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Interleukin-6 (IL-6) belongs to the cytokine family and plays a vital role in regulating immune response, bone maintenance, body temperature adjustment, and cell growth. The overexpression of IL-6 can indicate various health complications, such as anastomotic leakage, cancer, and chronic diseases. Therefore, the availability of highly sensitive and specific biosensing platforms for IL-6 detection is critical. In this study, for the first time, epitope-mediated IL-6-specific magnetic molecularly imprinted core–shell structures with fluorescent properties were synthesized using a three-step protocol, namely, magnetic nanoparticle functionalization, polymerization, and template removal following thorough optimization studies. The magnetic molecularly imprinted polymers (MMIPs) were characterized using dynamic and electrophoretic light scattering (DLS and ELS), revealing a hydrodynamic size of 169.9 nm and zeta potential of +17.1 mV, while Fourier transform infrared (FTIR) spectroscopy and fluorescence spectroscopy techniques showed characteristic peaks of the polymer and fluorescent tag, respectively. Scanning electron microscopy (SEM) and high-resolution transmission electron microscopy (HRTEM) investigations confirmed the successful encapsulation of the magnetic core within the ca. 5-nm-thick polymeric shell. The MMIP-based electrochemical sensing platform achieved a limit of detection of 0.38 pM within a linear detection range of 0.38–380 pM, indicating high affinity (dissociation constant KD = 1.6 pM) for IL-6 protein in 50% diluted serum samples. Moreover, comparative investigations with the non-imprinted control polymer demonstrated an imprinting factor of 4, confirming high selectivity. With multifunctional features, including fluorescence, magnetic properties, and target responsiveness, the synthesized MMIPs hold significant potential for application in various sensor techniques as well as imaging. [ABSTRACT FROM AUTHOR]

Pyrene removal from domestic water supply (DWS) is important due to its mutagenicity, toxicity, and carcinogenicity. Use of molecularly imprinted polymer for pyrene removal is scarce, therefore the study developed polystyrene to complement conventional water treatment methods for pyrene removal. Bulk polymerisation was used to synthesise Pyrene imprinted polystyrene (PIP) and its non-imprinted analogue (NIP). Monoliths were characterised using SEM–EDX, FT-IR, and XRD. Extraction and concentration of pyrene were determined using GC–MS. Adsorption experiments on simulated solutions of pyrene with different concentrations, pH, adsorbent dosage, time, and temperature using PIP and NIP with equilibrium studies were done. Recovery was performed, while pyrene was adsorbed using simulated experiment best conditions. Used PIP and NIP were characterised. Pre-adsorption characterisation confirmed PIP and NIP while post-adsorption showed a clogged surface for NIP, but PIP was pyrene-selective. Pyrene concentration (0.05 mg/L) in DWS was > WHO standard (0.0002 mg/L) with 100% recovery. Adsorption efficiencies ranged from 25–100% and 15–100% with varied parameters for PIP and NIP respectively. However, best adsorption conditions are pH-9, time-1 h, adsorbent dosage-0.8 g, concentration-0.001 mgL−1, and temperature-27 °C with ΔG° (KJmol−1)13.48, 13.70, 13.94 for NIP and 21.24, 21.60, 21.95 for PIP. NIP ΔH° -0.3233 KJmol−1 and ΔS, 0.046 KJmol−1 k−1, while PIP ΔH° -0.0717KJmol−1 and ΔS, 0.071 KJmol−1 k−1. Adsorption fits Langmuir isotherm compared to others with R2 of 0.9140 and 0.9540 for PIP and NIP respectively. The study showed that both PIP and NIP removed pyrene from DWS with excellent efficiencies. However, PIP showed greater selectivity for pyrene removal. [ABSTRACT FROM AUTHOR]

The alarming rise in atmospheric CO2 levels, primarily driven by fossil fuel combustion and industrial processes, has become a major contributor to global climate change. Effective CO2 capture technologies are urgently needed, particularly for the selective removal of CO2 from industrial gas streams, such as flue gas and biogas, which often contain impurities like N2 and CH4. In this study, we report the design and synthesis of novel molecularly imprinted polymers (MIPs) using 4‐vinylpyridine (4VP) and methacrylic acid (MAA) as functional monomers, and thiophene (Th) and formaldehyde (HC) as molecular templates. The MIPs were specifically engineered to create selective molecular cavities within a nanoporous polymer matrix for the efficient capture of CO2. By adjusting the molar ratios of the template to functional monomers, we optimized the molecular imprinting process to enhance CO2 selectivity over N2 and CH4. The resulting MIPs exhibited outstanding performance, with a maximum CO2/N2 selectivity of 153 at 25 bar and CO2/CH4 selectivity of 25.3 at 1 bar, significantly surpassing previously reported porous polymers and metal‐organic frameworks (MOFs) under similar conditions. Furthermore, we conducted heat of adsorption studies, which revealed the strong and selective interaction of CO2 with the imprinted cavities, confirming the superior adsorption properties of the synthesized MIPs. The study demonstrates that molecular imprinting can effectively enhance both CO2 capture capacity and selectivity, providing a cost‐efficient and scalable solution for industrial CO2 separation and purification processes. [ABSTRACT FROM AUTHOR]

Molecularly imprinted polymers (MIPs) can specifically recognize template molecules in solution with imprinted cavities. Due to their capacity for scalable production, they can be used to isolate target products from natural products for industrial production in the fields of pharmaceuticals and food. In this study, magnetic single-template molecularly imprinted polymers (St-MIPs) instead of magnetic multi-template molecularly imprinted polymers (Mt-MIPs) were prepared by surface imprinting using Schizandrol A as a template molecule and deep eutectic solvent (DES) as a functional monomer, combined with solid-phase extraction (SPE) for the adsorption and separation of Schizandrol A, Schisantherin A, Schizandrin A, and Schizandrin B from Schisandra chinensis (Turcz.) Baill. (S. chinensis) fruits extracts. The synthesized MIPs were characterized by FT-IR, TEM, SEM, TG, XRD and VSM, and their adsorption properties were also evaluated. MIPs can specifically recognize the template molecules with high reusability. The purity of the total S. chinensis lignans after SPE was 74.05%, among which that of Schizandrol A, Schisantherin A, Schizandrin A, and Schizandrin B was 33.38%, 8.69%, 16.33% and 15.67%, respectively. Moreover, the one-step synthesis of carrier was easy to operate. And St-MIPs reduced the production cost compared with Mt-MIPs. This study provides a new idea for natural product separation by molecular imprinting technology (MIT). [ABSTRACT FROM AUTHOR]

The small intestinal (SI) microbiota plays an important role in human health and disease. Current methods based on fecal analysis do not provide an accurate representation of the SI microbiome. This article introduces an ingestible sensor for the quantification of Escherichia coli (E. coli) in the SI by developing the fluorescent thread‐based ingestible pill analytical device (TPAD) using fluorescent gold nanoclusters (AuNCs) coupled with molecularly imprinted polymers (MIPs). Quantitative detection lies in the change in fluorescence signal on thread as proportional to target bacteria concentrations using a smartphone. Utilizing a pH‐sensitive enteric coating, this device facilitates localized sampling of the SI microbiome. Hydrophilic beads are employed to autonomously seal the device after sampling, offering a self‐locking mechanism. The sensor demonstrates a linear range for E. coli detection between 2.0 × 103 and 14.0 × 103 CFU mL−1 with an R2 of 0.9975 and a detection limit (LOD) of 400.0 × 102 CFU mL−1. The sensor also shows remarkable precision and acceptable accuracy for monitoring E. coli levels in in vivo animal studies compared to commercially available test kits. The developed TPAD, therefore, offers a novel, low‐cost, and non‐invasive method for rapidly diagnosing gastrointestinal (GI)‐related medical conditions and studying host–microbiome interactions. [ABSTRACT FROM AUTHOR]

In this work, a novel optical–chemical sensor for the detection of per- and polyfluorinated substances (PFASs) in a real scenario is presented. The proposed sensing approach exploits the multimode characteristics of plastic optical fibers (POFs) to achieve unconventional sensors via surface plasmon resonance (SPR) phenomena. The sensor is realized by the coupling of an SPR-POF platform with a novel chemical chip based on different polymeric nanolayers over the core of a D-shaped POF, one made up of an optical adhesive and one of a molecularly imprinted polymer (MIP) for PFAS. The chemical chip is used to launch the light into the SPR D-shaped POF platform, so the interaction between the analyte and the MIP's sites can be used to modulate the propagated light in the POFs and the SPR phenomena. Selectivity tests and dose–response curves by standard PFOA water solutions were carried out to characterize the detection range sensor response, obtaining a wide PFAS response range, from 1 ppt to 1000 ppt. Then, tests performed on river water samples collected from the Bormida river paved the way for the applicability of the proposed approach to a real scenario. [ABSTRACT FROM AUTHOR]

Abstract Pyrene removal from domestic water supply (DWS) is important due to its mutagenicity, toxicity, and carcinogenicity. Use of molecularly imprinted polymer for pyrene removal is scarce, therefore the study developed polystyrene to complement conventional water treatment methods for pyrene removal. Bulk polymerisation was used to synthesise Pyrene imprinted polystyrene (PIP) and its non-imprinted analogue (NIP). Monoliths were characterised using SEM–EDX, FT-IR, and XRD. Extraction and concentration of pyrene were determined using GC–MS. Adsorption experiments on simulated solutions of pyrene with different concentrations, pH, adsorbent dosage, time, and temperature using PIP and NIP with equilibrium studies were done. Recovery was performed, while pyrene was adsorbed using simulated experiment best conditions. Used PIP and NIP were characterised. Pre-adsorption characterisation confirmed PIP and NIP while post-adsorption showed a clogged surface for NIP, but PIP was pyrene-selective. Pyrene concentration (0.05 mg/L) in DWS was > WHO standard (0.0002 mg/L) with 100% recovery. Adsorption efficiencies ranged from 25–100% and 15–100% with varied parameters for PIP and NIP respectively. However, best adsorption conditions are pH-9, time-1 h, adsorbent dosage-0.8 g, concentration-0.001 mgL−1, and temperature-27 °C with ΔG° (KJmol−1)13.48, 13.70, 13.94 for NIP and 21.24, 21.60, 21.95 for PIP. NIP ΔH° -0.3233 KJmol−1 and ΔS, 0.046 KJmol−1 k−1, while PIP ΔH° -0.0717KJmol−1 and ΔS, 0.071 KJmol−1 k−1. Adsorption fits Langmuir isotherm compared to others with R2 of 0.9140 and 0.9540 for PIP and NIP respectively. The study showed that both PIP and NIP removed pyrene from DWS with excellent efficiencies. However, PIP showed greater selectivity for pyrene removal. Graphical Abstract

Context: Molecularly imprinted polymers (MIPs) have promising applications as synthetic antibodies for protein and peptide recognition. A critical aspect of MIP design is the selection of functional monomers and their adequate proportions to achieve materials with high recognition capacity toward their targets. To contribute to this goal, we calibrated a molecular dynamics protocol to reproduce the experimental trends in peptide recognition of 13 pre-polymerization mixtures reported in the literature for the peptide toxin melittin. Methods: Three simulation conditions were tested for each mixture by changing the box size and the number of monomers and cross-linkers surrounding the template in a solvent-explicit environment. Fully atomistic MD simulations of 350 ns were conducted with the AMBER20 software, with ff19SB parameters for the peptide, gaff2 parameters for the monomers and cross-linkers, and the OPC water model. Template-monomer interaction energies under the LIE approach showed significant differences between high-affinity and low-affinity mixtures. Simulation systems containing 100 monomers plus cross-linkers in a cubic box of 90 Å3 successfully ranked the mixtures according to their experimental performance. Systems with higher monomer densities resulted in non-specific intermolecular contacts that could not account for the experimental trends in melittin recognition. The mixture with the best recognition capacity showed preferential binding to the 13–26-α-helix, suggesting a relevant role for this segment in melittin imprinting and recognition. Our findings provide insightful information to assist the computational design of molecularly imprinted materials with a validated protocol that can be easily extended to other templates. [ABSTRACT FROM AUTHOR]

A molecularly imprinted polymer of Tenofovir (1), an FDA-approved acyclic nucleoside phosphonate with antiviral activity, was synthesized using a non-covalent approach. A pre-polymerization complex was formed between (1) and DMAEMA and in-house synthetic N1-[(2-methacryloyloxy)ethyl] thymine, with EGDMA as a cross-linker in an MeCN/H2O (9:1, 1:1) mixture as a porogen, giving an imprinting factor (IF) of 5.5 at 2.10−5 mol/L. Binding parameters were determined by the Freundlich–Langmuir model, Qmax and Ka, and well as the particle morphology for MIP and NIP. Finally, the release profiles, for MIP and NIP, were obtained at 25 °C and 37 °C, which is body temperature, in a phosphate buffer saline, pH 7.4, mimicking the blood pH value, to determine the potential sustained release of our polymeric materials. [ABSTRACT FROM AUTHOR]

In this study, a surface plasmon resonance (SPR) sensor based on modified plastic optical fibers (POFs) was combined with a specific molecularly imprinted polymer (MIP), used as a synthetic receptor, for glyphosate (GLY) determination in aqueous solutions. Since GLY is a non-selective herbicide associated with severe environmental and health problems, detecting glyphosate in environmental and biological samples remains challenging. The selective interaction between the MIP layer and GLY is monitored by exploiting the SPR phenomenon at the POF's gold surface. Experimental results show that in about ten minutes and by dropping microliter volume samples, the presented optical–chemical sensor can quantify up to three orders of magnitude of GLY concentrations, from nanomolar to micromolar, due to a thin MIP layer over the SPR surface. The developed optical–chemical sensor presents a detection limit of about 1 nM and can be used for onsite GLY measurements. Moreover, the experimental analysis demonstrated the high selectivity of the proposed POF-based chemical sensor. [ABSTRACT FROM AUTHOR]

Electrochemical molecularly imprinted polymers (e-MIPs) were grafted for the first time as a thin layer to the surface of a gold electrode to perform trace level electroanalysis of benzo(a)pyrene (BaP). This was achieved by controlled/living radical photopolymerization of a redox tracer monomer (ferrocenylmethyl methacrylate, FcMMA) with ethylene glycol dimethacrylate in the presence of benzo(a)pyrene as the template molecule. For that purpose, a novel photoiniferter-derived SAM was first deposited on the gold surface. The SAM formation was monitored by cyclic voltammetry and electrochemical impedance spectroscopy. Then, the “grafting from” of the e-MIP was achieved upon photoirradiation during a controlled time. Differential pulse voltammetry was used to quantify BaP in aqueous solution by following the modification of the signal of FcMMA. A limit of detection of 0.19 nM in water and a linear range of 0.66 nM to 4.30 nM, were determined, thus validating the enhancement of sensitivity induced by the close contact between the e-MIP and the electrode, and the improved transfer electron.

An optical–chemical sensor based on two modified plastic optical fibers (POFs) and a molecularly imprinted polymer (MIP) is realized and tested for the detection of 2-furaldehyde (2-FAL). The 2-FAL measurement is a scientific topic of great interest in different application fields, such as human health and life status monitoring in power transformers. The proposed sensor is realized by using two POFs as segmented waveguides (SW) coupled through a micro-trench milled between the fibers and then filled with a specific MIP for the 2-FAL detection. The experimental results show that the developed intensity-based sensor system is highly selective and sensitive to 2-FAL detection in aqueous solutions, with a limit of detection of about 0.04 mg L−1. The proposed sensing approach is simple and low-cost, and it shows performance comparable to that of plasmonic MIP-based sensors present in the literature for 2-FAL detection. [ABSTRACT FROM AUTHOR]

Polyimide films with molecular imprints of erythrosine and indigocarmine have been obtained. The structure and morphology of the film surfaces have been studied by scanning probe microscopy and IR spectroscopy. It has been found that the surface roughness of molecularly imprinted polymers (MIPs) increases, while the relief height amounts to 3–4 nm. The removal of template molecules leads to a redistribution of pores over sizes in the polymers with molecular imprints. The adsorption of dyes by MIP films has been carried out under static conditions. The degrees of extraction and the imprinting factors have been calculated for polymers with molecular imprints of the dyes. The high values of these parameters indicate the selectivity of MIPs to the target template molecules. [ABSTRACT FROM AUTHOR]

Sudan I is a cancer-causing chemical synthetic dye that is often illegally added to foods as a colorant. In this manuscript, based on molecularly imprinted polymers coated carbon dots (CDs@SiO2@MIPs), a novel fluorescence sensor is reported for the selective and sensitive determination of Sudan I. The sensor was prepared upon the surface of silica-coated carbon dots (CD@SiO2) by a one-pot sol-gel method using Sudan I as the template, 3-aminopropyl triethoxysilane (APTES) as the monomer, and tetraethyl orthosilicate (TEOS) as the crosslinker. Due to fluorescence resonance energy transfer, quenching occurred when CDs@SiO2@MIPs combined with Sudan I. The established sensor showed excellent recognition and performance for Sudan I with a wide linear range (1 to 120 μM) and low detection limit (0.61 μM). Furthermore, the sensor was successfully applied to determine Sudan I in chili powder and ketchup with recoveries from 89.7 to 101.7%. This work provides broad applications of fluorescence sensors based on CDs@SiO2@MIPs for the rapid analysis of food. [ABSTRACT FROM AUTHOR]

In this work, a novel optical–chemical sensor for the detection of per- and polyfluorinated substances (PFASs) in a real scenario is presented. The proposed sensing approach exploits the multimode characteristics of plastic optical fibers (POFs) to achieve unconventional sensors via surface plasmon resonance (SPR) phenomena. The sensor is realized by the coupling of an SPR-POF platform with a novel chemical chip based on different polymeric nanolayers over the core of a D-shaped POF, one made up of an optical adhesive and one of a molecularly imprinted polymer (MIP) for PFAS. The chemical chip is used to launch the light into the SPR D-shaped POF platform, so the interaction between the analyte and the MIP’s sites can be used to modulate the propagated light in the POFs and the SPR phenomena. Selectivity tests and dose–response curves by standard PFOA water solutions were carried out to characterize the detection range sensor response, obtaining a wide PFAS response range, from 1 ppt to 1000 ppt. Then, tests performed on river water samples collected from the Bormida river paved the way for the applicability of the proposed approach to a real scenario.

Curcumin is a compound of great importance in the food industry due to its biological and pharmacological properties, which include being an antioxidant, anti-inflammatory, antibacterial, antiviral, and anticarcinogenic. This paper proposes the synthesis of an electrochemical sensor based on molecularly imprinted polymers (MIPs) and MWCNT by drop casting deposited on a glassy carbon electrode (GCE) for the selective quantification of curcumin in food samples. The synthesized compounds are characterized by Fourier transform infrared (IR), Brunauer–Emmett–Teller (BET), and electrochemical techniques such as cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The optimal conditions for further experiments were determined by selecting these parameters. We examined three food products, commercial capsules, turmeric rhizomes, and commercial turmeric powder, employing both electrochemical and HPLC methods for the analysis. The electrochemical method revealed a limit of detection (LOD) value of 0.1365 µmol L−1, compared with the HPLC analysis, which gave a value of 3.55 µmol L−1. Furthermore, the MIP material demonstrated superior selectivity for the analyte compared to potential interferents. The recovery percentage, determined using the HPLC method, fell within the range of 87.5% to 102.6% [ABSTRACT FROM AUTHOR]

The development of polysaccharide drugs requires a thorough understanding of their quantitative and pharmacokinetic properties. However, the complexity of biological samples presents a challenge for direct analysis using UHPLC-QTOF MS. Therefore, it is essential to establish a method for the selective enrichment of polysaccharides. In this study, we developed an efficient method for the quantitative determination of polysaccharides by integrating magnetic molecularly imprinted polymers (MIPs) for sample pretreatment and UHPLC-QTOF MS for analysis. The MIPs were prepared using molecularly imprinted and boric acid affinity technologies, which combined the advantages of specific recognition and reversible binding to polysaccharides. The MIPs exhibited high dispersibility and uniform particle size, and adsorption experiments demonstrated their specific recognition of BG136, a polysaccharide with immunological activity. The proposed method was used for the purification and enrichment of BG136 in plasma with recoveries between 91.29% and 113.03%. This simple method demonstrated high selectivity, fast separation, and satisfactory recoveries providing an approach for polysaccharide determination with UHPLC-QTOF MS. [ABSTRACT FROM AUTHOR]

A molecularly imprinted polymer of Tenofovir (1), an FDA-approved acyclic nucleoside phosphonate with antiviral activity, was synthesized using a non-covalent approach. A pre-polymerization complex was formed between (1) and DMAEMA and in-house synthetic N1-[(2-methacryloyloxy)ethyl] thymine, with EGDMA as a cross-linker in an MeCN/H2O (9:1, 1:1) mixture as a porogen, giving an imprinting factor (IF) of 5.5 at 2.10−5 mol/L. Binding parameters were determined by the Freundlich–Langmuir model, Qmax and Ka, and well as the particle morphology for MIP and NIP. Finally, the release profiles, for MIP and NIP, were obtained at 25 °C and 37 °C, which is body temperature, in a phosphate buffer saline, pH 7.4, mimicking the blood pH value, to determine the potential sustained release of our polymeric materials.

In this study, a surface plasmon resonance (SPR) sensor based on modified plastic optical fibers (POFs) was combined with a specific molecularly imprinted polymer (MIP), used as a synthetic receptor, for glyphosate (GLY) determination in aqueous solutions. Since GLY is a non-selective herbicide associated with severe environmental and health problems, detecting glyphosate in environmental and biological samples remains challenging. The selective interaction between the MIP layer and GLY is monitored by exploiting the SPR phenomenon at the POF’s gold surface. Experimental results show that in about ten minutes and by dropping microliter volume samples, the presented optical–chemical sensor can quantify up to three orders of magnitude of GLY concentrations, from nanomolar to micromolar, due to a thin MIP layer over the SPR surface. The developed optical–chemical sensor presents a detection limit of about 1 nM and can be used for onsite GLY measurements. Moreover, the experimental analysis demonstrated the high selectivity of the proposed POF-based chemical sensor.

This study is dedicated to molecularly imprinted polymer-based sensor development for methylene blue detection. The sensor was designed by molecular imprinting of polypyrrole with phenothiazine derivative methylene blue (MB) as a template molecule. The molecularly imprinted polymer (MIP) was deposited directly on the surface of the indium tin oxide-coated glass electrode by potential cycling. Different deposition conditions, the layer's durability, and thickness impact were analysed. The working electrodes were coated with molecularly imprinted and non-imprinted polymer layers. Potential pulse chronoamperometry and cyclic voltammetry were used to study these layers. Scanning electron microscopy was used to determine the surface morphology of the polymer layers. The change in optical absorption was used as an analytical tool to evaluate the capability of the MIP layer to adsorb MB. Selectivity was monitored by tracking the optical absorption changes in the presence of Azure A. In the case of MB adsorption, linearity was observed at all evaluated calibration plots in the concentration range from 0.1 μM to 10 mM. The novelty of this article is based on the methodology in the fabrication process of the sensors for MB, where MB retains its native (non-polymerised) form during the deposition of the MIP composite. [ABSTRACT FROM AUTHOR]

Molecularly imprinted polymers (MIPs) encompass a diverse array of polymeric matrices that exhibit the unique capacity to selectively identify a designated template molecule through specific chemical moieties. Thanks to their pivotal attributes, including exceptional selectivity, extended shelf stability, and other distinct characteristics, this class of compounds has garnered interest in the development of highly responsive sensor systems. As a result, the incorporation of MIPs in crafting distinctive sensors and analytical procedures tailored for specific analytes across various domains has increasingly become a common practice within contemporary analytical chemistry. Furthermore, the range of polymers amenable to MIP formulation significantly influences the potential utilization of both conventional and innovative analytical methodologies. This versatility expands the array of possibilities in which MIP-based sensing can be employed in recognition systems. The following review summarizes the notable progress achieved within the preceding seven-year period in employing MIP-based sensing techniques for analyte determination. [ABSTRACT FROM AUTHOR]

An optical–chemical sensor based on two modified plastic optical fibers (POFs) and a molecularly imprinted polymer (MIP) is realized and tested for the detection of 2-furaldehyde (2-FAL). The 2-FAL measurement is a scientific topic of great interest in different application fields, such as human health and life status monitoring in power transformers. The proposed sensor is realized by using two POFs as segmented waveguides (SW) coupled through a micro-trench milled between the fibers and then filled with a specific MIP for the 2-FAL detection. The experimental results show that the developed intensity-based sensor system is highly selective and sensitive to 2-FAL detection in aqueous solutions, with a limit of detection of about 0.04 mg L−1. The proposed sensing approach is simple and low-cost, and it shows performance comparable to that of plasmonic MIP-based sensors present in the literature for 2-FAL detection.

Molecularly imprinted polymers (MIPs) are artificial antibodies for a target molecule. The review focuses mainly on mechanistic steps involved in forming MIPs and the role of co‐monomers and porogen. In addition, the electronic transition between different energy levels is explained with the help of the Jablonski diagram. Diverse receptor and target molecules for anchoring artificial MIPs are discussed, accentuating the synergetic effects obtained. The binding efficiency, selectivity, and sensitivity of various optical sensors are discussed intensively. In addition to this, we focused on synthesis, physical forms, characterization techniques, and microorganism detection of imprinted polymers. A brief investigation on the use of MIPs in cancer diagnosis is also included, and attention is extended to the important challenges faced in using imprinted polymers. [ABSTRACT FROM AUTHOR]

In this work, F e 2 O 3 was investigated as a doping agent for poly(methyl methacrylate) (PMMA) in order to enhance the plasmonic effect in sensors based on D-shaped plastic optical fibers (POFs). The doping procedure consists of immerging a premanufactured POF sensor chip in an iron (III) solution, avoiding repolymerization and its related disadvantages. After treatment, a sputtering process was used to deposit a gold nanofilm on the doped PMMA in order to obtain the surface plasmon resonance (SPR). More specifically, the doping procedure increases the refractive index of the POF's PMMA in contact with the gold nanofilm, improving the SPR phenomena. The doping of the PMMA was characterized by different analyses in order to determine the effectiveness of the doping procedure. Moreover, experimental results obtained by exploiting different water–glycerin solutions have been used to test the different SPR responses. The achieved bulk sensitivities confirmed the improvement of the plasmonic phenomenon with respect to a similar sensor configuration based on a not-doped PMMA SPR-POF chip. Finally, doped and non-doped SPR-POF platforms were functionalized with a molecularly imprinted polymer (MIP), specific for the bovine serum albumin (BSA) detection, to obtain dose-response curves. These experimental results confirmed an increase in binding sensitivity for the doped PMMA sensor. Therefore, a lower limit of detection (LOD), equal to 0.04 μM, has been obtained in the case of the doped PMMA sensor when compared to the one calculated for the not-doped sensor configuration equal to about 0.09 μM. [ABSTRACT FROM AUTHOR]

Apurinic/apyrimidinic endonuclease 1 (APE1) is a multifunctional DNA repair protein localized in different subcellular compartments. The mechanisms responsible for the highly regulated subcellular localization and "interactomes" of this protein are not fully understood but have been closely correlated to the posttranslational modifications in different biological context. In this work, we attempted to develop a bio‐nanocomposite with antibody‐like properties that could capture APE1 from cellular matrices to enable the comprehensive study of this protein. By fixing the template APE1 on the avidin‐modified surface of silica‐coated magnetic nanoparticles, we first added 3‐aminophenylboronic acid to react with the glycosyl residues of avidin, followed by addition of 2‐acrylamido‐2‐methylpropane sulfonic acid as the second functional monomer to perform the first step imprinting reaction. To further enhance the affinity and selectivity of the binding sites, we carried out the second step imprinting reaction with dopamine as the functional monomer. After the polymerization, we modified the nonimprinted sites with methoxypoly (ethylene glycol) amine (mPEG‐NH2). The resulting molecularly imprinted polymer‐based bio‐nanocomposite showed high affinity, specificity, and capacity for template APE1. It allowed for the extraction of APE1 from the cell lysates with high recovery and purity. Moreover, the bound protein could be effectively released from the bio‐nanocomposite with high activity. The bio‐nanocomposite offers a very useful tool for the separation of APE1 from various complex biological samples. [ABSTRACT FROM AUTHOR]

In this work, a novel optical fiber sensor system for ultra-low perfluorooctanoic acid (PFOA) detection in aqueous solutions is proposed. It is based on the connection, in series, of two different plastic optical fiber (POF) platforms: the first is a chemical chip realized by using a D-shaped POF with microholes filled with a specific molecularly imprinted polymer (MIP); the second is a typical surface plasmon resonance (SPR) sensor based on a D-shaped POF. In particular, the MIP-based chemical chip was used to launch the light inside the SPR–POF chip to change the SPR phenomenon by exploiting the PFOA–MIP interaction in the microholes. At first, experimental results were performed in water to demonstrate the applicability of the proposed sensing approach for measuring PFOA (or C8) in a concentration range of 1 ppt to 750 ppt, obtaining an ultra-low limit of detection (LOD) equal to about 0.81 ppt. Then, experimental results were carried out in simulated seawater to implement a complex matrix. The obtained results denoted a slight matrix effect, paving the way for the applicability of the proposed chemical sensing mechanism in several aqueous solutions. [ABSTRACT FROM AUTHOR]

Traditional Chinese medicine (TCM) is one of the most internationally competitive industries. In the context of TCM modernization and internationalization, TCM-related research studies have entered a fast track of development. At the same time, research of TCM is also faced with challenges, such as matrix complexity, component diversity and low level of active components. As an interdisciplinary technology, molecular imprinting technology (MIT) has gained popularity in TCM study, owing to the produced molecularly imprinted polymers (MIPs) possessing the unique features of structure predictability, recognition specificity and application universality, as well as physical robustness, thermal stability, low cost and easy preparation. Herein, we comprehensively review the recent advances of MIT for TCM studies since 2017, focusing on two main aspects including extraction/separation and purification and detection of active components, and identification analysis of hazardous components. The fundamentals of MIT are briefly outlined and emerging preparation techniques for MIPs applied in TCM are highlighted, such as surface imprinting, nanoimprinting and multitemplate and multifunctional monomer imprinting. Then, applications of MIPs in common active components research including flavonoids, alkaloids, terpenoids, glycosides and polyphenols, etc. are respectively summarized, followed by screening and enantioseparation. Related identification detection of hazardous components from TCM itself, illegal addition, or pollution residues (e.g., heavy metals, pesticides) are discussed. Moreover, the applications of MIT in new formulation of TCM, chiral drug resolution and detection of growing environment are summarized. Finally, we propose some issues still to be solved and future research directions to be expected of MIT for TCM studies. [ABSTRACT FROM AUTHOR]

Nanoparticles (NPs) represent emerging pollutants that still pose analytical challenges for their detection in environmentally relevant samples due to their extremely low concentrations, high colloidal background, and the need to perform speciation analysis. They are also one of the interfering matrices during the analysis of metal ions and contaminants in water samples. Currently, conventional analytical techniques such as Transmission Electron Microscopy (TEM) and Inductively Coupled Plasma Mass Spectrometry (ICP-MS) are used for the detection of NPs, but such techniques require bulky instrumentation and are difficult to be automated for online analysis. In this study, we aim to develop a nanoparticle-imprinted hydrogel (NPIH, NANOGEL) to detect and capture NPs in water samples. The principle of the Nanogel originates from the well-known concept of molecularly imprinted polymers (MIPs). Cadmium sulfide/Selenide/Zinc sulfide core/shell quantum dots (QDs) were used as the template NP, creating specific pore cavities in the Nanogel that can selectively bind to certain analytes. Quantification of NPs detected in water samples was then made possible by transducing this selective detection process into an analytical signal using a quartz crystal microbalance (QCM). The Nanogel was shown to demonstrate good repeatability, reproducibility, and stability in terms of its performance. The high selectivity of the Nanogel was determined to be attributed to the size of cavities and their surface characteristics. Ionic interference was present and, heavy metal cations showed an affinity for the NANOGEL synthesized; however, they were demonstrated to be minimized by the selection of porogenic solvents during the synthesis of NANOGEL. We believe that the Nanogel would provide a highly selective and sensitive approach for the detection of NPs in aqueous samples and the removal of NPs from contaminated water resources. It will serve useful in environmental applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • Synthesis of a new photoiniferter to prepare thin MIP films on the surface of a gold electrode. • Grafting of this photoiniferter on the surface of a gold electrode. • Formation of a thin polymer layer of electrochemical MIPs by a "grafting from" process on the surface of a gold electrode. • Validation of this proof of concept by measuring the LoD of benzo(a)pyrene in water. Electrochemical molecularly imprinted polymers (e-MIPs) were grafted for the first time as a thin layer to the surface of a gold electrode to perform trace level electroanalysis of benzo(a)pyrene (BaP). This was achieved by controlled/living radical photopolymerization of a redox tracer monomer (ferrocenylmethyl methacrylate, FcMMA) with ethylene glycol dimethacrylate in the presence of benzo(a)pyrene as the template molecule. For that purpose, a novel photoiniferter-derived SAM was first deposited on the gold surface. The SAM formation was monitored by cyclic voltammetry and electrochemical impedance spectroscopy. Then, the "grafting from" of the e-MIP was achieved upon photoirradiation during a controlled time. Differential pulse voltammetry was used to quantify BaP in aqueous solution by following the modification of the signal of FcMMA. A limit of detection of 0.19 nM in water and a linear range of 0.66 nM to 4.30 nM, were determined, thus validating the enhancement of sensitivity induced by the close contact between the e-MIP and the electrode, and the improved transfer electron. [ABSTRACT FROM AUTHOR]

This study is dedicated to molecularly imprinted polymer-based sensor development for methylene blue detection. The sensor was designed by molecular imprinting of polypyrrole with phenothiazine derivative methylene blue (MB) as a template molecule. The molecularly imprinted polymer (MIP) was deposited directly on the surface of the indium tin oxide-coated glass electrode by potential cycling. Different deposition conditions, the layer’s durability, and thickness impact were analysed. The working electrodes were coated with molecularly imprinted and non-imprinted polymer layers. Potential pulse chronoamperometry and cyclic voltammetry were used to study these layers. Scanning electron microscopy was used to determine the surface morphology of the polymer layers. The change in optical absorption was used as an analytical tool to evaluate the capability of the MIP layer to adsorb MB. Selectivity was monitored by tracking the optical absorption changes in the presence of Azure A. In the case of MB adsorption, linearity was observed at all evaluated calibration plots in the concentration range from 0.1 μM to 10 mM. The novelty of this article is based on the methodology in the fabrication process of the sensors for MB, where MB retains its native (non-polymerised) form during the deposition of the MIP composite.

Irbesartan is a drug used to treat hypertension and high blood pressure. Recent studies associated sartans with several forms of cancer, making removing this class of substances from the environment a high priority. The EU has categorized drugs as emerging pollutants, and they can be more potent than other substances because they were designed to operate at low concentrations. Thus, effective and sensitive methods of determining Irbesartan selectively and accurately in environmental samples are necessary. MIPs have already been used to remove pollutants from complex matrixes, so they were also chosen for this work. In particular, a polyacrylate-based MIP was used to functionalize the graphite working electrode of screen-printed cells (SPCs), aiming to develop a voltammetric method for Irbesartan sensing. The MIP composition and the experimental conditions for the electrochemical determination were optimized through a Design of Experiments (DoE) approach. The whole analysis was replicated with different SPCs obtaining similar results, which highlight the good reproducibility potential. MIP-based electrodes were also applied to determine Irbesartan in fortified tap water samples, obtaining high recovery percentages. Given the good results, the electrochemical method based on MIP-modified screen-printed electrodes is promising for quantifying Irbesartan at a trace level. [ABSTRACT FROM AUTHOR]

A novel molecularly imprinted polymer (MIP) based electrochemical sensor was developed for differential pulse voltammetric detection of silodosin (SLD), used for enlarged prostate (benign prostatic hyperplasia; BPH) treatment. A computational design was first applied for optimization of the molar ratio between silodosin (SLD, template): Methacrylic acid (MAA, functional monomer), based on which five polymeric ratios were prepared followed by testing the amount of crosslinker (ethylene glycol dimethacrylate (EGDMA)), imprinting and rebinding efficiency of the polymer. The ratio 1:4:20 was found to have the highest binding capacity for SLD, and thus, was used as a modifier for the development of modified carbon paste electrodes in presence of multiwalled carbon nanotubes (MWCNT). The sensor was electrochemically characterized using cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) measurements and morphologically using SEM, TEM and BET and its performance was optimized in terms of amounts of MIP, MWCNT, pH and other electrochemical parameters. A linear response range of 1.0×10−12–1.0×10−3 M SLD with a detection limit (S/N=3) of 1.0×10−13 M was shown. Finally, the MIP‐modified carbon paste sensor was successfully used to determine SLD in pure solutions, pharmaceutical formulations and spiked serum and urine samples. [ABSTRACT FROM AUTHOR]

An innovative optical-chemical sensor has been used to detect the 2-furaldehyde (2-FAL) in milk. The proposed sensing approach exploits the refractive index changing in a microstructured chip based on a plastic optical fiber (POF) with orthogonal micro-holes containing a specific molecularly imprinted polymer (MIP). This POF-MIP chemical chip modifies the surface plasmon resonance (SPR) phenomena excited in another sensor chip realized in POFs (SPR-POF) and connected in series. The proposed sensor configuration exploits MIP receptors avoiding any modification of the gold film of the SPR platform. This work reports the performance, particularly the high sensitivity and low detection limit, in complex matrices such as buffalo milk fortified with 2-FAL and in different commercial kinds of cow milk thermally treated for pasteurization. The measurements were carried out in about ten minutes by dropping the solution under-test on the planar D-shaped POF surface of the chemical chip. In contrast, on the gold surface of the SPR-POF platform, a water drop is always placed to excite the SPR phenomenon, which is modulated by the chemical chip via MIP-2-FAL binding. Furthermore, the experimental results demonstrated the pros and cons of the proposed sensor system. Thanks to the high sensitivity of the sensor system, the detection of 2-FAL in the diluted milk sample (1:50) was achieved. The dilution is required to reduce the interferent effect of the complex matrix. [ABSTRACT FROM AUTHOR]

A wearable, textile-based molecularly imprinted polymer (MIP) electrochemical sensor for cortisol detection in human sweat has been demonstrated. The wearable cortisol sensor was fabricated via layer-by-layer assembly (LbL) on a flexible cotton textile substrate coated with a conductive nanoporous carbon nanotube/cellulose nanocrystal (CNT/CNC) composite suspension, conductive polyaniline (PANI), and a selective cortisol-imprinted poly(glycidylmethacrylate-co-ethylene glycol dimethacrylate) (poly(GMA-co-EGDMA)) decorated with gold nanoparticles (AuNPs), or plated with gold. The cortisol sensor rapidly (<2 min) responded to 9.8–49.5 ng/mL of cortisol, with an average relative standard deviation (%RSD) of 6.4% across the dynamic range, indicating excellent precision. The cortisol sensor yielded an excellent limit of detection (LOD) of 8.00 ng/mL, which is within the typical physiological levels in human sweat. A single cortisol sensor patch could be reused 15 times over a 30-day period with no loss in performance, attesting to excellent reusability. The cortisol sensor patch was successfully verified for use in quantification of cortisol levels in human sweat. [ABSTRACT FROM AUTHOR]

Emerging zoonoses pose significant public health risks and necessitate rapid and effective treatment responses. This study enhances the technology for preparing Molecularly Imprinted Polymers (MIPs), which function as synthetic nanoparticles targeting SARS-CoV-2 receptor-binding domain (RBD), specifically the Omicron variant, thereby inhibiting its function. This study builds on previous findings by introducing precise adjustments in the formulation and process conditions to enhance particle stability and ensure better control over size and distribution, thereby overcoming the issues identified in earlier research. Following docking studies, imprinted nanoparticles were synthesized via inverse microemulsion polymerization and characterized in terms of size, morphology and surface charge. The selective recognition properties and ability of MIPs to obstruct the interaction between ACE2 and the RBD of SARS-CoV-2 were assessed in vitro, using Non-Imprinted Polymers (NIPs) as controls, and rebinding studies were conducted utilizing a Quartz Crystal Microbalance with Dissipation monitoring (QCM-D). The synthesized nanoparticles exhibited uniform dispersion and had a consistent diameter within the nanoscale range. MIPs demonstrated significant recognition properties and exhibited a concentration-dependent ability to reduce RBD binding to ACE2 without cytotoxic or sensitizing effects. MIPs-based platforms offer a promising alternative to natural antibodies for treating SARS-CoV-2 infections, therefore representing a versatile platform for managing emerging zoonoses., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper, (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

In recent years, melamine-sensing technologies have increasingly gained attention, mainly due to the misuse of the molecule as an adulterant in milk and other foods. Molecularly imprinted polymers (MIPs) are ideal candidates for the recognition of melamine in real-life samples. The prepared MIP particles were incorporated into a thermally conductive layer via micro-contact deposition and its response towards melamine was analyzed using the heat-transfer method (HTM). The sensor displayed an excellent selectivity when analyzing the thermal response to other chemicals commonly found in foods, and its applicability in food safety was demonstrated after evaluation in untreated milk samples, demonstrating a limit of detection of 6.02 μM. As the EU/US melamine legal limit in milk of 2.5 mg/kg falls within the linear range of the sensor, it can offer an innovative solution for routine screening of milk samples in order to detect adulteration with melamine. The results shown in this work thus demonstrate the great potential of a low-cost thermal platform for the detection of food adulteration in complex matrices. [ABSTRACT FROM AUTHOR]

5-Hydroxyindole-3-acetic acid (5-HIAA) is a molecular marker that can be used in the early diagnosis of carcinoid tumors, and the development of sophisticated 5-HIAA assays is therefore of great importance. Surface-enhanced Raman spectroscopy (SERS) has been widely used for the rapid and sensitive detection of disease biomarkers. Insufficient specificity for tumor markers and poor spectral reproducibility are the bottlenecks in the practical use of SERS technology. In this study, based on MIL-125 surface-loaded gold nanoparticles (Au@MIL-125), a novel strategy was proposed to obtain Au@MIL-125@molecularly imprinted polymers (MIPs) as functional SERS substrates by wrapping a thin MIP shell around the Au@MIL-125 surface for selective separation followed by a 5-HIAA assay. The Raman peak intensity ratio (I 865 /I 1078) was used to quantify 5-HIAA after a SERS spectral calibration with an embedded internal standard (i.e., 4-aminobenzenethiol) to improve the quantitative accuracy. The linear range was from 10−11 to 10−7 M, and the limit of detection (LOD) was 5.45 × 10−13 M. The method of integrating the MIPs with the metal MOF-based nanocomposites was shown to be useful in the analysis of real samples using SERS. The application of SERS for the selective and quantitative detection of analytes in real sample analysis, therefore, has great potential. [Display omitted] • Au/Mil-125/MIPs integrate the respective advantages of MOF and MIP to synergistically enhance the SERS signal. • The active molecule 4-aminothiophenol (4-ATP) is embedded into the shell of MIPs as an internal standard for spectral intensity calibration. [ABSTRACT FROM AUTHOR]

In this work, Fe2O3 was investigated as a doping agent for poly(methyl methacrylate) (PMMA) in order to enhance the plasmonic effect in sensors based on D-shaped plastic optical fibers (POFs). The doping procedure consists of immerging a premanufactured POF sensor chip in an iron (III) solution, avoiding repolymerization and its related disadvantages. After treatment, a sputtering process was used to deposit a gold nanofilm on the doped PMMA in order to obtain the surface plasmon resonance (SPR). More specifically, the doping procedure increases the refractive index of the POF’s PMMA in contact with the gold nanofilm, improving the SPR phenomena. The doping of the PMMA was characterized by different analyses in order to determine the effectiveness of the doping procedure. Moreover, experimental results obtained by exploiting different water–glycerin solutions have been used to test the different SPR responses. The achieved bulk sensitivities confirmed the improvement of the plasmonic phenomenon with respect to a similar sensor configuration based on a not-doped PMMA SPR-POF chip. Finally, doped and non-doped SPR-POF platforms were functionalized with a molecularly imprinted polymer (MIP), specific for the bovine serum albumin (BSA) detection, to obtain dose-response curves. These experimental results confirmed an increase in binding sensitivity for the doped PMMA sensor. Therefore, a lower limit of detection (LOD), equal to 0.04 μM, has been obtained in the case of the doped PMMA sensor when compared to the one calculated for the not-doped sensor configuration equal to about 0.09 μM.

Exploiting sorbents with predictable structure, specific recognition, and broad applications is a vivid strategy in analytical approaches. Molecularly imprinted polymers (MIPs)-based sample preparation techniques show promise in meeting the requirements of an ideal sample preparation method. However, concerns persist regarding the throughput and real-world applications of traditional MIPs-based sample preparation due to inherent defects. Integrating MIPs with functional materials not only presents viable solutions to these challenges but also expands composite practical applications. In this review, we examine the advancements in synthesis strategies and applications of MOFs- and COFs-based MIPs composites in various sample pretreatment techniques. The less-considered aspects of recognition characteristics of MIPs are surveyed. The attributes of MOFs and COFs as sorbents are discussed. Recent progress in the design and preparation of MOFs- and COFs-based MIPs composites is summarized, by highlighting their practical applications. Future perspectives and challenges to facilitate the development of corresponding analytical methods are outlined. [Display omitted] • Less-considered aspects of the binding characteristics of MIPs are highlighted. • Important considerations for selecting functional materials to prepare MIP-based composites are discussed. • Applications of MOF/COF-MIPs composites for sample pretreatment are surveyed. • Future prospects and challenges of the composites are proposed. [ABSTRACT FROM AUTHOR]

Disinfection by-products (DBPs) with heritage toxicity, mutagenicity and carcinogenicity are one kind of important new pollutants, and their detection and removal in water and wastewater has become a common challenge facing mankind. Advanced functional materials with ideal selectivity, adsorption capacity and regeneration capacity provide hope for the determination of DBPs with low concentration levels and inherent molecular structural similarity. Among them, molecularly imprinted polymers (MIPs) are favored, owing to their predictable structure, specific recognition and wide applicability. Also, metal-organic frameworks (MOFs) and covalent-organic frameworks (COFs) with unique pore structure, large specific surface area and easy functionalization, attract increasing interest. Herein, we review recent advances in analytical methods based on the above-mentioned three functional materials for DBPs in water and wastewater. Firstly, MIPs, MOFs and COFs are briefly introduced. Secondly, MIPs, MOFs and COFs as extractants, recognition element and adsorbents, are comprehensively discussed. Combining the latest research progress of solid-phase extraction (SPE), sensor, adsorption and nanofiltration, typical examples on MIPs and MOFs/COFs based analytical and removal applications in water and wastewater are summarized. Finally, the application prospects and challenges of the three functional materials in DBPs analysis are proposed to promote the development of corresponding analytical methods. [Display omitted] • MIPs, MOFs and COFs functional materials based analytical methods for DBPs. • The characteristics, advantages and applications of MIPs, MOFs and COFs. • The materials as extractant, recognition element, adsorbent and nanofiltration film. • The SPE, sensing analysis, adsorption and nanofiltration of DBPs in water/wastewater. • Insight into challenges and opportunities of the three materials in DBPs analysis. [ABSTRACT FROM AUTHOR]

Herein, we report an ultrasensitive and highly selective analytical methods to detect 2,4-dichlorophenoxyacetic acid (2,4-D) using an o -phenylenediamine based molecularly imprinted polymer (o -PD-MIP) sensor. Electrochemical Quartz Crystal Microbalance (EQCM) is used to investigate both the kinetics and the mass of the electropolymerized o -phenylenediamine. Additionally, successful removal of the template from the imprinted cavities is confirmed by comparing the XP spectra of imprinted and o-PD-MIPs after various template removal procedures. The most effective method involves a 70:30 mixture of MeOH:H 2 O for 15 min under stirring. The o -PD-MIP sensor exhibits high sensitivity with a LoD of (3 ± 1) × 10−12 M, which is below the EU regulation limits for drinking water by six orders of magnitude, a linear range between 10 and 100pM, and an excellent selectivity. These results proved the effectiveness of template removal procedure by using a 70:30 MeOH:H 2 O mixture and are a proof-of-concept for ultrasensitive and selective 2,4-D detection in real samples. [Display omitted] [ABSTRACT FROM AUTHOR]

Caffeine is a psychoactive drug that is administered as a class II psychotropic substance. It is also considered a component of analgesics and cold medicines. Excessive intake of caffeine may lead to severe health damage or drug addiction problems. The assessment of normal caffeine consumption from abusive use is not conclusive, and the cut-off value for biological samples has not been established. Herein, new cost-effective and robust all-solid-state platforms based on potentiometric transduction were fabricated and successfully utilized for caffeine assessment. The platforms were modified with reduced graphene oxide (rGO). Tailored caffeine-imprinted polymeric beads (MIPs) based on methacrylic acid (MAA) and ethylene glycol dimethacrylate (EGDMA) were prepared, characterized, and used as recognition receptors in the presented potentiometric sensing devices. In 50 mM MES buffer, the sensors exhibited a slope response of 51.2 ± 0.9 mV/decade (n = 6, R2 = 0.997) over the linear range of 4.5 × 10−6–1.0 × 10−3 M with a detection limit of 3.0 × 10−6 M. They exhibited fast detection of caffeinium ions with less than 5 s response time (<5 s). The behavior of the presented sensors towards caffeinium ions over many common organic and inorganic cations was evaluated using the modified separate solution method (MSSM). Inter-day and intra-day precision for the presented analytical device was also evaluated. Successful applications of the presented caffeine sensors for caffeine determination in commercial tea and coffee and different pharmaceutical formulations were carried out. The data obtained were compared with those obtained by the standard liquid chromatographic approach. The presented analytical device can be considered an attractive tool for caffeine determination because of its affordability and vast availability, particularly when combined with potentiometric detection. [ABSTRACT FROM AUTHOR]

Plasmonic bio/chemical sensing based on optical fibers combined with molecularly imprinted nanoparticles (nanoMIPs), which are polymeric receptors prepared by a template-assisted synthesis, has been demonstrated as a powerful method to attain ultra-low detection limits, particularly when exploiting soft nanoMIPs, which are known to deform upon analyte binding. This work presents the development of a surface plasmon resonance (SPR) sensor in silica light-diffusing fibers (LDFs) functionalized with a specific nanoMIP receptor, entailed for the recognition of the protein human serum transferrin (HTR). Despite their great versatility, to date only SPR-LFDs functionalized with antibodies have been reported. Here, the innovative combination of an SPR-LFD platform and nanoMIPs led to the development of a sensor with an ultra-low limit of detection (LOD), equal to about 4 fM, and selective for its target analyte HTR. It is worth noting that the SPR-LDF-nanoMIP sensor was mounted within a specially designed 3D-printed holder yielding a measurement cell suitable for a rapid and reliable setup, and easy for the scaling up of the measurements. Moreover, the fabrication process to realize the SPR platform is minimal, requiring only a metal deposition step. [ABSTRACT FROM AUTHOR]

[Display omitted] Ideal binding ligands for anchoring proteins are essential for the design and assembly of desirable molecularly imprinted polymers (MIPs). In this study, bovine serum albumin-MIPs (BSA-MIPs) were successfully prepared by orchestrating the involvement of orientation-controllable binding ligands via sequential thiol-ene click and thiol-ene-amine conjugation. We showed that the optimal thiol-ene-amine conjugates and binding ligands were decisive in determining the rebinding capacity and selectivity. The pyrrolidinyl MIPs exhibited the best adsorption capacity of 352 ± 22 mg/g and a superior imprinting factor of 4.72 among MIPs with various binding ligands. These favourable results were further studied by computational simulation and isothermal titration calorimetry (ITC). Molecular docking revealed the preferential binding free energy and H-bonds between BSA residues and the thiol-ene-amine conjugates. Meanwhile, the pyrrolidinyl ligand motif enabled entropy-favourable affinity to be achieved via hydrophobic effects with the BSA template by ITC thermodynamics. Because of these favourable bindings, the MIPs exhibited excellent adsorption specificity to BSA over competing proteins. The proof-of-concept of MIPs with orientation-controllable conjugates and proven binding ligands for target proteins demonstrates that this material is promising for use with a real biological sample. [ABSTRACT FROM AUTHOR]

Molecular recognition is a useful property shared by various molecules, such as antibodies, aptamers and molecularly imprinted polymers (MIPs). It allows these molecules to be potentially involved in many applications including biological and pharmaceutical research, diagnostics, theranostics, therapy and drug delivery. Antibodies, naturally produced by plasma cells, have been exploited for this purpose, but they present noticeable drawbacks, above all production cost and time. Therefore, several research studies for similar applications have been carried out about MIPs and the main studies are reported in this review. MIPs, indeed, are more versatile and cost-effective than conventional antibodies, but the lack of toxicity studies and their scarce use for practical applications, make it that further investigations on this kind of molecules need to be conducted. [ABSTRACT FROM AUTHOR]