Performance Of Molecularly Imprinted Polymer Research Articles

In silico and experimental study of functionalized monomer for molecularly imprinted-enoxaparin polymer: A novel green approach

Enoxaparin (enox) is a low molecular weight heparin. Enox, which has side effects of thrombocytopenia and bleeding, requires monitoring drug therapy. The analysis method of enox in the blood plasma matrix needs a prior separation method. There has not been a molecularly imprinted polymer (MIP) synthesis for enox in earlier studies. Therefore, a novel MIP of enox was synthesized via microwave synthesizer workstation. This research aims to examine the application of in silico studies in selecting functional monomers and their comparison with enoxaparin before carrying out MIP synthesis. Enox as a template was polymerized with itaconic acid (ITA) as the best functional monomer; N,N′-methylenebisacrylamide as a cross-linking agent; water as a porogen; and ammonium persulfate as an initiator. Itaconic acid was selected using the in silico to calculate binding energy, and Gibbs free energy gives the smallest values. Itaconic acid and enoxaparin ratio was computed using DFT, and GFN2-xTB found that 1:6 was the best ratio. For calculations using molecular dynamics simulations, it was found that a ratio of 1:1 was the best, the same as in laboratory experiments using the job's plot. Polymerization was performed using a microwave at room temperature (28 °C) with an ITA ratio of 1:1, 1:4, and 1:6. Nonimprinted polymers (NIP) were similarly prepared without a template as a control. All polymer particles were characterized by spectral (Fourier-transform infrared spectroscopy), thermal (thermogravimetric analysis–differential thermal gravimetry), and morphology (scanning electron microscope). The adsorption capacity for enox was carried out with MIP and NIP. The performance of MIP was evaluated by determining the imprinting factors calculated. The MIP 1:1, 1:4, and 1:6 displayed imprinting factor is 1.21, 0.68, and 0.68, respectively. The best ratio of ITA to Enox is 1:1.

SINTESIS DAN KARAKTERISASI MOLECULARLY IMPRINTED POLYMERS MENGGUNAKAN METIL METAKRILAT DAN ETILEN GLIKOL DIMETAKRILAT SEBAGAI ADSORBEN DI-(2-ETILHEKSIL) FTALAT (SYNTHESIS AND CHARACTERIZATION OF MOLECULARLY IMPRINTED POLYMERS USING METHYL METHACRYLATE AND ETHYLENE GLYCOL DIMETACRILATE AS ADSORBENT DI-(2-ETILHEKSIL) PHTHALATE)

Molecularly Imprinted Polymer (MIP) is an intelligent synthetic material because it has the ability to selectively recognize target molecules. This study aims to synthesize, characterize and analyze the performance of MIP. MIP material was synthesized using di-(2-Ethylhexyl) phthalate (DEHP) as a template molecule, methyl methacrylate (MMA) monomer combined with ethylene glycol dimethacrylate (EGDMA) as a crosslinker by precipitation polymerization method. MIP materials were characterized by SEM-EDS instrument, FTIR spectrometer, SAA instrument, and UV-Vis spectrophotometer. The test variables for the adsorption ability of MIP material on DEHP compounds were time and concentration. The results showed that the synthesized MIP was in the form of a coarse white solid with a stiff texture. Characterization with the EDS instrument showed a decrease in the mass percent of C and percent of C atoms which indicated the formation of MIP_DEHP_MMA-co-EGDMA(TE) and the surface morphology characterized by the SEM instrument was composed of small grains that tend to be uniform and have pores. The bonds that affect the formation of polymers characterized by FTIR were –C=C, –C=O, and –CO. Characterization with the SAA instrument was 142,2770 m2/g, the total pore volume was 0,2616 cm3/g and the average pore radius was 7.3562 nm, indicating mesoporous material. The optimum time for adsorption of MIP_DEHP_MMA-co-EGDMA(TE) to DEHP was 120 minutes. MIP_DEHP_MMA-co-EGDMA(TE) followed the pseudo-second-order kinetics model and the adsorption obeyed the Freundlich adsorption isotherm

Dual-Functional Monomer MIPs and Their Comparison to Mono-Functional Monomer MIPs for SPE and as Sensors.

A molecularly imprinted polymer (MIP) is a synthetic polymer that has characteristics such as natural receptors which are able to interact and bind to a specific molecule that is used as a template in the MIP polymerization process. MIPs have been widely developed because of the need for more selective, effective, and efficient methods for sample preparation, identification, isolation, and separation. The MIP compositions consist of a template, monomer, crosslinker, initiator, and porogenic solvent. Generally, MIPs are only synthesized using one type of monomer (mono-functional monomer); however, along with the development of MIPs, MIPs began to be synthesized using two types of monomers to improve the performance of MIPs. MIPs used for identification, separation, and molecular analysis have the most applications in solid-phase extraction (SPE) and as biochemical sensors. Until now, no review article has discussed the various studies carried out in recent years in relation to the synthesis of dual-functional monomer MIPs. This review is necessary, as an improvement in the performance of MIPs still needs to be explored, and a dual-functional monomer strategy is one way of overcoming the current performance limitations. In this review article, we discuss the techniques commonly used in the synthesis of dual-functional monomer MIPs, and the use of dual-functional monomer MIPs as sorbents in the MI-SPE method and as detection elements in biochemical sensors. The application of dual-functional monomer MIPs showed better selectivity and adsorption capacity in these areas when compared to mono-functional monomer MIPs. However, the combination of functional monomers must be selected properly, in order to achieve an effective synergistic effect and produce the ideal MIP characteristics. Therefore, studies regarding the synergistic effect of the MIP combination still need to be carried out to obtain MIPs with superior characteristics.

Deep learning-assisted smartphone-based molecularly imprinted electrochemiluminescence detection sensing platform: Protable device and visual monitoring furosemide

A novel, portable, and smartphone-based molecularly imprinted polymer electrochemiluminescence (MIP-ECL) sensing platform was constructed for sensitive and selective determination of furosemide (FSM). In this platform, MoSe2 nanoparticles/starch-derived biomass carbon (MoSe2/BC) nanocomposites as imprinted material, lucigenin (Luc) as the energy donor, CdS quantum dots (CdS QDs) were used as the luminophore (energy acceptor), and molecularly imprinted polymer (MIP) as the specificity recognition element to construct a MIP-ECL sensing system based on electroluminescence resonance energy transfer (ECL-RET) mechanism, which enhanced the sensitivity and the specificity of this system. Imprinted materials were characterized by SEM, TEM, XRD, FT-IR, etc. and the recognition performance of MIP was characterized using CV, EIS, and ECL methods. The elution and re-sorption of template molecules can be used as a switch to control ECL based on the signal that can be quenched by FSM. Interestingly, deep learning based on convolutional neural networks realizes batch processing of ECL signals. Additionally, this developed MIP-ECL method was established by using the traditional ECL analyzer detector for the assay of FSM with a detection limit of 4 nM in the range of 0.010 μM–100 μM. Besides, the consumer smartphone sensing platform based on deep learning showed an outstanding linear response between the R-value of the picture and the concentration of furosemide in the range of 1–70 μM with a detection limit of 0.25 μΜ, which is much lower than that the reported for other detection methods. More importantly, due to the transferability of deep learning, the smartphone-based MIP-ECL systems can facilitate the real-time monitoring of biochemical analytes in multiple fields.

Targeted extraction of pesticide from agricultural run-off using novel molecularly imprinted polymeric pendants

As a key member of benzoylurea insecticides, lufenuron exhibits a strong potential for bioaccumulation in ecosystems. Here, we report the synthesis of a molecularly imprinted polymer (MIP) and its application for selective extraction of lufenuron from agricultural runoff samples. The morphology and thermal stability of the prepared MIP was characterized by SEM and TGA, respectively. The experimental conditions for lufenuron detection were optimized through batch binding assay and response surface methodology (RSM). The MIP showcased a two-fold enhancement in binding capacity of lufenuron (74 mg g−1) relative to non-imprinted polymer (36 mg g−1), when measured through batch binding assay. Using a RSM based on central composite design, the qe value was predicted as 73.6 mg g−1 under optimal experimental conditions (e.g., pH 8). Furthermore, the percentage recovery of lufenuron was estimated as 98.8 ± 1.8% (n = 9). The adsorption kinetics of the MIP followed the pseudo-first-order model with χ2 value of 0.004 (correlation coefficient of 0.99). The limit of detection for lufenuron using MIP-based method was 3 × 10−6 µg mL−1. There was no significant decrease in the performance of MIP against lufenuron over five successive cycles.

Utilization of Synthetic Antibody for Fumonisin Determination in Feed and Food

Fumonisin contamination in food is limited around 2 – 4 ppm and in feed for different animals varies from 5 to 100 ppm. This regulation is to prevent animal and human from carcinogenic effect from fumonisins. Measurement of fumonisins frequently uses chromatography methods such as High-Performance Liquid Chromatography (HPLC) and Liquid chromatography tandem-mass spectrometry (LCMS/MS); however, the sample preparation and analysis process for these methods are costly and time consuming. Immunoassays have also been employed for detecting fumonisins in food or feed. Unfortunately, the instability of antibody to harsh condition such as high temperature and pH becomes the drawback for immunoassay method. Currently, the technology based on molecularly imprinting, which is called synthetic antibody, has been established for replacing antibody functions. Therefore, the aim of this review is to describe development of molecularly imprinted polymer (MIP) in fumonisin analysis in feed and food. Herein, the composition and production of MIP were described comprehensively. Bulk polymerization and solid phase synthesis were methods for production of MIP in micro and nano sizes. The application of MIP was reported for sample preparation as solid phase extraction measured continuously by HPLC showing the high recovery (> 60%). Then, MIP replaced antibody in direct competitive enzyme-linked immunosorbent assay (ELISA) for quantifying fumonisins in maize with high recovery (>90%) and limit detection (2 – 6 pM). Lastly, MIP was also employed in electrochemical sensor application as receptor for recognizing fumonisin in milk and maize. In conclusion, the performance of MIP has been applied successfully for fumonisin analysis comprehensively from sample preparation and quantification. The MIP would be developed for wider application for other toxins in feed or food such as veterinary drug, heavy metals, or pesticides.

A dummy molecularly imprinted solid-phase extraction coupled with liquid chromatography-tandem mass spectrometry for selective determination of four pyridine carboxylic acid herbicides in milk

We aim to develop a solid-phase extraction (SPE) based on a dummy molecularly imprinted polymer (MIP) and liquid chromatography-tandem quadrupole mass spectrometry (LC-MS/MS) for selective determination of four pyridine carboxylic acid herbicides (aminopyralid, picloram, fluroxypyr, and clopyralid) in milk samples. Using picloram as the dummy template, MIP nanocomposites with highly selective recognition and adsorption for the target molecule and its structural analogs were successfully synthesized by precipitation polymerization. Adsorption isotherms and kinetics were used to determine the adsorption performance and specific recognition mechanism of both MIPs and non-molecularly imprinted polymers (NIP). The Scatchard plot analysis revealed that two different binding sites were formed in the MIP with maximum binding capacity (Qmax) of 1171.8 μg·g−1 and 3022.5 μg·g−1, respectively. Recovery at three spiking levels of 10, 20, and 50 μg·L−1 ranged between 75.3 and 89.8% with relative standard deviations (RSDs) <14.3%.The limit of detection (LOD) was estimated to be 0.124 μg·L−1. Finally, the feasibility of the proposed methodology was successfully applied to quantify aminopyralid and another three pyridine carboxylic acid herbicides in milk.

Impedimetric Detection of Histamine in Bowel Fluids Using Synthetic Receptors with pH-Optimized Binding Characteristics

Histamine is a biogenic amine that is indispensable in the efficient functioning of various physiological systems. In previous work, a molecularly imprinted polymer (MIP) based sensor platform with impedimetric read-out was presented which could rapidly and at low cost determine histamine concentrations in buffer solutions within pH 7-9. For diagnostic applications, histamine should be detectable in a wider pH range as it mostly occurs in mildly acidic environments. To understand this pH-dependent response of the MIP sensor, we propose a statistical binding analysis model. Within this model, we predict the theoretical performance of MIP based on acrylic acid in the required pH range and verify these results experimentally by UV-vis spectroscopy, microgravimetry, and impedance spectroscopy. Using impedimetric read-out, specific and selective detection of histamine in the physiologically relevant nanomolar concentration range is possible in neutral and mildly acidic phosphate buffer. Finally, this sensor platform was used to analyze the histamine concentration of mildly acidic bowel fluid samples of several test persons. We show that this sensor provides reliable data in the relevant concentration regime, which was validated independently by enzyme-linked immuno sorbent assay (ELISA) tests.

A Study of the Various Factors That Affect the Properties of Molecularly Imprinted Polymers

We evaluated the adsorbability and selectivity of (S)-valine anilide imprinted molecularly imprinted polymer (MIP) using a batch procedure that is both independent and precise. This study revealed important information about the relationship between the performance of MIPs and experimental factors such as the components of MIP synthesis and a reaction solvent. Herein, we also describe the problems associated with the preparation of a "non-imprinted polymer," which is often used to evaluate the effect of a template molecule, and we propose a new type of reference polymer, "blank polymer."

Synthesis of molecularly imprinted polymers from AnAc for the separation of γ-oryzanol

The selectivity of gamma-oryzanol (γ-oryzanol) was recognized by molecularly imprinted polymer (MIP). Polymeric materials were successfully synthesized via thermal polymerization method using γ-oryzanol as template, anacardic acid (AnAc) as functional monomer, toluene as porogen, benzoyl peroxide (BPO) as initiator and divinylbenzene as crosslinker. Binding performance of MIPs was evaluated by MINITAP 14 for variance of analysis, linear regression analysis and adequating model through full factorial experimental technique in terms of adsorption capacity. Analysis of variance with 95% confidence level suggested significant interaction effect (amounts of template, porogen, crosslinker) on adsorption capacity of MIPs. The strongest interaction is between the amount of porogen and the amount of crosslinker. It was also found that a linear regression model for adsorption capacity represents the experimental data with the correlation coefficients (R2) greater than 0.9. The MIP synthesis with 0.8 mmol of template, 6 ml of porogen and 10 ml of crosslinker provided the highest adsorption capacity of MIP (1.14 mg/g-adsorbent). The proposed method is relatively rapid and easy to perform for the separation of γ-oryzanol in non-aqueous systems.

Metal ion mediated molecularly imprinted polymer for selective capturing antibiotics containing beta-diketone structure

A new molecularly imprinted polymer (MIP) targeting to quinolones (Qs) and tetracyclines (TCs) was synthesized using itaconic acid (ITA) and ciprofloxacin (CIP) as a functional monomer and template molecule, respectively. Factors affecting the overall performance of MIP were investigated, and the results showed that Fe 3+ ion play a vital role in the formation of MIP with high molecular imprinting effect. Meanwhile, the chelating ability of monomer, species of template molecule, as well as the molar ratio of monomer and template also contribute to the performance of the obtained MIP. Cyclic voltammetry verified that, with the participation of Fe 3+ ions, a ternary complex of ITA–Fe 3+–CIP could be formed before polymerization. Compared with conventional MIP prepared from commonly used monomer, methacrylic acid (MAA), the new MIP show significantly enhanced molecular imprinting effect and higher capacity for specific adsorption of target compounds as revealed by static and dynamic binding experiments. The MIP was successfully used as solid-phase extraction (SPE) adsorbent for enriching a broad spectrum of antibiotics containing beta-diketone structure from surface water sample. HPLC detection showed that high recovery rate (78.6–113.6%) was found in these spiked antibiotics, whereas recovery rate for the non structurally related drugs, epinephrine (EP) and dopamine (DOPA), was very low (4.7–7.6%) on the MIP cartridges. The results demonstrate that the MIP prepared by the strategy proposed in this work, could specifically target to a series of structurally related antibiotics containing beta-diketone structure.

Study on the Binding Characteristic of Methamidophos‐Specific Molecularly Imprinted Polymer and the Interactions between Template and Monomers

AbstractA new molecularly imprinted polymer (MIP) was prepared using methamidophos (MAP) as the template molecule based on non‐covalent interaction. The complexes formed between template and monomers before polymerization were characterized by 1H NMR titration test, FT‐IR and UV spectrometry study. These studies indicated that a 1:2 molecular complex formed dominantly between MAP and functional monomers. A model mainly involving cooperative hydrogen interaction was proposed by exact placement of functional groups. Association constant was estimated to be 2.894 × 106 L2/mol2. When the initial concentration of MAP was 1.0 mmol L−1, the affinity capacity of MIP was 4.23 times that of NIP. The binding performance of MIP was modeled with the Freundlich isotherm (FI) and the total number of binding sites was calculated to be 33.97 μmol/g. The MIP showed great homogeneity with a heterogeneity index of m = 0.7356. The specificity of MIP was investigated by single‐analyte binding and molecularly imprinted solid‐phase extraction (MISPE) assays using MAP and other structurally related organophorous pesticides (OPPs). The results indicated that the MIP had a marked preference for MAP.

Preparation and Aqueous Recognition of Metal Complex Imprinted Polymer Using N-vinyl-2-pyrrolidone as Functional Monomer

Abstract Using nickel(II) acetate-2,2′-dipyridyl complex as template and N-vinyl-2-pyrrolidone (NVP) as coordinate functional monomer, a new kind of metal-complexing template molecularly imprinted polymer (MIP) was prepared. The results of equilibrium binding experiments in aqueous solution showed that the MIP had higher binding capacity for nickel(II)-2,2′-dipyridyl than the non-imprinted polymer with the same chemical composition. The influences of metal ions and pH of solution on the recognition performance of MIP were investigated. The binding characteristics of MIP were evaluated by the Scatchard analysis with one-site and two-site binding equations, respectively. The results on substrate selectivity of imprinted polymer revealed that MIP had better binding affinity for template among the tested compounds.