Non-covalent Imprinting Research Articles

Synthesis and sorptive properties of molecularly imprinted polymer for simultaneous isolation of catecholamines and their metabolites from biological fluids

Simultaneous quantitative analysis of catecholamines (CAs) and their respective acid metabolites in biological fluids can become a powerful tool for diagnosis and treatment of various diseases. However, selective sample preparation procedure is necessary to isolate the aforementioned analytes from the matrix. Therefore, we propose a synthetic strategy for the preparation of a molecularly imprinted sorbent with binding sites for both CAs and their respective acid metabolites. The synthesis combines noncovalent and semicovalent imprinting methods. Methylenebisacrylamide, 4-vynilbenzyl-N,N,N-trimethylammonium (3,4-dimethoxyphenyl)acetate, and 3-phenylpropylacrylate were used as the cross-linker, functional monomer 1/“dummy” template 1, and functional monomer 2/“dummy” template 2 under precipitation polymerization conditions, respectively. The polymer was characterized using Fourier Transform Infrared Spectroscopy and Scanning Electron Microscopy. The binding properties were studied by constructing adsorption isotherms and conducting competitive binding tests. The performance of the molecularly imprinted polymers (MIPs) toward CAs and the acids was described by good imprinting factors (3.1–5.6), fast-binding equilibrium, and the ability to differentiate nonmethylated CAs from methylated ones. The MIP was used to simultaneously isolate the analytes from human plasma under dispersive solid-phase extraction conditions with subsequent detection using optimized UHPLC/MS/MS procedure. As a result, no major interferences were detected which suggests that the impurities were well separated from the analytes.

Enzyme-Mimics Molecularly Imprinted Polymers Based on Metal Complexes: Electropolymerization and Electrocatalytic Application.

The development of an electrosynthesized molecularly imprinted polymer (MIP) based on a metal complex is here reported as an effective strategy for combining advantages coming from metal-ion coordination and catalytic capabilities of metallic centers with ones deriving from electropolymerization. Metal ion coordination combines the flexibility of noncovalent imprinting approaches with the strength and specificity of covalent ones representing an attractive binding mechanism in MIP design for the recognition of a vast array of analytes. In addition, such a MIP possesses catalytic properties other than recognition capability, which is not so common in MIP field. On the other hand, electropolymerization represents a highly successful way of easily anchoring MIP-based sensing layers to the transducer surface. Procedures for MIP electrosynthesis as well as for its analytical application in electrocatalytic sensing are described.

Molecularly Imprinted Solid-Phase Extraction Sorbents for the Selective Extraction of Drugs from Human Urine.

Development of molecularly imprinted solid-phase extraction (MISPE) sorbents for the removal of drugs from human urine is described. MISPE sorbents are synthesized through free radical polymerization mechanism and non-covalent imprinting approach. After the completion of the polymerization, bulk polymer is ground using an analytical mill and then wet-sieved. Later on, MISPE sorbent has been dry-packed into solid-phase extraction cartridges after the extraction of template drug molecule. Eluates from the cartridges are analyzed using a spectrophotometer or spectrofluorimeter for the determination of target analyte by referring to the calibration curves.

The Use of Piezosensors for Determination of Carboxylic Acids in the Intermediate Products of Edible Ethanol Production

The reference polymers and polymers with molecular imprints of carboxylic acids (MIPs-CA)—propionic (MIP-Propionic) and butyric (MIP-Butyric) acids—were synthesized on the surface of piezoelectric sensors using aromatic compounds by the non-covalent imprinting method. A molecularly imprinted polymer (MIP) is a polymer produced through molecular imprinting, which leaves cavities in the polymer matrix with affinity for a chosen “template” target molecule. The values of the imprinting factor and selectivity coefficients were calculated to assess the ability of MIPs-CA to recognize the target molecules. It was shown that the sensors modified by the molecularly imprinted polymers exhibited high selectivity for the acid that was a template during their synthesis. The detection limits for propionic and butyric acids were 7.40 × 10–6 and 8.81 × 10–6 g/dm3, respectively. Correctness of the carboxylic acid determination in model solutions was verified in the spike/recovery tests. The relative standard deviation was less than 10%. The modified piezoelectric sensors were tested in analysis of the intermediate products of edible ethanol production (distillate of fermentation mixture, epurate, bottom liquids of columns). The correctness of the determination of carboxylic acids in liquids was evaluated using an Agilent Technologies 7890B GC System. The difference in the results of acid determination between both methods (piezoelectric sensor and chromatography–mass spectrometry) did not exceed 6%. The modified piezosensors expand the potential of rapid determination of carboxylic acids in the intermediate products of ethyl alcohol production.

Synthesis and characterization of α-mangostin imprinted polymers and its application for solid phase extraction

α-mangostin imprinted polymers have been synthesized by a non-covalent imprinting approach with α-mangostin as a template molecule. The α-mangostin molecularly imprinted polymers (MIPs) prepared by radical polymerization using methacrylic acid, ethlylene glycol dimethacrylate, benzoyl peroxide, and acetonitrile, as a monomer, crosslinker, initiator, and porogen, respectively. The template was removed by using methanol:acetic acid 90:10 (v/v). The physical characteristics of the polymers were investigated by Fourier Transform Infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and thermogravimetric analysis (TGA). The rebinding studies were carried out by batch methods. The results exhibited that the MIPs was able to adsorb the α-mangostin at pH 2 and the contact time of 180 min. The kinetic adsorption data of α-mangostin performed the pseudo-second order model and followed the Langmuir isotherm model with the adsorption capacity of 16.19 mg.g-1. MIPs applied as a sorbent material in solid-phase extraction, namely molecularly imprinted solid-phase extraction (MISPE) and it shows the ability for enrichment and clean-up of α-mangostin from the complex matrix in medicinal herbal product and crude extract of mangosteen (Garcinia mangostana L.) pericarp. Both samples, respectively, which were spiked with α-mangostin gives recovery more than 90% after through by MISPE in all concentration ranges.

Detection of microbial contamination based on uracil-selective synthetic receptors

The here presented work is focused on the development of a method for detection of microbial contamination of food based on uracil-selective synthetic receptors. Because uracil may serve as an indicator of bacterial contamination, its selective and on-site detection may prevent spreading of foodborne diseases. The synthetic receptors were created by molecular imprinting. Molecularly imprinted polymers for selective uracil isolation were prepared by a non-covalent imprinting method using dopamine as a functional monomer. Detection of isolated uracil was performed by capillary electrophoresis with absorption detection (λ - 260 nm). The conditions of preparation of molecularly imprinted polymers, their binding properties, adsorption kinetics and selectivity were investigated in detail. Furthermore, the prepared polymer materials were used for selective isolation and detection of uracil from complex samples as tomato products by miniaturized electrophoretic system suggesting the potential of in situ analysis of real samples.

Cooperation effect of 4-vinylbenzeneboronic acid/methacrylic acid on affinity of capecitabine imprinted polymer for drug carrier

Cooperation effect of 4-vinylbenzeneboronic acid (4-VPBA) and methacrylic acid (MAA) was first used to improve the affinity of molecularly imprinted polymer (MIP) for drug delivery. The MIP was prepared using capecitabine (CAP) as template, MAA as functional monomer, 4-VPBA as auxiliary monomer, and trimethylolpropane trimethacrylate as cross-linker. The preparation conditions of the MIPs were optimized by investigating the types of functional monomers, the types of cross-linkers, the ratio of MAA to 4-VPBA, and the ratio of crosslinker to monomer. The results showed that the as-prepared MIP had the maximum imprinting factor of 4.03, which revealed this material had a specific recognition effect on the template molecules. Experiments with in vitro release indicated that the imprinted material released CAP stably for more than 10 h, while the non-imprinted polymer (NIP) released CAP only 4 h. In addition, the pharmacokinetics results from rats showed that the MIP was significantly superior to the NIP and CAP commercial drugs, and the plasma concentration of CAP reached the plateau between 3.0 and 9.0 h. These findings may extend the applicability of noncovalent molecular imprinting, particularly to the cases where the target molecule containing a cis-dihydroxy structure.

Synthesis of a Novel Molecularly Imprinted Polymer for the Sensitive and Selective Determination of Artemisinin in Urine Samples Based on Solid-Phase Extraction (SPE) and Determination with High-Performance Liquid Chromatography (HPLC)

A novel molecularly imprinted solid-phase extraction method coupled with high-performance liquid chromatography (HPLC) is reported for the sensitive and selective determination of artemisinin in urine samples. Molecularly imprinted polymers were synthesized by free-radical polymerization through a noncovalent imprinting method using artemisinin (template), methacrylic acid (functional monomer), ethylene glycol dimethacrylate (cross-linker), azobisisobutyronitrile (initiator), and acetonitrile (porogen). The adsorption properties of the artemisinin-imprinted polymers obeyed the Langmuir isotherm with 23.9 mg/g maximum adsorption capacity and pseudo-second-order kinetics with an equilibrium adsorption time of 60 min. The prepared artemisinin-imprinted polymers showed high selectivity toward artemisinin and could be used multiple times, at least five, without changes to adsorption capacity. Furthermore, the imprinted and nonimprinted particles were placed into cartridges through dry packing, and eluates collected from cartridges were subjected to high-performance liquid chromatography. The limit of quantification and limit of detection values were 4.5 µg/L and 1.3 µg/L, respectively. The recovery of artemisinin from urine samples varied between 95.7% and 100.0%, and the relative standard deviation was less than 4.0%. The results indicated the prepared sorbent can be used for simple, selective, and sensitive detection of artemisinin from urine by a combination of solid-phase extraction and high-performance liquid chromatography.

A novel electrochemical sensor based on magnetic core@shell molecularly imprinted nanocomposite (Fe3O4@graphene oxide@MIP) for sensitive and selective determination of anticancer drug capecitabine

Capecitabine, known as an anti-cancer drug, despite clinical evidence in the general society of patients, the absence of specific data from the perception of increased toxic effects in older people and randomized trials, can be harmful to the body. So, its measurement is essential. A novel electrochemical sensor was fabricated based on glassy carbon electrode (GCE) decorated by molecularly imprinted polymer (MIP)-coated magnetic nanocomposite of iron (II, III) oxide @graphene oxide (Fe3O4@GO) for the detection of capecitabine. The MIP was deposited on the surface of core@shell nanocomposite by non-covalent imprinting process. Fe3O4@GO@MIP composite was characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FT-IR) techniques. The electrochemical performance of proposed sensor was investigated by cyclic and square wave voltammetry techniques. Several parameters such as the electrochemical behavior of the modified electrodes, the type and pH value of supporting electrolyte and scan rates were studied. Under the optimized conditions, the linear range and detection limit were obtained 1.0–100.0 nM and 0.324 nM, respectively. The proposed electrode was successfully applied to the quantification of capecitabine in health human plasma and pharmaceutical samples.

Efficient Recognition and Determination of Carbamazepine and Oxcarbazepine in Aqueous and Biological Samples by Molecularly Imprinted Polymers

A molecularly imprinted polymer (MIP) of carbamazepine (CBZ) was synthesized so as to facilitate the selective extraction of CBZ from aqueous and bio-samples by using a non-covalent imprinting approach. Synthesized materials were characterized with Fourier-transform infrared spectroscopy and scanning electron microscopy studies. The imprinted polymer was evaluated and applied as a sorbent for solid-phase extraction (SPE) coupled with HPLC-UV to detect CBZ and its metabolite oxcarbazepine (OXC). The optimal conditions for molecularly imprinted SPE (MISPE) consist of the cartridge conditioning using methanol followed by triply distilled water, loading the aqueous sample and elution by methanol-acetic acid (9 : 1, v/v). The selectivity and sensitivity for pre-concentration and separation of the target analytes were studied in details, in order to build a simple and sensitive method which can act as a potential analytical strategy to monitor CBZ and OXC in the environmental and biological samples. The developed method exhibited a wide linear range (1–500 μg/L), good linearity (R2 > 0.990), and relative standard deviation <3%. The molecular recognition properties of the MIP gave rise to good recoveries for CBZ (87–98%) and OXC (72–78%) when spiked aqueous and bio-samples were percolated through the MISPE procedure. The limit of detection for CBZ and OXC were 0.488 and 0.515 μg/L, respectively. Moreover, each MISPE cartridge, when investigated for reusability test, displayed excellent recoveries for CBZ (98–94%) with enhanced reusability (10 cycles).

A novel method of molecular imprinting applied to the template cholesterol

A novel method is successfully tested for non-covalent imprinting. Conditions are used which practically exclude the formation of prepolymerization complexes. The template is cholesterol, and no so-called functional monomer is used. The polymers contain only an acrylic diester crosslinker. The porogen isopropanol prevents even hydrogen bonding between the template and the monomer in the prepolymerization solution. Despite of these apparently very disadvantageous conditions, appreciable imprinting factors for cholesterol and imprinted selectivity against some other steroids are observed, similar to other cholesterol MIPs with proven analytical usefulness.

Molecularly imprinted polymers and capillary electrophoresis for sensing phytoestrogens in milk

Dairy cow feed contains, among other ingredients, soybeans, legumes, and clover, plants that are rich in phytoestrogens. Several publications have reported a positive influence of phytoestrogens on human health; however, several unfavorable effects have also been reported. In this work, a simple, selective, and eco-friendly method of phytoestrogen isolation based on the technique of noncovalent molecular imprinting was developed. Genistein was used as a template, and dopamine was chosen as a functional monomer. A layer of molecularly imprinted polymers was created in a microtitration well plate. The binding capability and selective properties of obtained molecularly imprinted polymers were investigated. The imprinted polymers exhibited higher binding affinity toward chosen phytoestrogen than did the nonimprinted polymers. A selectivity factor of 6.94 was calculated, confirming satisfactory selectivity of the polymeric layer. The applicability of the proposed sensing method was tested by isolation of genistein from a real sample of bovine milk and combined with micellar electrokinetic capillary chromatography with UV-visible detection.

SORPTION OF CARBOXYLIC ACIDS BY MOLECULARLY IMPRINTED POLYMERS

Molecularly imprinted polymers were synthesized as selective coatings of piezoelectric sensors for determination of carboxylic acids in the intermediate fractions of rectified ethanol. Molecularly imprinted polymers were obtained by reorganizing and imidizing polyamic acid chains in N,N-dimethylformamide in the presence of a template by the non-covalent imprinting method. The ability of molecularly imprinted polymers to recognize the target templates was evaluated by studying their sorption properties in comparison with non-imprinted polymers using direct conductometry in static mode. The equilibrium time of polyimide and molecularly imprinted polymers for acetic, propionic, butyric acids is in the range of 40 - 80 min. The type of sorption isotherm of acetic acid is characteristic of polymeric materials with micropores. During the sorption of acetic acid at low concentrations, the solvent-ethanol strongly competes with the adsorbed substance due to the close molecular sizes and the presence of group -OH. The type of sorption isotherms of propionic and butyric acids refers to the monomolecular adsorption. The sorption of carboxylic acids by molecularly imprinted polyimide is carried out mainly due to the formation of hydrogen bonds between carboxyl groups of adsorbent and adsorbate. According to the sorption data, the degrees of extraction, distribution coefficients, and imprinting factor values were calculated (IF = 3.0-15.1). It is shown that the molecularly imprinted polymers for carboxylic acids have better sorption ability to acid molecules than their non-imprinted polymers. At the same time, the molecularly imprinted polymer for butyric acid has the highest sorption capacity. Thus, the possibility of using molecularly imprinted polymers for carboxylic acids based on polyimide as selective coatings of piezosensors has been established.

Determination of bisphenol A in canned food by microwave assisted extraction, molecularly imprinted polymer-solid phase extraction and liquid chromatography-mass spectrometry

Bisphenol A (BPA), a known potential endocrine disrupting compound (EDC) is expected to be present in low quantities in canned food due to its migration from the inner surface coating of cans made of epoxy resins. A selective and confirmatory analytical method, based on microwave assisted extraction (MAE), molecularly imprinted solid phase extraction (MISPE) using a polymer prepared by a non-covalent molecular imprinting technique and liquid chromatography coupled with electrospray ionization mass spectrometry (LC-ESI/MS) was developed for the determination of BPA in canned pineapple, tuna and mushrooms. First, the effect of the loading medium of hydro- organic solutions on the binding of BPA and its deuterated analogue on the MISPE sorbent was investigated. Subsequently, the effects of the experimental conditions of the microwave assisted extraction (solvent, sample mass/solvent volume, time and temperature) on the obtained recovery of BPA from canned food were assessed and the parameters were optimized to provide maximum recovery and selectivity. It was demonstrated that the combination of MAE with MISPE permits the use of a selective extraction solvent (methanol/water, 4/6, v/v), simplifying the sample preparation steps and enhancing sample clean-up of complex food matrices. The method was validated in different food matrices, using BPA-d16 as internal standard and quantitative relative recoveries were determined. The precision (RSD %) of the method ranged from 7% to 10% and the limit of detection was at low ng/g level for all food matrices. The determined concentration of BPA in commercial canned samples ranged between 7.3 and 42.3 ng/g.

Preparation of a novel mixed non-covalent and semi-covalent molecularly imprinted membrane with hierarchical pores for separation of genistein in Radix Puerariae Lobatae

In this work, a novel mixed non-covalent and semi-covalent molecularly imprinted membrane (MIM) with hierarchical pores was prepared by cryopolymerization at −18 °C and using PEG2000 and dimethyl sulfoxide ice crystals as the pore templates. The free-standing MIM was characterized by scanning electron microscope and nitrogen adsorption-desorption isotherms, and the results confirmed the formation of the hierarchical pore structure. In the static adsorption, membrane permeation and dead-end filtration experiments, the results indicated that the mixed non-covalent and semi-covalent molecular imprinting was a good method to improve the performance of MIM which had a good adsorption selectivity toward genistein due to the presence of the imprinted sites in MIM and possessed strong imprinting efficiency toward genistein even in some similar compound mixture or extract of Radix Puerariae Lobatae.

Synergistic effect of metal ions pivot and macromolecular crowding reagents on affinity of molecularly imprinted polymer

Synergistic effect of metal ions pivot and macromolecular crowding reagents was first used for improving the affinity of molecularly imprinted polymer (MIP). The MIP monolith was synthesized with oleanolic acid as template, polymethyl methacrylate (PMMA) as macromolecular crowding agent and cobalt acetate as metal ion pivot. A ternary porogenic solvent composed of 1-butyl-3-methylimidazolium tetrafluoroborate, dimethyl sulfoxide, PMMA/CHCl3 was developed to achieve desired polymers. The effect of synthetic parameters on the imprinting effect, including template content, crosslinker content, PMMA concentration, metal ion concentration was investigated. By comparing the imprinting effect of the MIPs with other MIPs prepared only using metal ion or crowder, the cooperative effect of metal ion as pivot and macromolecular crowding agent was demonstrated. The results indicated that the combination of metal ions pivot and macromolecular crowding is an effect method for improving the affinity of the MIP based on noncovalent molecular imprinting, particularly valuable to the cases in which there is inadequate functionalities for the target molecule required for imprinting.

Developing a novel sensor based on ionic liquid molecularly imprinted polymer/gold nanoparticles/graphene oxide for the selective determination of an anti-cancer drug imiquimod

Despite its useful properties, imiquimod (IMQ), known as an anti-cancer drug, can be harmful to the skin at high concentrations. Therefore, we have developed a novel electrochemical sensor to determine IMQ, for the first time. A glassy carbon electrode (GCE) was modified by a new composite comprising of ionic liquid-based molecularly imprinted polymer (MIP) and gold nanoparticles/graphene oxide (Au/GO). The MIP/Au/GO nanocomposite was synthesized through non-covalent imprinting process in the presence of IMQ, as template molecule and characterized by SEM and FT-IR. The square wave voltammetry technique (SWV) was applied for IMQ determination in 0.1 M phosphate buffer solution (PBS) at pH 7.0. Several parameters affecting the IMQ quantification were evaluated and optimized. Under the optimized conditions, the sensor presented a linear range of 0.02–20.0 μM, a limit of quantification and detection of 0.02 μM and 0.006 μM, respectively. Low RSD values indicate the good repeatability and reproducibility of the modified electrodes in preparation and determination procedures. The satisfactory results indicated that the proposed sensor could be successfully applied for IMQ determination in real samples.

CdS quantum dots-based immunoassay combined with particle imprinted polymer technology and laser ablation ICP-MS as a versatile tool for protein detection

For the first time, the combination of molecularly imprinted polymer (MIP) technology with laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) is presented with focus on an optimization of the LA-ICP-MS parameters such as laser beam diameter, laser beam fluence, and scan speed using CdS quantum dots (QDs) as a template and dopamine as a functional monomer. A non-covalent imprinting approach was employed in this study due to the simplicity of preparation. Simple oxidative polymerization of the dopamine that creates the self-assembly monolayer seems to be an ideal choice. The QDs prepared by UV light irradiation synthesis were stabilized by using mercaptosuccinic acid. Formation of a complex of QD-antibody and QD-antibody-antigen was verified by using capillary electrophoresis with laser-induced fluorescence detection. QDs and antibody were connected together via an affinity peptide linker. LA-ICP-MS was employed as a proof-of-concept for detection method of two types of immunoassay: 1) antigen extracted from the sample by MIP and subsequently overlaid/immunoreacted by QD-labelled antibodies, 2) complex of antigen, antibody, and QD formed in the sample and subsequently extracted by MIP. The first approach provided higher sensitivity (MIP/NIP), however, the second demonstrated higher selectivity. A mixture of proteins with size in range 10–250 kDa was used as a model sample to demonstrate the capability of both approaches for detection of IgG in a complex sample.

THE USE OF PIEZOSENSORS FOR DETERMINATION OF CARBOXYLIC ACIDS IN THE INTERMEDIATE PRODUCTS OF EDIBLE ETHANOL PRODUCTION

The reference polymers and polymers with molecular imprints of carboxylic acids (MIPs-CA) — propionic (MlP-Propionic) and butyric (MIP-Butyric) acids — were synthesized on the surface of piezoelectric sensors using aromatic compounds by the non-covalent imprinting method. Molecularly imprinted polymer (MIP) is a polymer produced through molecular imprinting, which leaves cavities in the polymer matrix with affinity to a chosen "template" target molecule. The values of the imprinting factor and selectivity coefficients were calculated to assess the ability of MIPs-CA to recognize the target molecules. It is shown that the sensors modified by the molecularly imprinted polymers exhibit high selectivity for the acid that was a template during their synthesis. The detection limits for propionic and buty ric acids are 7.40 x 10~6 and 8.81 x 10-6 g/dm3, respectively. Correctness of the carboxylic acid determination in model solutions was verified in the spike/recovery tests. The relative standard deviation is less than 10%. The modified piezoelectric sensors were tested in analysis of the intermediate products of edible ethanol production (distillate of fermentation mixture, epyurat, bottom liquids of columns). The correctness of the determination of carboxylic acids in liquids was evaluated using an Agilent Technological 7890B GC Systems. The difference in the results of acid determination between both methods (piezoelectric sensor and chromatography-mass spectrometry) does not exceed 6%. The modified piezosensors expand the potential of rapid determination of carboxylic acids in the intermediate products of ethyl alcohol production.

Site-specific post-imprinting modification of molecularly imprinted polymer nanocavities with a modifiable functional monomer for prostate cancer biomarker recognition

ABSTRACT Recognition of glycans of glycoproteins using biotic materials such as antibodies is challenging due to lack of antigenicity. Polymeric materials suitable for the molecular recognition of glycoproteins have attracted considerable attention. In this study, we aimed to develop abiotic molecular materials for the recognition of prostate-specific antigen (PSA), a known biomarker for prostate cancer. We used a non-covalent bonding-based molecular imprinting technique to introduce post-imprinting poly(ethylene glycol)-based capping agent into a low-affinity recognition cavity. Details of the binding properties of these groups were investigated to optimize their affinity and selectivity for PSA. Molecularly imprinted polymers (MIPs) were prepared using a bottom-up approach based on surface-initiated atom transfer radical polymerization from a PSA-conjugated sensor chip with a functional monomer-bearing carboxy and secondary amine groups as interaction and post-imprinting modification (PIM) sites, respectively. PSA was orientationally conjugated on the sensor chip through diesters between the immobilized 3-fluorophenyl boronic acid and the cis-diol groups of PSA glucans. Treatment with the capping agent selectively inactivated low-affinity recognition cavities while protecting high-affinity cavities with the addition of a low concentration of PSA as a dynamic protection agent. The MIP thickness is critical in the present molecular imprinting, as a value of less than 5 nm can enable high selectivity. We believe that the proposed strategy based on a non-covalent molecular imprinting approach combined with a PIM-based capping treatment provides a novel method for the development of highly sensitive and selective glycoprotein recognition materials for use in biomarker sensing.