Interfacial Molecular Imprinting in Nanoparticle-Stabilized Emulsions

Computational design and preparation of water-compatible noncovalent imprinted microspheres

Herein, 2,4-dichlorophenoxyacetic acid (2,4-D) was used as a model template in a rational design strategy to produce water-compatible noncovalent imprinted microspheres. The proposed approach involved computational modelling for screening functional monomers and a simple method for preparing monodisperse and highly cross-linked microspheres. The fabricated non-imprinted polymer (NIP) and 2,4-d-imprinted polymer (2,4-d-MIP) were characterised, and their adsorption capabilities in an aqueous environment were evaluated. Results reveal that the pseudo-second-order kinetics model was appropriate for representing the adsorption of 2,4-D on NIP and 2,4-d-MIP, with R2 values of 0.97 and 0.99, respectively. The amount of 2,4-D adsorbed on 2,4-d-MIP (97.75 mg g-1) was considerably higher than those of phenoxyacetic acid (35.77 mg g-1), chlorogenic acid (9.72 mg g-1), spiramycin (1.56 mg g-1) and tylosin (1.67 mg g-1). Furthermore, it exhibited strong resistance to protein adsorption in an aqueous medium. These findings confirmed the feasibility of the proposed approach, providing a reference for the development of water-compatible noncovalent imprinted polymers.

Molecularly Imprinted Polymers Using Yeast as a Supporting Substrate

Molecularly imprinted polymers (MIPs) have gained significant attention as artificial receptors due to their low cost, mild operating conditions, and excellent selectivity. To optimize the synthesis process and enhance the recognition performance, various support materials for molecular imprinting have been explored as a crucial research direction. Yeast, a biological material, offers advantages such as being green and environmentally friendly, low cost, and easy availability, making it a promising supporting substrate in the molecular imprinting process. We focus on the preparation of different types of MIPs involving yeast and elaborate on the specific roles it plays in each case. Additionally, we discuss the advantages and limitations of yeast in the preparation of MIPs and conclude with the challenges and future development trends of yeast in molecular imprinting research.

Biodegradable and Sustainable Synthetic Antibodies-A Perspective

Molecular imprinting technology has been around for almost a century, and we have witnessed dramatic advancements in the overall design and production of molecularly imprinted polymers (MIPs), particularly in terms of possible formats of the final products when it comes to truly resembling antibody substitutes, i.e., MIP nanoparticles (MIP NPs). Nonetheless, the overall technology appears to struggle to keep up with the current global sustainability efforts, as recently elucidated in the latest comprehensive reviews, which introduced the "GREENIFICATION" concept. In this review, we will try to elucidate if these advancements in MIP nanotechnology have indeed resulted in a sustainability amelioration. We will do so by discussing the general production and purification strategies for MIP NPs, specifically from a sustainability and biodegradation perspective, also considering the final intended application and ultimate waste management.

Controlled synthesis of open-mouthed epitope-imprinted polymer nanocapsules with a PEGylated nanocore and their application for fluorescence detection of target protein

Epitope imprinting is an effective way to create artificial receptors for protein recognition. Surface imprinting with immobilized templates and sacrificial supports can generate high-quality imprinted cavities of homogeneous orientation and good accessibility, but it is still challenging to fabricate nanoscale imprinted materials by this approach. Herein, we propose a method for the controlled synthesis of open-mouthed epitope-imprinted polymer nanocapsules (OM-MIP NCs) by limiting the imprinting polymerization on the template-bearing side of the Janus nanoparticles (JNPs). Concurrent bromoacetyl (Ac–Br) and 2-bromoisobutyryl (iB–Br) functionalization of the major portion of SiO₂ nanoparticles is achieved via the molten-wax-in-water Pickering emulsion approach. The cysteinyl-derived epitope templates are immobilized through the Ac–Br groups, and then surface imprinting is fulfilled via ATRP initiated by the iB–Br groups. The SiO₂ supports are partially etched and then PEGlated, affording OM-MIP NCs with a PEGylated nanocore. The inside nanocore can facilitate collection of the NCs by centrifugation, and its PEGylation can inhibit non-specific binding. The surface imprinting can be optimized through the ATRP time, and the etching can be tailored via the concentration of NH₄HF₂ employed. For proof-of-concept, with a C-terminus nonapeptide of bovine serum albumin (BSA) chosen as a model epitope and polymerizable carbon dots added to the pre-polymerization solution, fluorescent OM-MIP NCs were fabricated for BSA sensing. The as-synthesized NCs exhibited satisfactory detection performance, with an imprinting factor of 6.1, a limit of detection of 38.1 nM, a linear range of 0.25–6 μM, and recoveries of 98.0 to 104.0% in bovine serum samples.

Surface epitope imprinting over the one side of Janus SiO₂ NPs via ATRP affords open-mouthed epitope-imprinted nanocapsules with imprinted cavities of homogeneous orientation and good accessibility for fluorescence detection of target protein.

Fabrication of highly crosslinked and monodispersed silicon-containing polymeric microspheres via photo-initiated polymerization and their application in capillary liquid chromatography

Although inorganic silica-based and polymeric micron-sized spheres have widely been explored as column packing materials in high performance liquid chromatography (HPLC), they are still suffering the problems of either alkali corrosion of silica or polymer swelling. It is still necessary to search simple approaches for fabrication of monodisperse micron-sized hybrid particles as packing materials in HPLC. A novel kind of silicon-containing polyacrylate microspheres was designed and fabricated via two-step swelling and photo-initiated polymerization approach using 3-(allylpropylsilane) propyl acrylate (TAPA) containing both acrylate and vinyl groups and trimethylolpropane triacrylate (TRIM) as precursors. After carefully optimizing the fabrication conditions, the monodisperse micron-sized microspheres could be acquired as chromatographic packing, exhibiting excellent mechanical stability and reproducibility. Due to existence of electron-rich vinyl groups, three kinds of thiols such as octadecanethiol (ODT), dithiothreitol (DTT) and trimethylolpropane tris(3-mercaptopropionate) (TTMP) were facilely anchored onto the surface of microsphere via photo-initiated thiol-ene click reaction. They were applied in the separation of small molecules by cLC-UV and complex biosamples by cLC-MS/MS. A total of 6691 unique peptides from 1771 unique proteins was identified by ODT-modified microsphere, which was higher than those by unmodified and DTT/TTMP-modified poly(TAPA-co-TRIM) microspheres. It was expected this kind of hybrid microspheres can be further modified and widely applied in chromatographic field, offering great potential in commercialization.

Direct Pore-Level Visualization and Verification of In Situ Oil-in-Water Pickering Emulsification during Polymeric Nanogel Flooding for EOR in a Transparent Three-Dimensional Micromodel

Different from inorganic nanoparticles, nanosized cross-linked polymeric nanoparticles (nanogels) have been demonstrated to generate more stable Pickering emulsions under harsh conditions for a long term owing to their inherent high hydrophilicity and surface energy. In both core and pore scales, the emulsions are found to be able to form in situ during the nanofluid flooding process for an enhanced oil recovery (EOR) process. Due to the limitation of direct visualization in core scale or deficient pore geometries built by two-dimensional micromodels, the in situ emulsification by nanofluids and emulsion transport are still not being well understood. In this work, we use a three-dimensional transparent porous medium to directly visualize the in situ emulsification during the nanogel flooding process for EOR after water flooding. By synthesizing the nanogel with a fluorescent dye, we find the nanogels adsorbed on the oil-water interface to lower the total interfacial energy and emulsify the large oil droplets into small Pickering oil-in-water emulsions. A potential mechanism for in situ emulsification by nanogels is proposed and discussed. After nanogel flooding, the emulsions trapped in pore throats and those in the effluents are all found encapsulated by the nanogels. After nanogel flooding under different flow rates, the sphericity and diameter changes of remaining oil droplets are quantitatively compared and analyzed using grouped boxplots. It is concluded that in situ emulsification happens during nanogel injection due to the reduction of interfacial tension, which helps to increase the oil recovery rate under different flow rates and pore geometries.

Fighting Antibiotic-Resistant Bacteria : Promising Strategies Orchestrated by Molecularly Imprinted Polymers

Infections caused by antibiotic-resistant bacteria are difficult and sometimes impossible to treat, making them one of the major public health problems of our time. We highlight how one unique material , molecularly imprinted polymers (MIPs), can orchestrate several strategies to fight this major societal issue. MIPs are tailor-made biomimetic supramolecular receptors that recognize and bind target molecules with a high affinity and selectivity, comparable to those of antibodies. While research on MIPs for combatting cancer has been constantly flourishing, comprehensive work on their involvement in combatting resistant superbugs has been rather scarce. This review aims at filling this gap. We will describe what are the causes of bacterial resistance and at which level MIPs can deploy their weapons. MIPs' targets can be biofilm constituents, quorum sensing messengers, bacterial surface proteins and antibiotic-deactivating enzymes, among others. We will conclude on the current challenges and future developments in this field.

Novel molecularly imprinted malachite green bifunctional imprinted microspheres through Pickering emulsion polymerization

The molecular imprinting process and solid particles confer MIP-MGs with excellent selective recognition and strong synergy of adsorption-photocatalysis towards MG removal.

Microsphere Polymers in Molecular Imprinting: Current and Future Perspectives

Molecularly imprinted polymers (MIPs) are specific crosslinked polymers that exhibit binding sites for template molecules. MIPs have been developed in various application areas of biology and chemistry; however, MIPs have some problems, including an irregular material shape. In recent years, studies have been conducted to overcome this drawback, with the synthesis of uniform microsphere MIPs or molecularly imprinted microspheres (MIMs). The polymer microsphere is limited to a minimum size of 5 nm and a molecular weight of 10,000 Da. This review describes the methods used to produce MIMs, such as precipitation polymerisation, controlled/'Living' radical precipitation polymerisation (CRPP), Pickering emulsion polymerisation and suspension polymerisation. In addition, some green chemistry aspects and future perspectives will also be given.

Artificial Cytochrome c Mimics: Graphene Oxide-Fe(III) Complex-Coated Molecularly Imprinted Colloidosomes for Selective Photoreduction of Highly Toxic Pollutants

Our previous works showed that the molecularly imprinted TiO₂ photocatalyst has been one of the most efficient materials for selective photooxidation of highly toxic organic pollutants (HTOPs) from complicated wastewater. However, some highly toxic pollutants (e.g., heavy metals) are very stable under the oxidizing environment. Therefore, the design of enzyme-like catalysts to selectively reduce highly toxic pollutants is extremely needed. In this work, inspired by the bioreduction ability of cytochrome c (cyt c, a heme containing metalloprotein), we presented a simple and efficient way to generate an artificial cyt c mimic (ACM) using graphene oxide (GO)-Fe(III) complex-coated molecularly imprinted colloidosomes. Prior to loading of Fe(III) centers to GO for constructing ACMs, GO-coated molecularly imprinted colloidosomes were synthesized via Pickering emulsion polymerization. Similar to a nature cyt c, the ACM contained both the molecular recognition element (molecularly imprinted cavity) and the non-heme electron sink (GO-Fe(III) complex), which resulted in the ACMs having good selectivity toward the enzyme-like reduction of the highly toxic target Cr(VI). Moreover, by using HepG2 cells as model cells, the Cr(VI) solution after treating by ACMs was proved to be safe and nontoxic. To confirm that the present method was universal for constructing ACMs, various GO-Fe(III) complex-coated molecularly imprinted colloidosomes, which could selectively photoreduce other highly toxic inorganic ions and organic pollutants, were also investigated. The ACMs described herein will act as a vector that encourages the design of more functional non-heme enzymes in sensing, environmental separation, clinical diagnose, and delivery of therapeutic agents.

Synthesis of molecularly imprinted polymers using a functionalized initiator for chiral-selective recognition of propranolol

We present a new concept of synthesis for preparation of molecularly imprinted polymers using a functionalized initiator to replace the traditional functional monomer. Using propranolol as a model template, a carboxyl-functionalized radical initiator was demonstrated to lead to high-selectivity polymer particles prepared in a standard precipitation polymerization system. When a single enantiomer of propranolol was used as template, the imprinted polymer particles exhibited clear chiral selectivity in an equilibrium binding experiment. Unlike the previous molecular imprinting systems where the active free radicals can be distant from the template-functional monomer complex, the method reported in this work makes sure that the actual radical polymerization takes place in the vicinity of the template-associated functional groups. The success of using functional initiator to synthesize molecularly imprinted polymers brings in new possibilities to improve the functional performance of molecularly imprinted synthetic receptors.

Epitope Imprinting Technology: Progress, Applications, and Perspectives toward Artificial Antibodies

Epitope imprinting is a promising tool to generate antibody-like specific recognition sites. Recently, because of the ease of obtaining templates, the flexibility in selecting monomers, their resistance to harsh environments, and the high specificity toward targets, epitope-imprinted materials have attracted much attention in various fields, such as bioanalysis, clinical therapy, and pharmacy. Here, the discussion is focused on the current representative epitope imprinting technologies, including epitope bulk imprinting and epitope surface imprinting. Moreover, the application of epitope-imprinted materials to the recognition of peptides, proteins, and cells is reviewed. Finally, the remaining challenges arising from the intrinsic properties of epitope imprinting are discussed, and future development in the field is prospected.

Effects of nano-confinement and conformational mobility on molecular imprinting of cross-linked micelles

Molecular imprinting is a facile method to create guest-complementary binding sites in a cross-linked polymeric network. When performed within cross-linked micelles, the resulting molecularly imprinted nanoparticles (MINPs) exhibited an extraordinary ability to distinguish subtle structural changes in the guest, including the shift of a hydrophilic or hydrophobic group by 1 carbon and addition of a single methylene/methyl group. A high surface-cross-linking density prior to core-cross-linking was key to the high-fidelity imprinting, enhancing both the binding affinity of the imprinted micelle for the template and selectivity among structural analogues. Whereas the imprinted site closely complemented the hydrophilic surface anchoring group and rigid hydrophobic aromatic core, it was expanded significantly for a conformationally mobile small group (i.e., methoxy).

Preparation of Fluorescent Molecularly Imprinted Polymers via Pickering Emulsion Interfaces and the Application for Visual Sensing Analysis of Listeria Monocytogenes

In this work, a novel molecularly imprinted polymer (MIP) with water-soluble CdTe quantum dots (QDs) was synthesized by oil-in-water Pickering emulsion polymerization using whole Listeria monocytogenes as the template. Listeria monocytogenes was first treated by acryloyl-functionalized chitosan with QDs to form a bacteria-chitosan network as the water phase. This was then stabilized in an oil-in-water emulsion comprising a cross-linker, monomer, and initiator, causing recognition sites on the surface of microspheres embedded with CdTe QDs. The resulting MIP microspheres enabled selective capture of the target bacteria via recognition cavities. The target bacteria Listeria monocytogenes was detected. Scanning electron microscopy (SEM) characterization showed that the MIPs had a rough spherical shape. There was visual fluorescence detection via quenching in the presence of the target molecule, which offered qualitative detection of Listeria monocytogenes in milk and pork samples. The developed method simplified the analysis process and did not require any sample pretreatment. In addition, the fluorescence sensor provided an effective, fast, and convenient method for Listeria monocytogenes detection in food samples.

Investigation of nanoparticle immobilized cellulase: nanoparticle identity, linker length and polyphenol hydrolysis

Cellulase containing nanobiocatalysts have been useful as an extraction tool based on their ability to disrupt plant cell walls. In this work, we investigate the effect of nanoparticle composition and chemical linkage towards immobilized cellulase activity. Cellulase nanoconstructs have been prepared, characterized and compared for their loading efficiencies with standard assays and enzyme kinetics and correlate well with the cognate loading efficiencies. Application of the cellulase-immobilized nanoparticles on onion skins results in release of a distinctive composition of polyphenols. The aglycosidic form of quercetin is the dominant product of onion skin hydrolysis affected by cellulase nanobiocatalysts. Chitosan-coated iron oxide nanoparticles with APTES-conjugated cellulase are found to be most effective for polyphenol release and for transformation of glycosidic to aglycosidic form of quercetin. These results shed light on the activity of immobilized cellulase beyond their role in cell wall disruption and are important for the practical application of cellulase nanobiocatalysts.

Molecularly imprinted polymers fabricated by Pickering emulsion polymerization for the selective adsorption and separation of quercetin from Spina Gleditsiae

Hydroxyapatite-stabilized Pickering emulsions and their application in the extraction of quercetin.

Preparation of Molecularly Imprinted Microspheres as Biomimetic Recognition Material for In Situ Adsorption and Selective Chemiluminescence Determination of Bisphenol A

Bisphenol A (BPA) is an endocrine disrupter in environments which can induce abnormal differentiation of reproductive organs by interfering with the action of endogenous gonadal steroid hormones. In this work, the bisphenol A (BPA) molecularly-imprinted microspheres (MIMS) were prepared and used as biomimetic recognition material for in situ adsorption and selective chemiluminescence (CL) determination of BPA. Through non-covalent interaction, the BPA-MIMS was successfully prepared by Pickering emulsion polymerization using a BPA template, 4-vinylpyridine (4-VP) monomer, ethylene glycol dimethacrylate (EGDMA) cross-linker, and a SiO₂ dispersion agent. The characterization of scanning electron microscopy (SEM) and energy-disperse spectroscopy (EDS) showed that the obtained MIMS possessed a regular spherical shape and narrow diameter distribution (25–30 μm). The binding experiment indicated BPA could be adsorbed in situ on the MIMS-packing cell with an apparent maximum amount Q_max of 677.3 μg g⁻¹. Then BPA could be selectively detected by its sensitive inhibition effect on the CL reaction between luminol and periodate (KIO₄), and the inhibition mechanism was discussed to reveal the CL reaction process. The CL intensity was linear to BPA concentrations in two ranges, respectively from 0.5 to 1.5 μg mL⁻¹ with a detection limit of 8.0 ng mL⁻¹ (3σ), and from 1.5 to 15 μg mL⁻¹ with a limit of detection (LOD) of 80 ng mL⁻¹ (3σ). The BPA-MIPMS showed excellent selectivity for BPA adsorption and the proposed CL method has been successfully applied to BPA determination in environmental water samples.

Polyaniline Nanofibers: Their Amphiphilicity and Uses for Pickering Emulsions and On-Demand Emulsion Separation

The wetting property of nanomaterials is of great importance to both fundamental understanding and potential applications. However, the study on the intrinsic wetting property of nanomaterials is interfered by organic capping agents, which are often used to lower the surface energy of nanomaterials and avoid their irreversible agglomeration. In this work, the wetting property of the nanostructured polyaniline that requires no organic capping agents is investigated. Compared to hydrophilic granular particulates, polyaniline nanofibers are amphiphilic and have an excellent capability of creating Pickering emulsions at a wide range of pH. It is suggested that polyaniline nanofibers can be easily wetted by water and oil. Furthermore, the amphiphilic polyaniline nanofibers as building blocks can be used to construct filtration membranes with a small pore size. The wetting layer of the continuous phase of emulsions in the porous nanochannels efficiently prevents the permeation of the dispersed phase, realizing high-efficiency on-demand emulsion separation.

A robust electrochemical sensing platform using carbon paste electrode modified with molecularly imprinted microsphere and its application on methyl parathion detection

A highly sensitive electrochemical sensor using a carbon paste electrode (CPE) modified with surface molecularly imprinted polymeric microspheres (SMIPMs) was developed for methyl parathion (MP) detection. Molecular imprinting technique based on distillation precipitation polymerization was applied to prepare SMIPMs and non-surface imprinted microspheres (MIPMs). The polymer properties including morphology, size distribution, BET specific surface area and adsorption performance were investigated and compared carefully. Both MIPMs and SMIPMs were adopted to prepare CPE sensors and their electrochemical behaviors were characterized via cyclic voltammetry and electrochemical impedance spectroscopy. Compared with MIPMs packed sensor, SMIPMs/CPE exhibits a higher sensing response towards MP with linear detection range of 1 × 10^-12-8 × 10^-9 mol L^-1 and detection limit of 3.4 × 10^-13 mol L^-1 (S/N = 3). Moreover, SMIPMs/CPE exhibits good selectivity and stability in multiple-cycle usage and after long-time storage. Finally, the developed sensor was used to determine MP in real samples including soil and vegetables and only simple pretreatment is needed. The detection results were consistent with those obtained from liquid chromatography. Collectively, this newly developed sensor system shows significant potential for use in a variety of fields like food safety, drug residue determination and environmental monitoring.

Fabrication of micron-sized BSA-imprinted polymers with outstanding adsorption capacity based on poly(glycidyl methacrylate)/polystyrene (PGMA/PS) anisotropic microspheres

Monodisperse poly(glycidyl methacrylate)/polystyrene (PGMA/PS) anisotropic microspheres have been fabricated by seed polymerization for BSA-imprinting microspheres.

Combining Pickering Emulsion Polymerization with Molecular Imprinting to Prepare Polymer Microspheres for Selective Solid-Phase Extraction of Malachite Green

Malachite green (MG) is currently posing a carcinogenic threat to the safety of human lives; therefore, it is highly desirable to develop an effective method for fast trace detection of MG. Herein, for the first time, this paper presents a systematic study on polymer microspheres, being prepared by combined Pickering emulsion polymerization and molecular imprinting, to detect and purify MG. The microspheres, molecularly imprinted with MG, show enhanced adsorption selectivity to MG, despite a somewhat lowered adsorption capacity, as compared to the counterpart without molecular imprinting. Structural features and adsorption performance of these microspheres are elucidated by different characterizations and kinetic and thermodynamic analyses. The surface of the molecularly imprinted polymer microspheres (M-PMs) exhibits regular pores of uniform pore size distribution, endowing M-PMs with impressive adsorption selectivity to MG. In contrast, the microspheres without molecular imprinting show a larger average particle diameter and an uneven porous surface (with roughness and a large pore size), causing a lower adsorption selectivity to MG despite a higher adsorption capacity. Various adsorption conditions are investigated, such as pH and initial concentration of the solution with MG, for optimizing the adsorption performance of M-PMs in selectively tackling MG. The adsorption kinetics and thermodynamics are deeply discussed and analyzed, so as to provide a full picture of the adsorption behaviors of the polymer microspheres with and without the molecular imprinting. Significantly, M-PMs show promising solid-phase extraction column applications for recovering MG in a continuous extraction manner.

Synthesis of naproxen-imprinted polymer using Pickering emulsion polymerization

For the last decades, molecular imprinting is developing intensively, especially in the case of the application of new imprinting techniques. In this work, for the first time, a Pickering emulsion polymerization was used to synthesize the S-naproxen-imprinted polymer spheres following a noncovalent protocol. To enhance the knowledge about imprinting process using mentioned technique, thorough analysis of the synthesis process was performed. Optimization of polymerization conditions included the selection of functional monomer, cross-linking agent, type of porogen, surfactant, and the choice of appropriate amount of the template and porogen. Prepared materials were characterized using scanning electron microscopy and nitrogen adsorption. To study the binding properties, the sorption studies, including adsorption isotherms and competitive binding, were performed. Investigation of the effect of the functional monomer on the selective recognition of S-naproxen showed that the interactions between the template molecule and 4-vinylpyridine resulted in the best recognizing ability. Moreover, the synthesis with application of ethylene glycol dimethacrylae as a cross-linker, toluene as a porogen, and Tween 20 as an additional emulsion stabilizer gave the most desired result. The optimal ratio of the porogen to monomers mixture was 0.1, due to the fact that the increase of the porogen volume resulted in the significant increase of nonspecific uptake. In addition, the tenfold molar excess of functional monomer relative to the template turned out to be optimal. Subsequent binding studies demonstrated that the material synthesized using optimized polymerization conditions consists of imprinted sites that are sensitive for the S-naproxen.

Generation of Janus Molecularly Imprinted Polymer Particles

Janus particles, which have two or more distinct physical surfaces, provide a number of potential applications in many fields. However, it is difficult to selectively load chemical or biological components onto the Janus particles. Here, the approach utilizing molecular imprinting and Pickering emulsion technologies for the synthesis of molecularly imprinted polymer (MIP)-based Janus particles (which showed high affinity to the targets) is described stepwise. As self-propelled microengines possessing specific molecular recognition ability, Janus molecularly imprinted polymer particles show high potential for specific and well-controlled drug delivery.

Catalytic Formation of Disulfide Bonds in Peptides by Molecularly Imprinted Microgels at Oil/Water Interfaces

This work describes the preparation and investigation of molecularly imprinted polymer (MIP) microgel (MG) stabilized Pickering emulsions (PEs) for their ability to catalyze the formation of disulfide bonds in peptides at the O/W interface. The MIP MGs were synthesized via precipitation polymerization and a programmed initiator change strategy. The MIP MGs were characterized using DLS analysis, SEM measurement, and optical microscopy analysis. The dry and wet MIP MGs showed a hydrodynamic diameter of 100 and 280 nm, respectively. A template rebinding experiment showed that the MIP MGs bound over two times more template (24 mg g^-1) compared to the uptake displayed by a nonimprinted reference polymer (NIP) MG (10 mg g^-1) at saturation. Using the MIP MGs as stabilizers, catalytic oxidation systems were prepared by emulsifying the oil phase and water phase in the presence of different oxidizing agents. During the cyclization, the isolation of the thiol precursors and the oxidizing reagents nonselectively decreased the formation of the byproducts, while the imprinted cavities on the MIP MGs selectively promoted the intramolecular cyclization of peptides. When I₂ was used as the oxidizing agent, the MIP-PE-I₂ system showed a product yield of 50%, corresponding to a nearly 2-fold increase compared to that of the nonimprinted polymer NIP-PE-I₂ system (26%). We believe the interfacial catalysis system presented in this work may offer significant benefits in synthetic peptide chemistry by raising productivity while suppressing the formation of byproducts.

Reflux precipitation polymerization: a new synthetic insight in molecular imprinting at high temperature

Reflux precipitation polymerization was first used to fabricate monodispersed MIP microspheres, indicating electrostatic interaction was important for molecular imprinting at high temperature.

Graphene oxide as a sacrificial material for fabricating molecularly imprinted polymers via Pickering emulsion polymerization

Graphene oxide (GO) was introduced as a sacrificial material, for the first time, to fabricate a hollow molecularly imprinted polymer (HMIP) via Pickering emulsion polymerization.

Bio-inspired magnetic molecularly imprinted polymers based on Pickering emulsions for selective protein recognition

Hydrophobic halloysite nanotube stabilized Pickering emulsions and their application in protein separation.

A modular approach for assembling turn-on fluorescence sensors using molecularly imprinted nanoparticles

Combining straightforward molecular imprinting with orthogonal click chemistry and accessible fluorescent dyes, a modular approach has been developed to assemble turn-on optical sensors based on fluorescence resonance energy transfer in molecularly imprinted nanoparticles.

Molecularly imprinted polymeric micro- and nano-particles for the targeted delivery of active molecules

Molecular imprinting (MI) represents a strategy to introduce a 'molecular memory' in a polymeric system obtaining materials with specific recognition properties. MI particles can be used as drug delivery systems providing a targeted release and thus reducing the side effects. The introduction of molecular recognition properties on a polymeric drug carrier represents a challenge in the development of targeted delivery systems to increase their efficiency. This review will summarize the limited number of drug delivery MI particles described in the literature along with an overview of potential solutions for a larger exploitation of MI particles as targeted drug delivery carriers. Molecularly imprinted drug carriers can be considered interesting candidates to significantly improve the efficiency of a controlled drug treatment.

Current and emerging lipid-based systems for transdermal drug delivery

Developing a transdermal drug delivery system is a challenging task considering the selective permeability of the skin and the physicochemical properties the drug must possess to permeate through the skin. Lipid-based drug delivery systems have contributed a great deal in this direction in the last few decades, and thereby have helped to expand the range of therapeutic molecules that can be delivered through the skin in a safe and effective manner. Additionally, vesicular delivery systems such as nanoparticles and emulsions have also played important roles in providing alternative novel approaches for drug delivery. In this article, we will discuss some of the current and future lipid-based systems for transdermal drug delivery along with the associated challenges.