Polymeric nanoparticles for selective protein recognition by using thiol-ene miniemulsion photopolymerization

The fabrication of molecularly imprinted nanoparticles (MIP-NPs) specific for myoglobin by using thiol-ene photopolymerization in miniemulsion was described. Allyl derivatives of phenylalanine as a functional monomer was synthesized and copolymerized with acrylic monomers via miniemulsion polymerization to produce NIP-NPs with approximately 74 nm number average particle diameter. FTIR and ¹H-NMR analysis confirmed the synthesis of functional monomer. MIP-NPs were prepared in the existence of myoglobin as a template protein. Morphological investigations exhibited that the particle size of the MIP-NPs, increased compared to the corresponding NIPs and the mean particle diameter by number was measured as 141 nm with narrow distribution. NIP-NPs that were polymerized without myoglobin were found to have less affinity to the target protein. In addition, the rebinding ability of MIP-NPs was much bigger than that of the corresponding NIPs. ELISA results showed that MIPs interact particularly with the myoglobin and show little affinity for BSA in competitive binding experiments.HighlightsAllyl N,N-diallyl phenylalaninate was synthesized as a functional monomer.Imprinted nanoparticles were prepared by using thiol-ene photopolymerization in miniemulsion.The nanoparticles were 141 nm with narrow size distribution.The imprinted nanoparticles showed selectivity toward myoglobin.

Selective extraction and detection of β-agonists in swine urine for monitoring illegal use in livestock breeding

The illegal use of β-agonists often endangers animal-derived food safety. In this study, a selective detection method for β-agonists in swine urine was established via the combination of polymeric ionic liquid-molecularly imprinted graphene oxide-miniaturized pipette tip solid-phase extraction and high-performance liquid chromatography. It is worth noting that this method relied mainly on the designed adsorbent, which presented a rich adsorption mechanism, fast mass transfer rate, and high selectivity, and was successfully utilized in the selective extraction of β-agonists from swine urine samples. The proposed method has low LOD (0.20-0.56 ng/mL), high recovery (94.9-107.9%), and high reusability (4 times, 91.9-108.8%), which indicates its high potential as a selective, sensitive, accurate, and nonfatal method for monitoring the illegal use of β-agonists in the livestock breeding stage.

Evaluation of Surface Structure of Escherichia coli Using Polypyrrole Matrix

We propose a method to evaluate the surface structure of Escherichia coli focusing on the doping state of bacterial cells into polypyrrole (PPy) matrix. We found that the orientation of doping states of E. coli O rough was different from those of other serotypes of E. coli cells, which had O-antigen on their outer membrane. The results indicated that more than seventy percent of E. coli cells having O-antigen was horizontally doped into PPy matrix based on the chemical structure and the placement of O-antigen. On the other hand, the percentage for horizontal doping state of E. coli O rough cells was only approximately fifty percent. Moreover, the cells of each E. coli serotypes were specifically bound to their own shape-complementary cavities on the microspheres, but the binding affinity of E. coli O rough was a bit lower than that of other serotypes.

Molecularly Imprinted Polymers for Gossypol via Sol⁻Gel, Bulk, and Surface Layer Imprinting-A Comparative Study

Three gossypol molecularly imprinted polymers (MIPs) were prepared by bulk polymerization (MIP1), surface layer imprinting using silica gel as the support (MIP2), and the sol-gel process (MIP3). The as-prepared MIPs were characterized by SEM and nitrogen adsorption-desorption techniques to study the morphology structure. The adsorption experiments exhibited that MIP1 had adsorption capacity as high as 564 mg·g-1. The MIP2 showed faster adsorption kinetics than MIP1 and MIP3. The adsorption equilibrium could be reached for gossypol in 40 min. A selectivity study showed that the adsorption capacity of MIPs for gossypol was about 1.9 times higher than that of the structurally-similar analogs ellagic acid and 6.6 times higher than that of the quercetin. It was found that the pseudo-second-order kinetic model and the Freundlich isotherm model were more applicable for the adsorption kinetics and adsorption isotherm of gossypol binding onto the MIP1 and MIP2, respectively. Results suggested that among those three, the MIP2 was a desirable sorbent for rapid adsorption and MIP1 was suitable for selective recognition of gossypol.

Nanoporous imprinted polymers (nanoMIPs) for controlled release of cancer drug

In this article, a new approach to directly synthesize drug molecule imbedded in the nanometer sized polymer particles is reported. Molecular imprinting is used to prepare polymers for drug specific for selectively loading of a desired drug. Computer simulations were performed to provide mechanistic insights on the binding modalities of model cancer drug, amygdalin with the polymer precursors. Controlled release of amygdalin from nanoMIPs was studied in vitro cell test and monitoring the absorbance at λ_em of 390 nm by fluorescence. The nanoparticles imprinted with amygdalin (nanoMIPs) showed high drug loading (0.98 mg g^-1) and also releases drug in a controlled way without burst release. The polymer releases amygdalin 0.095 μg (5 min), 0.120 μg (30 min), 0.180 μg (180 min), 0.205 μg in 300 min in de-ionized water and similar pattern of release was observed in buffer 2 and 7. The sustained release of drug from nanoMIPs follows Fickian diffusion; and uniformity in nanoMIPs size have significant impact on release of drug. Swelling of nanoMIP is one of the dominant factors influencing the drug release patterns. The imprinting procedure and the studies reported in this study would be highly useful in future for cancer drug administration.

A versatile signal-enhanced ECL sensing platform based on molecular imprinting technique via PET-RAFT cross-linking polymerization using bifunctional ruthenium complex as both catalyst and sensing probes

Molecularly imprinted technique (MIT) has proven to be a significant tool in the analyzing area in virtue of its obvious advantages such as specific recognition, favorable stability to high temperature and higher sensitivity. Electrochemiluminescence (ECL) technology has also been receiving enormous attention as a powerful tool in sensing fields. However, sensors based on the combination of MIT and ECL technologies have seldom been reported yet. Herein, we find that Ru(bpy)₃²⁺ cannot only work as an efficient catalyst for photo-induced electron transfer-reversible addition-fragmentation chain transfer (PET-RAFT) polymerization, but also as a sensing probe for ECL sensor. Based on this, we successfully construct ECL sensors via the combination of MIT and ECL techniques. In details, poly(methacrylic acid) (PMAA) and cross-linked PMAA were synthesized first via a well-controlled PET-RAFT polymerization using Ru(bpy)₃²⁺ as catalyst under illumination of visible light with a wavelength of 460 nm, as confirmed by ¹H NMR and gel permeation chromatography (GPC). Then, negatively-charged Au nanoparticles (AuNPs) with average sizes of 20 nm were prepared and modified with Ru(bpy)₃²⁺ via electrostatic incorporation. MIPs were prepared on the surface of AuNPs using melamine (MEL) as the template via PET-RAFT controlled cross-linking polymerization. The MIPs modified AuNPs (AuNPs-MIPs) were then fixed on the surface of working electrode with Nafion to achieve a solid-state ECL sensing platform employing Ru(bpy)₃²⁺ as the ECL probes. The as-prepared sensor showed a wide detection range of 5.0 × 10^-13 - 5.0 × 10^-6 mol/L and a low detection limit of 1.0 × 10^-13 mol/L (S/N ≥ 3) was reached in the detection of MEL. Moreover, further tests for analyzing MEL structural analogues proved that the constructed ECL sensing platform could be utilized to detect various substances via specific recognitions.

Halloysite nanotubes in analytical sciences and in drug delivery: A review

Halloysite (HNT) is a natural inorganic mineral that has many applications in manufacturing. This review (with 192 references) covers (a) the chemical properties of halloysites, (b) the effects of alkali and acid etching on the loading capacity and the release behavior of halloysites, (c) the use of halloysite nanotubes in analytical sciences and drug delivery, and (d) recent trends in the preparation of magnetic HNTs. Synthetic methods such as co-precipitation, thermal decomposition, and solvothermal method are discussed, with emphasis on optimal magnetization. In the analytical field, recent advancements are summarized in terms of applications of HNT-nanocomposites for extraction and detection of heavy metal ions, dyes, organic pollutants, and biomolecules. The review also covers methods for synthesizing molecularly imprinted polymer-modified HNTs and magnetic HNTs. With respect to drug delivery, the toxicity, techniques for drug loading and the various classes of drug-halloysite nanocomposites are discussed. This review gives a general insight on the utilization of HNT in analytical determination and drug delivery systems which may be useful for researchers to generate new ideas. Graphical abstract Schematic presentation of the structure of halloysite nanotubes, selected examples of modifications and functionalization, and represetative field of applications.

Hybrid mesoporous organosilicas with molecularly imprinted cavities: towards extended exposure of active amino groups in the framework wall

Towards extended exposure of active sites in the framework of ordered mesoporous materials via molecularly imprinted cavities.

Preparation of a surface-grafted imprinted ceramic membrane for selective separation of molybdate anion from water solutions

A surface-grafted imprinted ceramic membrane (IIP-PVI/CM) for recognizing molybdate (Mo(VI)) anion was prepared by surface-initiated graft-polymerization. Firstly, raw alumina ceramic membrane (CM) was deposited with SiO₂ active layer by situ hydrolysis deposition method. Subsequently, γ-methacryloxy propyl trimethoxyl silane (MPS) was used as a coupling agent to introduce double bonds onto the SiO₂ layer (MPS-CM). Then, 1-vinylimidazole (VI) was employed as a functional monomer to graft-polymerization onto the MPS-CM (PVI-CM). During the graft-polymerization, the influence factors of grafting degree of PVI were investigated in detail. Under optimum conditions (monomer concentration 20wt%, temperature 70°C, initiator amount 1.1wt% and reaction time 8h), the grafting degree of 20.39g/100g was obtained. Further, Mo(VI) anion was used as a template to imprint in the PVI-CM by employing 1,6-dibromohexane as a cross-linking agent, and then Mo(VI) was removed, obtaining the IIP-PVI/CM with many imprinted cavities for Mo(VI). Thereafter, static adsorption and dynamic separation properties of IIP-PVI/CM for Mo(VI) were studied. Results indicate that IIP-PVI/CM shows a specific selectivity for Mo(VI) with the adsorption capacity of 0.69mmol/100g, and the selectivity coefficient of IIP-PVI/CM is 7.48 for molybdate to tungstate anions. During the dynamic separation, IIP-PVI/CM has also good selectivity for separation of Mo(VI) and W(VI) anions.

A Novel Sensitive Luminescence Probe Microspheres for Rapid and Efficient Detection of τ-Fluvalinate in Taihu Lake

Fluorescent molecularly imprinted polymers have shown great promise in biological or chemical separations and detection, due to their high stability, selectivity and sensitivity. In this work, fluorescent molecularly imprinted microsphere was synthesized via precipitation polymerization, which could separate efficiently and rapidly detect τ-fluvalinate (a toxic insecticide) in water samples, was reported. The fluorescent imprinted sensor showed excellent stability, outstanding selectivity and the limit of detection low to 12.14 nM, good regeneration ability which still kept good sensitivity after 8 cycling experiments and fluorescence quenching mechanism was illustrated in details. In addition, the fluorescent sensor was further used to detect τ-fluvalinate in real samples from Taihu Lake. Despite the relatively complex components of the environment water, the fluorescent imprinted microspheres sitll showed good recovery, clearly demonstrating the potental value of this smart sensor nanomaterial in environment monitoring.

Hydrophilic surface molecularly imprinted naringin prepared via reverse atom transfer radical polymerization with excellent recognition ability in a pure aqueous phase

An easy and highly efficient method using hydrophilic surface molecularly imprinted polymers (SMIPs) for the selective recognition of naringin from pure aqueous solution was developed.

A magnetic fluorescence molecularly imprinted polymer sensor with selectivity for dibutyl phthalate via Mn doped ZnS quantum dots

In this work, magnetic quantum dots molecularly imprinted polymers were synthesized, which were based on ZnS and magnetic Fe₃O₄.

Molecularly Imprinted Polymers for the Identification and Separation of Chiral Drugs and Biomolecules

Molecularly imprinting polymers (MIPs) have been extensively applied in chromatography for the separation of chiral drugs. In this review, we mainly summarize recent developments of various MIPs used as chiral stationary phases (CSPs) in high performance liquid chromatography (HPLC), capillary electrochromatography (CEC), and supercritical fluid chromatography (SFC). Among them, HPLC has the advantages of straightforward operation and high selectivity. However, the low separation efficiency, due to slow interaction kinetics and heavy peak broadening, is the main challenge for the application of MIPs in HPLC. On the other hand, CEC possesses both the high selectivity of HPLC and the high efficiency of capillary electrophoresis. In CEC, electroosmotic flow is formed across the entire column and reduces the heavy peak broadening observed in HPLC mode. SFC can modify the low interaction kinetics in HPLC when supercritical fluids are utilized as mobile phases. If SFC and MIP-based CSPs can be well combined, better separation performance can be achieved. Particles, monoliths and membrane are typical formats of MIPs. Traditional MIP particles produced by bulk polymerization have been replaced by MIP particles by surface imprinting technology, which are highly consistent in size and shape. Monolithic MIPs are prepared by in situ method in a column, greatly shortening the pre-preparation time. Some novel materials, such as magnetic nanoparticles, are integrated into the MIPs to enhance the controllability and efficiency of the polymerization. This review will be helpful to guide the preparation, development, and application of MIPs in chromatographic and electrophoretic enantioseparation.

Synthesis of core–shell imprinting polymers with uniform thin imprinting layer via iniferter-induced radical polymerization for the selective recognition of thymopentin in aqueous solution

Core–shell imprinting microspheres for the selective and rapid recognition of thymopentin with the aid of a novel polymeric ionic liquid.

A new simple extraction method for the extraction of hesperitin from wastewater

The HES-MMIPs presented good extraction activity, selection and reusability in the extraction of hesperitin from wastewater.

Well-defined nanostructured surface-imprinted polymers for the highly selective enrichment of low-abundance protein in mammalian cell extract

A new approach for the adsorption and enrichment of natural low-abundance protein by using nanostructured surface-imprinted polymers is presented.

Synthesis and evaluation of a molecularly imprinted polymer with high-efficiency recognition for dibutyl phthalate based on Mn-doped ZnS quantum dots

Molecularly imprinted polymers with Mn-doped ZnS quantum dots were prepared using dibutyl phthalate as the template molecule, 3-aminopropyltriethoxysilane as the functional monomer and the tetraethoxysilane as the cross-linker.

A novel molecularly imprinted polymer thin film at surface of ZnO nanorods for selective fluorescence detection of para-nitrophenol

A novel MIPs-based ZnO nanorods with molecular recognition ability for para-nitrophenol was successfully synthesized via a surface imprinting-directing polymerization.

Molecularly imprinted polymer nanospheres based on Mn-doped ZnS QDs via precipitation polymerization for room-temperature phosphorescence probing of 2,6-dichlorophenol

A novel MIPs-based RTP QDs with molecular recognition ability for 2,6-dichlorophenol was successfully synthesized via precipitation polymerization.

Preparation of core–shell ion imprinted nanoparticles via photoinitiated polymerization at ambient temperature for dynamic removal of cobalt in aqueous solution

In this work, novel core–shell ion imprinted polymers were firstly synthesized by photoinitiated polymerization (P-IIPs) for the selective separation of Co(ii) in aqueous solution.

Swelling technique inspired synthesis of a fluorescent composite sensor for highly selective detection of bifenthrin

A novel fluorescent imprinted sensor based on aqueous quantum dots (QDs) was prepared via a facile and versatile swelling technique for highly selective detection of bifenthrin.

A porous hybrid imprinted membrane for selectively anchoring target proteins from a complex matrix

The proposed route for the polymerization of CP/CNT/DA-MIM (A) and the recognition protocol of CP/CNT/DA-MIM (B).

Mesoporous molecularly imprinted polymer nanoparticles as a sustained release system of azithromycin

A combination of a molecular imprinting technique and precipitation polymerization was applied to develop novel azithromycin-imprinted poly(methacrylic acid-co-ethylene glycol dimethacrylate) nanoparticles for sustained release of azithromycin (AZM).

Template size matched film thickness for effectively in situ surface imprinting: a model study of glycoprotein imprints

For achieving a high imprinting efficiency, the film thickness should be compatible with the geometric size of fixed templates.

A facile one-pot synthesis of l-DOPA imprinted silica nanospheres for chiral separation and in vitro controlled release

A facile one-pot synthesis of l-DOPA imprinted silica nanospheres for chiral separation and in vitro controlled release.

Molecular imprinting science and technology: a survey of the literature for the years 2004-2011

Herein, we present a survey of the literature covering the development of molecular imprinting science and technology over the years 2004-2011. In total, 3779 references to the original papers, reviews, edited volumes and monographs from this period are included, along with recently identified uncited materials from prior to 2004, which were omitted in the first instalment of this series covering the years 1930-2003. In the presentation of the assembled references, a section presenting reviews and monographs covering the area is followed by sections describing fundamental aspects of molecular imprinting including the development of novel polymer formats. Thereafter, literature describing efforts to apply these polymeric materials to a range of application areas is presented. Current trends and areas of rapid development are discussed.