Molecularly imprinted polymer-coated silica microbeads for high-performance liquid chromatography.

Molecularly imprinted polymer (MIP)-based chromatographic separation materials, owing to their advantages of unique selectivity, low cost, suitable reproducibility, and acceptable stability, have attracted a great deal of research in different fields. In this investigation, a new type of MIP-coated silica (MIP/SiO2) separation material was developed using sulfamethoxazole as a template; the specific recognition ability of MIP and appropriate physicochemical properties (abundant Si-OH, suitable pore structure, good stability, etc.) of SiO2 microbeads were combined. The MIP/SiO2 separation materials were characterized carefully. Then, various compounds (such as sulfonamides, ginsenosides, nucleosides, and several pesticides) were used to comprehensively evaluate the chromatographic performances of the MIP/SiO2 column. Furthermore, the chromatographic performances of the MIP/SiO2 column were compared with those of other separation materials (such as non-imprinted polymer-coated silica, C18/SiO2, and bare silica) packed columns. The resolution value of all measured compounds was more than 1.51. The column efficiencies of 13 510 plates per meter (N m-1) for sulfamethoxazole, 11 600 N m-1 for ginsenoside Rd, and 10 510 N m-1 for 2'-deoxyadenosine were obtained. The acceptable results verified that the MIP/SiO2 column can be applied to separate highly polar drugs such as sulfonamides, ginsenosides, nucleosides, and pesticides.

Functionalized nano cellulose double-template imprinted aerogel microsphere for the targeted enrichment of taxanes.

Paclitaxel, a diterpenoid isolated from the bark of Taxus wallichiana var. chinensis (Pilger) Florin, is currently showing significant therapeutic effects against a variety of cancers. Baccatin III (Bac) and 10-Deacetylbaccatin III (10-DAB) are in great demand as important precursors for the synthesis of paclitaxel. This work aims to develop a simple, rapid and highly selective, safe, and non-polluting molecularly imprinted material for 10-DAB and Bac enrichment. In this study, we innovatively prepared molecularly imprinted materials with nanocellulose aerogel microspheres and 2-vinylpyridine (2-VP) as a bifunctional monomer, and 10-DAB and Bac as bis-template molecules. In particular, functionalized nanocellulose dual-template molecularly imprinted aerogel microsphere (FNCAG-DMIM) were successfully synthesized by the bifunctional introduction of functional nanocellulose aerogel microsphere (FNCAG) modified with Polyethyleneimine (PEI) as a carrier and functional monomer, which provided a large number of recognition sites for bimodal molecules. FNCAG-DMIM showed high specificity for 10-DAB and Bac specific assays. Under the optimal experimental conditions, the adsorption capacities of FNCAG-DMIM for 10-DAB and Bac reached 52.27 mg g-1 and 53.81 mg g-1, respectively. In addition, it showed good reliability and practicality in the determination of real samples. The present study extends the research on the synthesis of natural functional monomers by molecularly imprinted materials and opens up new horizons for the targeted isolation of plant compounds by dual-template molecularly imprinted materials.

Synthesis of Boronate Affinity-Based Oriented Dummy Template-Imprinted Magnetic Nanomaterials for Rapid and Efficient Solid-Phase Extraction of Ellagic Acid from Food.

Ellagic acid (EA) is a natural polyphenol and possesses excellent in vivo bioactivity and antioxidant behaviors, which play an important role in the treatment of oxidative stress-related diseases, such as cancer. Additionally, EA is also known as a skin-whitening ingredient. The content of EA would determine its efficacy. Therefore, the accurate analysis of EA content can provide more information for the scientific consumption of EA-rich foods and cosmetics. Nevertheless, the analysis of EA in these samples is challenging due to the low concentration level and the presence of interfering components with high abundance. Molecularly imprinted polymers are highly efficient pretreatment materials in achieving specific recognition of target molecules. However, the traditional template molecule (EA) could not be absolutely removed. Hence, template leakage continues to occur during the sample preparation process, leading to a lack of accuracy in the quantification of EA in actual samples, particularly for trace analytes. In addition, another drawback of EA as an imprinting template is that EA possesses poor solubility and a high price. Gallic acid (GA), called dummy templates, was employed for the synthesis of MIPs as a solution to these challenges. The approach used in this study was boronate affinity-based oriented surface imprinting. The prepared dummy-imprinted nanoparticles exhibited several significant advantages, such as good specificity, high binding affinity ((4.89 ± 0.46) × 10-5 M), high binding capacity (6.56 ± 0.35 mg/g), fast kinetics (6 min), and low binding pH (pH 5.0) toward EA. The reproducibility of the dummy-imprinted nanoparticles was satisfactory. The dummy-imprinted nanoparticles could still be reused even after six adsorption-desorption cycles. In addition, the recoveries of the proposed method for EA at three spiked levels of analysis in strawberry and pineapple were 91.0-106.8% and 93.8-104.0%, respectively, which indicated the successful application to real samples.

Preparation of a novel DNA-imprinted sensor based on chitosan and its highly sensitive detection of Pb2.

Lead ion is very harmful to the environment, so it is very important to study its detection methods. In this study, a novel electrochemical sensor was constructed by modifying deoxyribonucleic acid (DNA) on the electrode, which can be used for the detection of Pb2+ in the environment. Part of the mixed solution of chitosan (CS) and Pb2+ template ions was dropped onto the surface of a glassy carbon electrode. CS-Pb2+ film was cross-linked through sodium tripolyphosphate. And a novel DNA-imprinted sensor was prepared by electrodepositing CS-Pb2+ thin film with gold nanoparticles (AuNPs), removing Pb2+ templates, and immobilizing specific double-stranded DNA. The electroactive area, surface morphology, sensitivity, and electrochemical reaction mechanism of the DNA-imprinted sensor were analyzed. The elementary reaction steps were studied through electrochemical reaction kinetics analysis. The experimental results indicate that the DNA-imprinted electrochemical biosensor can quantitatively detect Pb2+ in the range of 10-100 µM (R2 = 0.9935), and its detection limit is 6.5074 µM (3σ/slope). The sensitivity of the electrochemical biosensor is 1.55233 × 10-6 A/µM, and its active areas is 6.233 cm2. The desorption mechanism and adsorption mechanism have been explored through dynamic parameter analysis. The novel DNA imprinted electrochemical biosensor developed in this paper provides a robust method for detecting lead ions in solution. Additionally, it establishes a solid groundwork for detecting other metal ions.

Molecularly imprinted beads based on modified cellulose hydrogel:A novel solid phase extraction filler for specific adsorption of camptothecin.

Traditional solid phase extraction (SPE) suffers from a lack of specific adsorption. To overcome this problem, a combination of adsorption method and molecular imprinting technology by polydopamine modification was proposed to realize specific recognition of target compounds in SPE, which is of great significance to improve the separation efficiency of SPE. Cellulose hydrogel beads were prepared by dual cross-linking curing method and modified with polydopamine to make them hydrophilic and biocompatible. Subsequently, cellulose hydrogel-based molecularly imprinted beads (MIBs) were synthesized by surface molecular imprinting technology and used as novel column fillers in SPE to achieve efficient adsorption (34.16 mg·g-1) with specific selectivity towards camptothecin (CPT) in 120 min. The simulation and NMR analysis revealed that recognition mechanism of MIBs involved hydrogen bond interactions and Van der Waals effect. The MIBs were successful used in separating CPT from Camptotheca acuminata fruits, exhibiting impressive adsorption capacity (1.19 mg·g-1) and efficient recovery of CPT (81.54 %). Thus, an environmentally friendly column filler for SPE was developed, offering a promising avenue for utilizing cellulose-based materials in the selective separation of natural products.

Template bacteria-free fabrication of surface imprinted polymer-based biosensor for E. coli detection using photolithographic mimics: Hacking bacterial adhesion.

As one class of molecular imprinted polymers (MIPs), surface imprinted polymer (SIP)-based biosensors show great potential in direct whole-bacteria detection. Micro-contact imprinting, that involves stamping the template bacteria immobilized on a substrate into a pre-polymerized polymer matrix, is the most straightforward and prominent method to obtain SIP-based biosensors. However, the major drawbacks of the method arise from the requirement for fresh template bacteria and often non-reproducible bacteria distribution on the stamp substrate. Herein, we developed a positive master stamp containing photolithographic mimics of the template bacteria (E. coli) enabling reproducible fabrication of biomimetic SIP-based biosensors without the need for the "real" bacteria cells. By using atomic force and scanning electron microscopy imaging techniques, respectively, the E. coli-capturing ability of the SIP samples was tested, and compared with non-imprinted polymer (NIP)-based samples and control SIP samples, in which the cavity geometry does not match with E. coli cells. It was revealed that the presence of the biomimetic E. coli imprints with a specifically designed geometry increases the sensor E. coli-capturing ability by an "imprinting factor" of about 3. These findings show the importance of geometry-guided physical recognition in bacterial detection using SIP-based biosensors. In addition, this imprinting strategy was employed to interdigitated electrodes and QCM (quartz crystal microbalance) chips. E. coli detection performance of the sensors was demonstrated with electrochemical impedance spectroscopy (EIS) and QCM measurements with dissipation monitoring technique (QCM-D).

Hydrophilic molecularly imprinted lysozyme-BiOBr composite with enhanced visible light utilization for selective removal of trace contaminants in water.

The development of high-efficiency molecularly imprinted photocatalysts is still challenging due to the lack of hydrophilic and suitable functional monomers. In this work, the bio-sourced lysozyme was developed as the hydrophilic functional monomer, and Cu-doped BiOBr was used as the photocatalysts, to prepare a novel hydrophilic molecularly imprinted lysozyme-BiOBr composite (BiOBr-Cu/LyzMIP) with enhanced visible light utilization. Lysozyme could form a transparent layer to mitigate the light transmission obstruction caused by the surface imprinting layer, making it an ideal functional monomer. The prepared BiOBr-Cu/LyzMIP possessed red-shifted visible-light absorption edge and minor reduction of light absorbance, indicating the enhanced utilization of visible light. Accordingly, BiOBr-Cu/LyzMIP demonstrated excellent degradation rate (99.4 % in 20 min), exceptional degradation efficiency (0.211 min-1), and superior reusability. Moreover, BiOBr-Cu/LyzMIP exhibited rapid adsorption equilibrium (20 min), good imprinting factor (2.67), and favourable degradation selectivity (>1.75), indicating the good imprinting effect resulting from abundant functional groups of lysozyme. Versatility experiments on different templates suggested that the proposed approach allowed flexibility in selecting a wide range of hazardous contaminants according to practical requirements. The present work expands the application of lysozyme-based composites in the environmental field, and provides a new one-stop pathway for efficient and sustainable treatment of contaminated water.

A Ratiometric Molecularly Imprinted Sensor for Visual Detection and Removal of α-Dicarbonyl Compounds Based on Biomass Carbon Dot-Embedded Fluorescent Covalent Organic Frameworks.

α-Dicarbonyl compounds (α-DCs) are important intermediate products during the thermal processing of foods and are closely related to the development of chronic diseases in the human body. However, there remains a significant gap in the availability of rapid detection methods for α-DCs. So, the ratiometric molecularly imprinted polymers (RCDs@GCOFs@MIPs) based on red-emitting biomass carbon dots (RCDs) and green-emitting fluorescent covalent organic frameworks (GCOFs) were constructed for the detection and removal of α-DCs in food processing. The ratiometric fluorescent sensors exhibited satisfactory detection and had good spiking recoveries in milk samples. And the excellent inhibition of pyrraline (PRL) by ratiometric fluorescent sensors was verified by simulating the milk pasteurization process. In addition, rapid onsite detection of α-DCs was achieved by recognizing the RGB value of the ratiometric fluorescence sensors via the smartphone. The ratiometric fluorescence sensors presented a new strategy for detecting and removing hazardous substances in food processing.

Molecularly imprinted polymer-based SERS sensing of transferrin in human serum.

Specific detection of glycoproteins such as transferrin (TRF) related to neurological diseases, hepatoma and other diseases always plays an important role in the field of disease diagnosis. We designed an antibody-free immunoassay sensing method based on molecularly imprinted polymers (MIPs) formed by the polymerization of multiple functional monomers for the sensitive and selective detection of TRF in human serum. In the sandwich surface-enhanced Raman spectroscopy (SERS) sensor, the TRF-oriented magnetic MIP nanoparticles (Fe3O4@SiO2-MIPs) served as capture units to specifically recognize TRF and 4-mercaptophenylboronic acid-functionalized gold nanorods (MPBA-Au NRs) served as SERS probes to label the targets. In order to achieve stronger interaction between the recognition cavities of the prepared MIPs and the different amino acid fragments that make up TRF, Fe3O4@SiO2-MIPs were obtained through polycondensation reactions between more silylating reagents, enhancing the specific recognition of the entire TRF protein and achieving high IF. This sensing method exhibited a good linear response to TRF within the TRF concentration range of 0.01 ng mL-1 to 1 mg mL-1 (R2 = 0.9974), and the LOD was 0.00407 ng mL-1 (S/N = 3). The good stability, reproducibility and specificity of the resulting MIP based SERS sensor were demonstrated. The determination of TRF in human serum confirmed the feasibility of the method in practical applications.

Preparation and optimization of dummy molecularly imprinted polymer-based solid-phase extraction system for selective enrichment of p-toluene sulfonate esters genotoxic impurities.

Sulfonate esters, one class of genotoxic impurities (GTIs), have gained significant attention in recent years due to their potential to cause genetic mutations and cancer. In the current study, we employed the dummy template molecular imprinting technology with a dummy template molecule replacing the target molecule to establish a pretreatment method for samples containing p-toluene sulfonate esters. Through computer simulation and ultraviolet-visible spectroscopy analysis, the optimal functional monomer acrylamide and polymerization solvent chloroform were selected. Subsequently, a dummy template molecularly imprinted polymer (DMIP) was prepared by the precipitation polymerization method, and the polymer was characterized in morphology, particle size, and composition. The results of the adsorption and enrichment study demonstrated that the DMIP has high adsorption capability (Q = 7.88 mg/g) and favorable imprinting effects (IF = 1.37); Further, it could simultaneously adsorb three p-toluene sulfonate esters. The optimal adsorption conditions were obtained by conditional optimization of solid-phase extraction (SPE). A pH 7 solution was selected as the loading condition, the methanol/1 % phosphoric acid solution (20:80, v/v) was selected as the washing solution, and acetonitrile containing 10 % acetic acid in 6 mL was selected as the elution solvent. Finally, we determined methyl p-toluene sulfonate alkyl esters, ethyl p-toluene sulfonate alkyl esters, and isopropyl p-toluene sulfonate alkyl esters in tosufloxacin toluene sulfonate and capecitabine at the 10 ppm level (relative to 1 mg/mL active pharmaceutical ingredient (API) samples) by using DMIP-based SPE coupled with HPLC. This approach facilitated the selective enrichment of p-toluene sulfonate esters GTIs from complex API samples.

Nanomaterial-assisted molecularly imprinted polymer strategies for highly sensitive and selective determination of cefdinir and its validation using computational approach.

In this study, the first nanomaterial-supported molecularly imprinted polymer (MIP)-based electrochemical approach was proposed to achieve the successful detection of cefdinir (CFD). Here, p-amino benzoic acid (p-ABA) was used as the monomer and the photopolymerization method was chosen to form MIP on a glassy carbon electrode (GCE). ZnO nanoparticles (ZnO NPs) were added to the MIP sensor to increase sensitivity and create high porosity. Through the use of cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS), characterization investigations confirmed the alterations at each stage of the MIP production process. Electrochemical (cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS)) and scanning electron microscopy (SEM) methods were used for study the characterization studies of the MIP-based nanocomposite sensor. The measurement of MIP parameters, such as the addition of nanoparticles, the removal procedure, the rebinding period, the monomer ratio, etc., was done using the differential pulse voltammetry (DPV). The findings showed that when ZnO NPs were added, the signal was three times higher than when MIPs were used alone. Under the optimized conditions, CFD/4-ABA@ZnONPs/MIP/GCE showed a linear response in the concentration range between 7.5 pM and 100 pM with LOD and LOQ values of 2.06 pM and 6.86 pM, respectively. Anions, cations, and substances including uric acid, ascorbic acid, paracetamol, and dopamine were all used in the selectivity test. In addition, the imprinting factor (IF) study was carried out using compounds such as cefuroxime, cefazolin, cefixime, ceftazidime, and ceftriaxone, which have structural similarities with CFD, as well as impurities such as thiazolylacetyl glycine oxime (IMP-A), thiazolylacetyl glycine oxime acetal (IMP-B), and cefdinir lactone (IMP-E). The results showed that the proposed sensor was selective for CFD, as evidenced by the relative IF values of these impurities. The recovery studies of CFD were successfully applied to tablet dosage form samples, and the developed sensor demonstrated significant sensitivity and selectivity for rapid detection of CFD in tablet dosage form.

High selectivity molecularly imprinted polymer based on short amylose as bio-based functional monomers for selective extraction of λ-cyhalothrin.

Nowadays, the development of sustainable molecularly imprinted polymers (MIPs) with high selectivity is still challenging due to the limitations of bio-based functional monomers. In this study, the highly selective and porous MIPs (LC-TMIPs) were designed and prepared on short amylose (SAM) as bio-based functional monomers, λ-cyhalothrin (LC) as a template molecule, and tetrafluoroterephthalonitrile as a rigid crosslinking agent. Static, dynamic, and selective adsorption experiments were conducted to investigate the adsorption performance. The results indicated that, compared to MIPs prepared using epichlorohydrin as flexible crosslinking agents, LC-TMIPs exhibited higher imprinting factor (3.93), selectivity (5.78), and adsorption capacity (35.79 mg g-1), as well as faster adsorption/desorption kinetics. The LC-TMIPs were used as sorbents for the selective determination of LC in both apple and cucumber samples by high-performance liquid chromatography. Under the optimal extraction conditions, the recoveries of the method reached 92.1-106.1 %, with a linear range of 1.5-30 ng g-1 and a detection limit of 0.5 ng g-1. The proposed preparation method of LC-TMIPs is expected to open a new way to prepare highly selective and sustainable MIPs for hydrophobic compounds.

Ion-imprinted aminoguanidine-chitosan for selective recognition of lanthanum (III) from wastewater.

Developing a sorbent for the removal of La3+ ions from wastewater offers significant environmental and economic advantages. This study employed an ion-imprinting process to integrate La3+ ions into a newly developed derivative of aminoguanidine-chitosan (AGCS), synthesized via an innovative method. The process initiated with the modification of chitosan by attaching cyanoacetyl groups through amide bonds, yielding cyanoacetyl chitosan (CAC). This derivative underwent further modification with aminoguanidine to produce the chelating AGCS biopolymer. The binding of La3+ ions to AGCS occurred through imprinting and cross-linking with epichlorohydrin (ECH), followed by the extraction of La3+, resulting in the La3+ ion-imprinted sorbent (La-AGCS). Structural confirmation of these chitosan derivatives was established through elemental analysis, FTIR, and NMR. SEM analysis revealed that La-AGCS exhibited a more porous structure compared to the smoother non-imprinted polymer (NIP). La-AGCS demonstrated superior La3+ capture capability, with a maximum capacity of 286 ± 1 mg/g. The adsorption process, fitting the Langmuir and pseudo-second-order models, indicated a primary chemisorption mechanism. Moreover, La-AGCS displayed excellent selectivity for La3+, exhibiting selectivity coefficients ranging from 4 to 13 against other metals. This study underscores a strategic approach in designing advanced materials tailored for La3+ removal, capitalizing on specific chelator properties and ion-imprinting technology.

Development of a simple polymer-based sensor for detection of the Pirimicarb pesticide.

In this study, a sensitive and selective fluorescent chemosensor was developed for the determination of pirimicarb pesticide by adopting the surface molecular imprinting approach. The magnetic molecularly imprinted polymer (MIP) nanocomposite was prepared using pirimicarb as the template molecule, CuFe2O4 nanoparticles, and graphene quantum dots as a fluorophore (MIP-CuFe2O4/GQDs). It was then characterized using X-ray diffraction (XRD) technique, Fourier transforms infrared (FT-IR) spectroscopy, scanning electron microscope (SEM), and transmission electron microscopy (TEM). The response surface methodology (RSM) was also employed to optimize and estimate the effective parameters of pirimicarb adsorption by this polymer. According to the experimental results, the average particle size and imprinting factor (IF) of this polymer are 53.61 nm and 2.48, respectively. Moreover, this polymer has an excellent ability to adsorb pirimicarb with a removal percentage of 99.92 at pH = 7.54, initial pirimicarb concentration = 10.17 mg/L, polymer dosage = 840 mg/L, and contact time = 6.15 min. The detection of pirimicarb was performed by fluorescence spectroscopy at a concentration range of 0-50 mg/L, and a sensitivity of 15.808 a.u/mg and a limit of detection of 1.79 mg/L were obtained. Real samples with RSD less than 2 were measured using this chemosensor. Besides, the proposed chemosensor demonstrated remarkable selectivity by checking some other insecticides with similar and different molecular structures to pirimicarb, such as diazinon, deltamethrin, and chlorpyrifos.

A novel N-CNDs/PAni modified molecular imprinted polymer for ultraselective and sensitive detection of ciprofloxacin in lentic ecosystems: a dual responsive optical sensor.

The research study describes the development of a hybrid nanocomposite called nitro-doped carbon nanodots/polyaniline/molecularly imprinted polymer (N-CNDs/PAni/MIP). This composite is specifically engineered to function as a durable and flexible dual-response sensor to detect and analyze pharmaceutical organic contaminants (POCs). Powder X-Ray diffraction (PXRD), Fourier transform infrared (FT-IR), thermogravimetric analysis (TGA), transmission electron microscopy (TEM), and scanning electron microscopy (SEM) were employed to perform an exhaustive structural and morphological analysis of N-CNDs/PAni/MIP. N-CNDs/PAni/MIP emitted blue luminescence under ultraviolet irradiation and exhibited typical excitation-dependent emission properties. It can act as fluorescent probe for the detection of CIPRO with high selectivity and sensitivity with an IF value of 4.2. Furthermore, N-CNDs/PAni/MIP exhibited high peroxidase-like catalytic behavior. After adding CIPRO to the N-CNDs/PAni/MIP/TMB/H2O2 system, the blue color of the solution faded due to the reduction of blue ox-TMB to colorless TMB. Based on these two phenomena, with CIPRO as the target analyte, the N-CNDs/PAni/MIP dual sensor showed a minimal detection limit of 70 pM for the fluorescent signaling platform and 3.5 nM for the colorimetric probe with a linear range of 0.038-200 nM. The fluorometric and colorimetric assays based on N-CNDs/PAni/MIP for CIPRO detection were then successfully applied to lentic water as well as to tap water samples, demonstrating the sensitivity and dependability of the instrument. Furthermore, the synthesized PVA (N-CNDs/PAni/MIP) films enable the recognition of CIPRO, and these films have the potential to be integrated into portable sensing devices, providing a practical solution for rapid and on-site detection of CIPRO in various samples.

Molecularly Imprinted Drug Carrier for Lamotrigine-Design, Synthesis, and Characterization of Physicochemical Parameters.

This study presents the initial attempt at introducing a magnetic molecularly imprinted polymer (MIP) designed specifically for lamotrigine with the purpose of functioning as a drug carrier. First, the composition of the magnetic polymer underwent optimization based on bulk polymer adsorption studies and theoretical analyses. The magnetic MIP was synthesized from itaconic acid and ethylene glycol dimethacrylate exhibiting a drug loading capacity of 3.4 ± 0.9 µg g-1. Structural characterization was performed using powder X-ray diffraction analysis, vibrating sample magnetometry, and Fourier transform infrared spectroscopy. The resulting MIP demonstrated controlled drug released characteristics without a burst effect in the phospahe buffer saline at pH 5 and 8. These findings hold promise for the potential nasal administration of lamotrigine in future applications.

Cell-penetrating protein-recognizing polymeric nanoparticles through dynamic covalent chemistry and double imprinting.

Molecular recognition of proteins is key to their biological functions and processes such as protein-protein interactions (PPIs). The large binding interface involved and an often relatively flat binding surface make the development of selective protein-binding materials extremely challenging. A general method is reported in this work to construct protein-binding polymeric nanoparticles from cross-linked surfactant micelles. Preparation involves first dynamic covalent chemistry that encodes signature surface lysines on a protein template. A double molecular imprinting procedure fixes the binding groups on the nanoparticle for these lysine groups, meanwhile creating a binding interface complementary to the protein in size, shape, and distribution of acidic groups on the surface. These water-soluble nanoparticles possess excellent specificities for target proteins and sufficient affinities to inhibit natural PPIs such as those between cytochrome c (Cytc) and cytochrome c oxidase (CcO). With the ability to enter cells through a combination of energy-dependent and -independent pathways, they intervene apoptosis by inhibiting the PPI between Cytc and the apoptotic protease activating factor-1 (APAF1). Generality of the preparation and the excellent molecular recognition of the materials have the potential to make them powerful tools to probe protein functions in vitro and in cellulo.

A magnetic imprinted polymer nano-adsorbent with embedded quantum dots and mesoporous carbon for the microextraction of triazine herbicides.

A magnetic molecularly imprinted polymer (MMIP) adsorbent incorporating amino-functionalized magnetite nanoparticles, nitrogen-doped graphene quantum dots and mesoporous carbon (MIP@MPC@N-GQDs@Fe3O4NH2) was fabricated to extract triazine herbicides from fruit juice. The embedded magnetite nanoparticles simplified the isolation of the adsorbent from the sample solution. The N-GQDs and MPC enhanced adsorption by affinity binding with triazines. The MIP layer provided highly specific recognition sites for the selective adsorption of three target triazines. The extracted triazines were determined by high-performance liquid chromatography (HPLC) coupled with diode-array detection (DAD). The developed method exhibited linearity from 1.5 to 100.0 µg L-1 with a detection limit of 0.5 µg L-1. Recoveries from spiked fruit juice samples were in the range of 80.1- 108.4 %, with a relative standard deviation of less than 6.0 %. The developed MMIP adsorbent demonstrated good selectivity, high extraction efficiency, ease of fabrication and use, and good stability.

Polymeric membrane potentiometric sensors based on template-removal-free imprinted receptors for determination of antibiotics.

Currently, Nernstian-response-based polymeric membrane potentiometric sensors using molecularly imprinted polymers (MIPs) as receptors have been successfully developed for determination of organic ionic species. However, the preparation of these MIP receptors usually involves tedious and time-consuming template-removal procedures. Herein, a template-removal-free MIP is proposed and used as a receptor for fabrication of a potentiometric sensor. The proposed methodology not only significantly shortens the preparation time of MIP-based potentiometric sensors but also improves the batch-to-batch reproducibility of these sensors. By using antibiotic vancomycin as a model, the new concept offers a linear concentration range of 1.0 × 10-7 to 1.0 × 10-4 mol L-1 with a detection limit of 2.51 × 10-8 mol L-1. It can be expected that the template-removal-free MIP-based sensing strategy could lay the foundation for simple fabrication of electrochemical sensors without the need for template removal such as potentiometric and capacitive sensors and ion-sensitive field-effect transistors.

Unlocking New Avenues: Solid-State Synthesis of Molecularly Imprinted Polymers.

Molecularly imprinted polymers (MIPs) are established artificial molecular recognition platforms with tailored selectivity towards a target molecule, whose synthesis and functionality are highly influenced by the nature of the solvent employed in their synthesis. Steps towards the "greenification" of molecular imprinting technology (MIT) has already been initiated by the elaboration of green MIT principles; developing MIPs in a solvent-free environment may not only offer an eco-friendly alternative, but could also significantly influence the affinity and expected selectivity of the resulting binding sites. In the current study the first solvent-free mechanochemical synthesis of MIPs via liquid-assisted grinding (LAG) is reported. The successful synthesis of the imprinted polymer was functionally demonstrated by measuring its template rebinding capacity and the selectivity of the molecular recognition process in comparison with the ones obtained by the conventional, non-covalent molecular imprinting process in liquid media. The results demonstrated similar binding capacities towards the template molecule and superior chemoselectivity compared to the solution-based MIP synthesis method. The adoption of green chemistry principles with all their inherent advantages in the synthesis of MIPs may not only be able to alleviate the potential environmental and health concerns associated with their analytical (e.g., selective adsorbents) and biomedical (e.g., drug carriers or reservoirs) applications, but might also offer a conceptual change in molecular imprinting technology.