scopolamine, atropine and anisodamine. The mean recoveries of scopolamine from plant samples were 96.0–106.0% using the established method, which showed a good linearity in the range of 8.0–4.0 × 10⁴ μg L⁻¹. The results showed that MFMA-MIPs could be applied for the separation of scopolamine from tropane alkaloids.

Monoethyl fumarate with two functional groups was introduced to prepare a MIP for the separation of scopolamine from tropane alkaloids.     

A facile molecularly imprinted polymer-based fluorometric assay for detection of histamine

Histamine is a biogenic amine naturally present in many body cells. It is also a contaminant that is mostly found in spoiled food. The consumption of foods containing high levels of histamine may lead to an allergy-like food poisoning. Analytical methods that can routinely screen histamine are thus urgently needed. In this paper, we developed a facile and cost-effective molecularly imprinted polymer (MIP)-based fluorometric assay to directly quantify histamine. Histamine-specific MIP nanoparticles (nanoMIPs) were synthesized using a modified solid-phase synthesis method. They were then immobilized in the wells of a microplate to bind the histamine in aqueous samples. After binding, o-phthaldialdehyde (OPA) was used to label the bound histamine, which converted the binding events into fluorescent signals. The obtained calibration curve of histamine showed a linear correlation ranging from 1.80 to 44.98 μM with the limit of detection of 1.80 μM. This method was successfully used to detect histamine in spiked diary milk with a recovery rate of more than 85%.

A new molecularly imprinted polymer (MIP)-based fluorometric assay was developed to directly quantify histamine in real samples.     

PEGylation of protein-imprinted nanocomposites sandwiching CdTe quantum dots with enhanced fluorescence sensing selectivity

Fluorescent sensors combining the selective recognition of protein molecularly imprinted polymers (MIPs) and the fluorescent sensing of quantum dots (QDs) have been studied considerably, but their fluorescence sensing selectivity for the target proteins remains to be increased. Herein, we propose a strategy for increasing the sensing selectivity by post-imprinting PEGylation of surface protein-imprinted nanocomposites with embedded QDs. With bovine hemoglobin (BHb) as a model protein template, protein MIP nanolayers were anchored over the CdTe QD decorated SiO₂ nanoparticles by the sol–gel process using aminopropyltriethoxy silane and tetraethoxysilicane. PEG chains were then grafted onto the surface of the imprinted nanostructures via the nucleophilic reaction of the surface amine groups with N-hydroxysuccinimide ester-terminal methoxy-PEG, followed by template removal. The resultant PEGylated sensors showed significantly improved aqueous dispersion stability compared with the non-PEGylated controls. More importantly, such PEGylation greatly increased the fluorescence response selectivity, with the Stern–Volmer equation based imprinting factor increasing from 2.7 to 5.4. The PEGylated sensors were applied to determine BHb in bovine serum samples with satisfactory recoveries at three spiking levels ranging from 94.3 to 103.7%, indicating their potential application in real samples.

PEGylated CdTe quantum dots containing protein-imprinted nanocomposites showing enhanced fluorescence sensing selectivity.     

Determination of sialic acid in serum samples by dispersive solid-phase extraction based on boronate-affinity magnetic hollow molecularly imprinted polymer sorbent

Boronate-affinity magnetic hollow molecularly imprinted polymers (B-MhMIPs) were prepared with sialic acid (SA) as the template, 3-aminophenylboronic acid (APBA) as the functional monomer and glycidilmethacrylate (GMA) as the co-monomer to chemisorb Fe₃O₄ nanoparticles. Furthermore, the hollow structure made the nanoparticles have more binding sites at both internal and external surfaces, which can facilitate the removal of template molecules from polymers and enhance the adsorption abilities towards SA. After optimizing, the adsorption pH was controlled at 4.0, and this was different from most cis-diol-containing compounds. Under the optimal conditions, the limit of detection for SA was 0.025 μg mL⁻¹ (n = 3). This method was applied to analyze serum samples with different spiked levels, and the recoveries of the SA were in the range of 70.9–106.2%. These results confirmed the superiority of the B-MhMIPs for selective and efficient enrichment of trace SA from complex matrices.

Boronate-affinity magnetic hollow molecularly imprinted polymers were prepared with sialic acid (SA) as a template to selectively extract SA from serum samples coupled with HPLC-UV.     

Synthesis,characterization, and evaluation of selective molecularly imprinted polymers for the fast determination of synthetic cathinones

As a kind of new psychoactive substance (NPS), synthetic cathinones have drawn great worldwide attention. In this study, molecularly imprinted polymers (MIPs), as adsorbents for the extraction and determination of 4-methyldimethcathinone (4-MDMC), were first synthesized by coprecipitation polymerization. The physicochemical analyses of MIPs were successfully performed by XRD, FTIR, FESEM and TGA techniques. Furthermore, rebinding properties of temperature and pH dependence, and selectivity and reusability tests for MIPs and non-imprinted polymers (NIPs) were performed using an ultraviolet-visible spectrometer (UV-vis). The obtained results indicate that the imprinting efficiency has strong dependence on temperature and pH, and the optimal adsorption for targets is achieved under the condition of 318 K and pH = 6.0. This means that the combination between the polymers and 4-MDMC is a strong spontaneous and endothermic process. Compared with NIPs, MIPs exhibit prominent adsorption capacity (Q_e = 9.77 mg g⁻¹, 318 K). The selectivity coefficients (k) of MIPs for 4-MDMC, methylenedioxypentedrone (βk-MBDP), 4-ethylmethcathinone (4-EMC), methoxetamine (MXE) and tetrahydrofuranylfentanyl (THF-F) were found to be 1.70, 3.49, 7.14 and 5.82, respectively. Moreover, it was found that the adsorption equilibrium was achieved within 30 min. The aim of this work is the simple synthesis of MIPs and the optimal performance of the molecular recognition of 4-MDMC. Moreover, the synthesized MIPs can be easily regenerated and repeatedly used with negligible loss of efficiency (only 9.94% loss after six times adsorption–desorption tests). Satisfying recoveries in the range of 69.3–78.9% indicate that MIPs have good applicability for analyte removal from urine samples. Ultimately, this material shows great promise for the rapid extraction and separation of synthetic cathinones, which are dissolved in the liquid for the field of criminal sciences.

Molecularly imprinted polymers, as an adsorbent for extraction and selective recognition of 4-methyldimethcathinone, were firstly synthesized through coprecipitation polymerization.     

Creating magnetic ionic liquid-molecularly imprinted polymers for selective extraction of lysozyme

A novel magnetic (Fe₃O₄) surface molecularly imprinted polymer (MIP) based on ionic liquid (IL) (Fe₃O₄@VTEO@IL-MIPs) was prepared for the selective extraction of lysozyme (Lys). As the functional monomer of the MIPs, an imidazolium-based IL with vinyl groups was prepared. It can provide multiple interactions with template molecules. The amount of IL was optimized (200 mg). Fourier transform infrared spectrometry (FT-IR), transmission electron microscopy (TEM), dynamic light scattering (DLS), thermogravimetric analysis (TGA) and a vibrating sample magnetometer (VSM) were used to characterize the MIP. The results indicate the successful formation of an imprinting polymer layer. The concentration of Lys in the supernatant was determined by UV-vis spectrophotometry at a wavelength of 280 nm. The maximum adsorption capability of the MIP is 213.7 mg g⁻¹ and the imprinting factor (IF) is 2.02. It took 2.5 h for the MIP to attain adsorption equilibrium. The structure of the protein was evaluated using circular dichroism (CD) spectra and UV-visible spectra. The adsorption performance was further investigated in detail by selective adsorption experiments, competitive rebinding tests, and reusability and stability experiments. Furthermore, it was utilized to separate the template protein from a mixture of proteins and real samples successfully because of the high adsorption capacity for Lys.

A novel magnetic (Fe₃O₄) surface molecularly imprinted polymer (MIP) based on ionic liquid (IL) (Fe₃O₄@VTEO@IL-MIPs) was prepared for the selective extraction of lysozyme (Lys).     

Molecularly imprinted polymers for selective adsorption of quinoline: theoretical and experimental studies

The effects of solvent on the synthesis of molecularly imprinted polymers (MIPs) for the selective adsorption of quinoline were evaluated in this work. The MIPs were synthesized by the “bulk” method using the quinoline molecule (IQ) as a template in different solvents, such as toluene (MIPT) and chloroform (MIPC). The adsorbents were characterized by thermogravimetric analysis (TGA), Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM), and N₂ adsorption/desorption measurements. The influences of time, adsorbate concentration, and temperature on the adsorption of quinoline by MIPT and MIPC were evaluated. Maximum adsorption capacities (q_e) of 35.23 and 24.10 mg g⁻¹ were obtained for MIPT and MIPC, respectively. Thermodynamic studies indicate that occur physisorption and a spontaneous process (Δ_adsG° < 0) entropically directed. Finally, the highest selectivity and reusability of MIPC for quinoline adsorption was ascribed to the better interaction between the chloroform and monomer, which favors the formation of porous adsorbents with higher numbers of adsorption sites.

Molecularly imprinted polymers synthesized by a one-pot synthesis absorb quinoline efficiently and selectively.     

A novel fluorescent functional monomer as the recognition element in core–shell imprinted sensors responding to concentration of 2,4,6-trichlorophenol

We have demonstrated a fluorescent functional monomer instead of the traditional functional monomers for molecularly imprinted sensors. The sensors were firstly used to selectively detect 2,4,6-trichlorophenol (2,4,6-TCP) by solid fluorescence detection without a dispersion solution. Moreover, the selectivity and anti-interference ability of the SiO₂@dye-FMIPs sensor meet the requirements of a fluorescent sensor. The novel fluorescent monomer introduced into MIP is no longer just a fluorophore without recognizing ability. The fluorescence intensity of SiO₂@dye-FMIPs showed a linear response to 2,4,6-TCP concentration in the range of 0–100 nM with a detection limit of 0.0534 nM. We could also demonstrate that such a system can not only get rid of the confines of traditional functional monomers and detection manner, but also improved the applications of MIPs sensors in sensing systems.

We have demonstrated a molecularly imprinted sensor with a fluorescent functional monomer instead of the traditional functional monomers to detect 2,4,6-TCP.     

A facile synthesis of molecularly imprinted polymers and their properties as electrochemical sensors for ethyl carbamate analysis

New molecularly imprinted polymers (MIPs), which exhibit specific recognition of ethyl carbamate (EC) have been synthesized and studied. In this process, EC was the template molecule and β-cyclodextrin derivatives were employed as functional monomers in the molecular imprinting technique (MIT). An EC molecularly imprinted sensor (EC-MIS) was prepared by using MIT surface modification. The EC-MIS was characterized by cyclic voltammetry, electrochemical impedance spectroscopy and differential pulse voltammetry. EC detection performance, binding parameters and dynamics mechanism were investigated. The result showed that the synthetic route designed was appropriate and that new MIP and EC-MIS were successfully prepared. The EC-MIS exhibited a good molecular recognition of EC. A linear relationship between current and EC concentration was observed using cyclic voltammetry and the detection limit was 5.86 μg L⁻¹. The binding constant (K = 4.75 × 10⁶ L mol⁻¹) between EC and the EC-MIS, as well as, the number of binding sites (n = 1.48) has been determined. The EC-MIS recognition mechanism for the EC is a two-step process. The sensor was applied for the determination of EC in Chinese yellow wines, and the results were in good agreement with the gas chromatography-mass spectrometry (GC-MS) method.

An ethyl carbamate (EC) molecularly imprinted sensor (EC-MIS) has been prepared. The molecular recognition properties of EC were investigated, the binding parameters determined, and the dynamic mechanism of EC-MIS recognizing EC explored.     

Electrochemical sensor based on screen printed carbon electrode–zinc oxide nano particles/molecularly imprinted-polymer (SPCE–ZnONPs/MIP) for detection of sodium dodecyl sulfate (SDS)

The foremost objective of this work is to prepare a novel electrochemical sensor-based screen-printed carbon electrode made of zinc oxide nanoparticles/molecularly imprinted polymer (SPCE–ZnONPs/MIP) and investigate its characteristics to detect sodium dodecyl sulfate (SDS). The MIP that is polyglutamic acid (PGA) film was synthesized via in situ electro-polymerization. The SDS''s recognition site was left on the surface of the PGA film after extraction using the cyclic voltammetry (CV) technique, facilitating the specific detection of SDS. Moreover, the ZnONPs (∼71 nm, polydispersity index of 0.138) were synthesized and effectively combined with the MIP by a drop-casting method, enhancing the current response. The surface of the prepared SPCE–ZnONPs/MIP was characterized by scanning electron microscopy and energy dispersive X-ray. Besides, the electrochemical performance of the SPCE–ZnONPs/MIP was also studied through CV and differential pulse voltammetry (DPV) techniques. As an outstanding result, it is observed that the current response of SPCE–ZnONPs/MIP for detection of SDS remarkably increased almost four times higher from 0.009 mA to 0.041 mA in comparison with bare SPCE. More importantly, the proposed SPCE–ZnONPs/MIP exhibited an excellent selectivity (in the presence of interfering molecules of Ca²⁺, Pb²⁺, as well as sodium dodecylbenzene sulfonate (SDBS)), sensitivity, reproducibility, and repeatability. Since the modified sensor offers portability, it is suitable for in situ environment and cosmetic monitoring.

The foremost objective of this work is to prepare a novel electrochemical sensor-based screen-printed carbon electrode made of zinc oxide nanoparticles/molecularly imprinted polymer (SPCE–ZnONPs/MIP) and investigate its characteristics to detect sodium dodecyl sulfate (SDS).     

Nano-molecularly imprinted polymers (nanoMIPs) as a novel approach to targeted drug delivery in nanomedicine

Molecularly imprinted polymers – MIPs – denote synthetic polymeric structures that selectively recognize the molecule of interest against which MIPs are templated. A number of works have demonstrated that MIPs can exceed the affinity and selectivity of natural antibodies, yet operating by the same principle of “lock and key”. In contrast to antibodies, which have certain limitations related to the minimal size of the antigen, nanoMIPs can be fabricated against almost any target molecule irrespective of its size and low immunogenicity. Furthermore, the cost of MIP production is much lower compared to the cost of antibody production. Excitingly, MIPs can be used as nanocontainers for specific delivery of therapeutics both in vitro and in vivo. The adoption of the solid phase synthesis rendered MIPs precise reproducible characteristics and, as a consequence, improved the controlled release of therapeutic payloads. These major breakthroughs paved the way for applicability of MIPs in medicine as a novel class of therapeutics. In this review, we highlight recent advances in the fabrication of MIPs, mechanisms of controlled release from the MIPs, and their applicability in biomedical research.

The review highlights the recent advances in fabrication of molecularly imprinted polymers and their applicability for drug delivery.     

The visual detection of anesthetics in fish based on an inverse opal photonic crystal sensor

A novel smart sensor for the rapid and label-free detection of benzocaine has been developed based on the combination of photonic crystal (PC) and molecular imprinting polymer (MIP) techniques. A molecularly imprinted photonic crystal (MIPC) hydrogel film was prepared via a non-covalent, self-assembly approach with a PC mould. With a highly ordered inverse opal structure, the resulting benzocaine MIPC exhibited high sensitivity, smart specificity, quick response times and good regeneration abilities. It can give rise to a readable optical signal and color change upon binding with benzocaine, with a detection limit of 16.5 μg mL⁻¹. The sensor has been successfully used to visually estimate benzocaine concentrations in fish samples. In comparison with HPLC, the developed MIPC sensor has shown satisfactory accuracy in terms of results. It has great potential for on-site screening and the visual detection of trace benzocaine in real samples.

A novel smart sensor for the rapid and label-free detection of benzocaine has been developed based on the combination of photonic crystal (PC) and molecular imprinting polymer (MIP) techniques.     

Modeling rapid and selective capture of nNOS–PSD-95 uncouplers from Sanhuang Xiexin decoction by novel molecularly imprinted polymers based on metal–organic frameworks

Novel and highly selective molecularly imprinted polymers based on the surface of metal–organic frameworks, NH₂-MIL-101(Cr) (MIL@MIP_S), were successfully fabricated to capture neuronal nitric oxide synthase–postsynaptic density protein-95 (nNOS–PSD-95) uncouplers from Sanhuang Xiexin Decoction (SXD) for stroke treatment. The resultant polymers were characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, thermogravimetric analysis, and X-ray diffraction. The performance tests revealed that MIL@MIPs had a large binding capacity, fast kinetics, and excellent selectivity. Then the obtained polymers were satisfactorily applied to solid-phase extraction coupled with high-performance liquid chromatography to selectively capture nNOS–PSD-95 uncouplers from SXD. Furthermore, the biological activities of components obtained from SXD were evaluated in vivo and in vitro. As a consequence, the components showed a potent neuroprotective effect from the MTS assay and uncoupling activity from the co-immunoprecipitation experiment. In addition, the anti-ischemic stroke assay in vivo was further investigated to determine the effect of reducing infarct size and ameliorating neurological deficit by the active components. Therefore, this present study contributes a valuable new method and new tendency to selectively capture active components for stroke treatment from SXD and other natural medicines.

Novel MIL@MIPs were prepared to rapidly capture nNOS–PSD-95 uncouplers from Sanhuang Xiexin decoction, coupled with SPE and HPLC.     

Fast quantification of fluoroquinolones in environmental water samples using molecularly imprinted polymers coupled with internal extractive electrospray ionization mass spectrometry

In this study, a facile method based on molecularly imprinted polymers (MIPs) combined with internal extractive electrospray ionization tandem mass spectrometry (iEESI-MS/MS) was developed for the quantitative analysis of fluoroquinolones (FQs) in environmental water samples. FQ molecules in water samples were captured by the MIPs, which was retained on a 0.22 μm syringe filter. Then, an electrospray solution selected as the elution solution was employed to extract the FQs from the MIPs, getting an eluate of FQs for mass spectrometric interrogation. Under the optimized experimental conditions, low limits of detection (LODs, 0.015–0.026 μg L⁻¹), with relative standard deviations (RSDs) less than 8.81% (n = 6) were obtained. The present method also provides good recoveries (91.14–103.60%) with acceptable precision (RSDs < 6.18%) and have no serious matrix effects for environmental water samples. The experimental results demonstrated that MIPs-iEESI-MS/MS has advantages including easy use, high speed (less than 3 min per sample) and high sensitivity for the analysis of FQs in environmental water samples, showing potential application in environmental science and water safety control.

A simple, fast and high-sensitivity method for quantification of fluoroquinolones in environmental water samples using MIPs-iEESI-MS.     

Molecularly imprinted polymers via reversible addition–fragmentation chain-transfer synthesis in sensing and environmental applications

Molecularly imprinted polymers (MIP) have shown their potential as artificial and selective receptors for environmental monitoring. These materials can be tailor-made to achieve a specific binding event with a template through a chosen mechanism. They are capable of emulating the recognition capacity of biological receptors with superior stability and versatility of integration in sensing platforms. Commonly, these polymers are produced by traditional free radical bulk polymerization (FRP) which may not be the most suitable for enhancing the intended properties due to the poor imprinting performance. To improve the imprinting technique and the polymer capabilities, controlled/living radical polymerization (CRP) has been used to overcome the main drawbacks of FRP. Combining CRP techniques such as RAFT (reversible addition–fragmentation chain transfer) with MIP has achieved higher selectivity, sensitivity, and sorption capacity of these polymers when implemented as the transductor element in sensors. The present work focuses on RAFT-MIP design and synthesis strategies to enhance the binding affinities and their implementation in environmental contaminant sensing applications.

Environmental contaminants constitute an ecological and health hazard, which requires green sensing. The RAFT-MIP approach for tailor-made selective receptors enhances them via binding affinities for use in environmental contaminant sensors.     

Design and synthesis of supramolecular functional monomers bearing urea and norbornene motifs

Three sets of functional monomers namely urea-based, 2-ureido-4[1H]-primidone (UPy)-based and norbornene based functional monomers were designed and synthesized. These functional monomers (FM) were obtained in decent yields using amine and isocyanate/norbornene as starting materials. Methacrylate and styrene isocyanate with 1,4-diaminobutane/tris(2-aminoethyl)amine were chosen for the synthesis of symmetrical, asymmetrical and three-branched urea-functional monomers, respectively. UPy-based FMs were synthesized with isocyanate and 2-amino-4-hydroxy-6-methylpyrimidine. The synthesis of these monomers feature short reaction times, mild reaction conditions and no need for column chromatographic purification. Furthermore, the norbornene based FM was used for preparing molecularly imprinted polymers (MIPs) by Ring-Opening Metathesis Polymerization (ROMP). Results showed that these synthetic routes represent a convenient and useful approach for synthesis of novel functional monomers.

Design and synthesis of supramolecular functional monomers bearing urea and norbornene.