Preparation of multi-walled carbon nanotubes based magnetic multi-template molecularly imprinted polymer for the adsorption of phthalate esters in water samples

Adsorption plasticizer by nanosphere adsorbent of persimmon tannin binding bovine serum protein

In this study, nanosphere (NS) of a persimmon tannin binding bovine serum protein (BSA-PT-NS) adsorbent were prepared. The BSA-PT-NS exhibited good adsorption capacity for the plasticizer diethyl phthalate (DEP), with an adsorption rate of 74.5 %. The BSA-PT-NSs were spherical and their surfaces appeared to be uneven. The FT-IR and XPS results indicated that the adsorption of DEP was mainly due to the phenol hydroxyl group on PT, and the CO and -NH- functional groups of BSA also contributed. The addition of Na+, Ca2+, and Mg2+ significantly decreased the adsorption rate (P < 0.05). The maximum DEP adsorption capacity of BSA-BT-NS was calculated to be 487.8 mg/g based on the Langmuir linear model. The adsorption kinetics results showed that the pseudo-first-order model fitted well. The DEP removal rate remained above 68 % after five cycles, demonstrating that the BSA-PT-NSs had excellent regeneration properties for DEP adsorption.

Recent advancements in the extraction and analysis of phthalate acid esters in food samples

Phthalate acid esters (PAEs) are ubiquitous environmental pollutants present in food samples, necessitating accurate detection for risk assessment and remediation efforts. This review provides an updated overview of the recent progress on the PAEs analysis regarding sample pretreatment techniques and analytical methodologies over the latest decade. Advances in sample preparation include solid-based extraction techniques replacing conventional liquid-liquid extraction, with solid sorbents emerging as promising alternatives due to their minimal solvent consumption and enhanced selectivity. Although techniques like the microextraction methods offer versatility and reduced solvent reliance, there is a need for more efficient and environmentally friendly techniques enabling on-site portable detection. High-resolution mass spectrometry is increasingly utilized for its enhanced sensitivity and reduced contamination risks. However, challenges persist in developing in situ analytical techniques for trace PAEs in complex food samples. Future research should prioritize novel analytical techniques with superior sensitivity and selectivity, addressing current limitations to meet the demand for precise PAEs detection in diverse food matrices.

Algae- and bacteria-based biodegradation of phthalic acid esters towards the sustainable green solution

Phthalic acid esters are widely used worldwide as plasticizers. The high consumption of phthalates in China makes it the world's largest plasticizer market. The lack of phthalic acid ester's chemical bonding with the polymer matrix facilitates their detachment from plastic products and subsequent release into the environment and causes serious threats to the health of living organisms. Thus, environmentally friendly and sustainable solutions for their removal are urgently needed. In this context, both natural and engineered bacterial and algal communities have played a crucial role in the degradation of various phthalic acid esters present in water and soil. When algae-bacteria co-culture is compared to a singular algae or bacteria system, this symbiotic system shows superior performance in the removal of dibutyl phthalates and diethyl phthalates from synthetic wastewater. This review provides an optimistic outlook for co-culture systems by in-depth examining single microorganisms, namely bacteria and algae, as well as algae-bacterial consortiums for phthalates degradation, which will draw attention to species co-existence for the removal of various pollutants from the environment. In addition, further development and research, particularly on the mechanisms, genes involved in the degradation of phthalic acid esters, and interactions between bacterial and algal species, will lead to the discovery of more adaptable species as well as the production of targeted species to address the environmental pollution crisis and provide a green, efficient, and sustainable approach to environmental protection. Discrepancies in knowledge and potential avenues for exploration will enhance the existing body of literature, enabling researchers to investigate this field more comprehensively.

Preparation of novel magnetic ethylene glycol dimethacrylate-based molecularly imprinted polymer for rapid adsorption of phthalate esters from ethanol aqueous solution

Phthalate esters (PAEs), as emerging pollutants, pose a serious threat to human health and have become a major concern in the fields of environmental protection and food safety. Selective adsorption using molecularly imprinted polymer (MIP) is feasible, but most MIPs use the potentially toxic methacrylic acid (MAA) as a functional monomer, along with other crosslinking agents. In this study, MIP adsorbent was prepared using only ethylene glycol dimethacrylate (EGDMA) as both the functional monomer and crosslinking agent, without the inclusion of MAA. The adsorbent was utilized for the adsorption of PAEs from an ethanol aqueous solution. The results showed that EGDMA-based MIP (EMIP) achieved better adsorption performance of PAEs than MAA-based MIP (MMIP) due to more interactions of EGDMA with PAEs than MAA with them. For the adsorption of dibutyl phthalate (DBP) using EMIP, 95% of the equilibrium adsorption capacity was achieved within the first 15 min. In the isotherm analysis, the theoretical maximum adsorption capacity of EMIP was obtained as high as 159.24 mg/g at 20 °C in an ethanol (10 v%) aqueous solution. Furthermore, the adsorption of EMIP was not affected by the pH of the solution. The adsorption process of EMIP followed the pseudo-second-order kinetic and Freundlich isotherm model. Ethanol had a significant impact on the adsorption of DBP, and the results of molecular simulation could validate this. In addition, the regeneration experiments indicated that EMIP could be recycled 5 times without significant performance change and had a high recovery efficiency of 94.55%.

Preparation of novel gallic acid-based dummy-template molecularly imprinted polymer adsorbents for rapid adsorption of dibutyl phthalate from water

Phthalate esters (PAEs) are plasticizers widely used in the industry and easily released into the environment, posing a serious threat to human health. Molecularly imprinted polymers (MIPs) are important as selective adsorbents for the removal of PAEs. In this study, three kinds of mussel-inspired MIPs for the removal of PAEs were first prepared with gallic acid (GA), hexanediamine (HD), tannic acid (TA), and dopamine (DA) under mild conditions. The adsorption results showed that the MIP with low cost derived from GA and HD (GAHD-MIP) obtained the highest adsorption capacity among these materials. Furthermore, 97.43% of equilibrium capacity could be reached within the first 5 min of adsorption. Especially, the dummy template of diallyl phthalate (DAP) with low toxicity was observed to be more suitable to prepare MIPs than dibutyl phthalate (DBP), although DBP was the target of adsorption. The adsorption process was in accordance with the pseudo-second-order kinetics model. In the isotherm analysis, the adsorption behavior agreed with the Freundlich model. Additionally, the material maintained high adsorption performance after 7 cycles of regeneration tests. The GAHD-MIP adsorbents in this study, with low cost, rapid adsorption equilibrium, green raw materials, and low toxicity dummy template, provide a valuable reference for the design and development of new MIPs.

An Updated Overview of Magnetic Composites for Water Decontamination

Water contamination by harmful organic and inorganic compounds seriously burdens human health and aquatic life. A series of conventional water purification methods can be employed, yet they come with certain disadvantages, including resulting sludge or solid waste, incomplete treatment process, and high costs. To overcome these limitations, attention has been drawn to nanotechnology for fabricating better-performing adsorbents for contaminant removal. In particular, magnetic nanostructures hold promise for water decontamination applications, benefiting from easy removal from aqueous solutions. In this respect, numerous researchers worldwide have reported incorporating magnetic particles into many composite materials. Therefore, this review aims to present the newest advancements in the field of magnetic composites for water decontamination, describing the appealing properties of a series of base materials and including the results of the most recent studies. In more detail, carbon-, polymer-, hydrogel-, aerogel-, silica-, clay-, biochar-, metal-organic framework-, and covalent organic framework-based magnetic composites are overviewed, which have displayed promising adsorption capacity for industrial pollutants.

A global meta-analysis of phthalate esters in drinking water sources and associated health risks

Phthalate esters (PAEs) are known as esters of phthalic acid, which are commonly used as plasticizers in the plastic industry. Due to the lack of chemical bonding with the polymer matrix, these compounds are easily separated from plastic products and enter the environment. To investigate the growth of concentration of PAEs like DBP (Dibutyl phthalate), DEP (Diethyl phthalate), DMP (Dimethyl phthalate), DIBP (Diisobutyl phthalate), and TPMBP (tris(2-methylbutyl) phosphate) in different water sources, a study from January 01, 1976, to April 30, 2021, was implemented via a global systematic review plus meta-analysis in which, 109 articles comprising 4061 samples, 4 water types, and 27 countries were included. Between various types of water sources, river water and lake water were the most contaminated resources with PAEs. Among all studies of PAEs, DBP and DEP with the values >15,573 mg L-1 have the highest average concentration and TPMBP with the value 0.002885 mg L-1 has the lowest average concentration in water sources. The most contaminated water sources with PAEs were in Nigeria and the least contaminated was in China. Besides, Monte-Carlo simulation indicated that for DMP and DEP minimum values that are lower than the acceptable limit are generated. However, most of the population (>75 %) is at risk for both adults and child cases. For DIBP and DBP the situation is much worse, the simulations not providing at least one case where the R index is lower than the acceptable limit of 1E-06.

Targeted degradation of naphthalene by peroxymonosulfate activation using molecularly imprinted biochar

Polycyclic aromatic hydrocarbons (PAHs) in aquatic environments are threatening ecosystems and human health. In this work, an effective and environmentally friendly catalyst based on biochar and molecular imprinting technology (MIT) was developed for the targeted degradation of PAHs by activating peroxymonosulfate. The results show that the adsorption amount of naphthalene (NAP) by molecularly imprinted biochar (MIP@BC) can reach 82% of the equilibrium adsorption capacity within 5 min, and it had well targeted adsorption for NAP in the solution mixture of NAP, QL and SMX. According to the comparison between the removal rates of NAP and QL by MIP@BC/PMS or BC/PMS system in respective pure solutions or mixed solutions, the MIP@BC/PMS system can better resist the interference of competing pollutants (i.e., QL) compared to the BC/PMS system; that is, MIP@BC had a good ability to selectively degrade NAP. Besides, the removal rate of NAP by MIP@BC/PMS gradually decreased as pH increased. The addition of Cl- greatly promoted the targeted removal of NAP in the MIP@BC/PMS system, while HCO3- and CO32- both had an inhibitory effect. Furthermore, SO4•-, O2•- and 1O2 produced by BC activating PMS dominated the NAP degradation, and it was inferred that the vacated imprinted cavities after NAP degradation can continue to selectively adsorb NAP and this could facilitate the reusability of the material. This study can promote the research on the targeted degradation of PAHs through the synergism of biochar/PMS advanced oxidation processes and MIT.

The erythromycin sorption removal at environmentally relevant concentration based on molecular imprinted polymer: Performance and mechanism

The antibiotic pollution emerged in different environments has raised a great concern. Adsorption is an effective method to solve the problem. However, conventional adsorbents are not always efficient for antibiotic removal with interferences. Therefore, in this study, molecularly imprinted polymer (EMIP) with selective adsorption ability was prepared to remove a typical antibiotic-erythromycin (ERY) at environmentally relevant concentration. The specific surface area of EMIP was 265.62 m2/g with large pore volume, small pore size and hydrophobic surface. The adsorption capacity of EMIP was increased from 211.08 to 4015.51 μg/g when the concentration of ERY was increased from 5.00 to 100.00 μg/L. The isothermal adsorption process was fitted well with the Langmuir model. The adsorption kinetic could be well described by the pseudo-second-order model. With co-existing of interferences, the imprinting factor for ERY was 2.57, which demonstrated EMIP had good adsorption selectivity. After five consecutive adsorption-desorption experiments, the adsorption capacity of EMIP was still over 80%. The results of molecular dynamic simulation showed the adsorption energy between ERY and EMIP was high, which was favorable for ERY adsorption removal. Hopefully, the results of this study could provide new insights for trace antibiotic removal by molecular imprinting polymers in different aqueous environments.

Novel electrochemical sensing platform basing on di-functional stimuli-responsive imprinted polymers for simultaneous extraction and determination of metronidazole

A novel magnetic-controlled electrochemical sensor has been fabricated by combined photo-responsive surface molecular imprinted polymers (P-SMIPs) and electrochemical sensor. In particular, the P-SMIPs were obtained by living radical polymerization of photo-responsive functional monomer onto the magnetic Fe₃O₄ modified multi-walled carbon nanotubes nanocomposites. The magnetic glassy carbon electrode was introduced to make the anchoring and removal of P-SMIPs onto the magnetic-controlled glassy carbon electrode easy to manipulate. Driven by UV/vis light, the platform performs releasing and absorption of metronidazole basing on conformational variations of the photo-responsive monomer at the receptor sites part in the P-SMIPs. This process can be tested by the photo-responsive variations of metronidazole electrochemical signal. As the consequence, extracting of P-SMIPs sensor can be conveniently triggered by the controllable UV light intervention measure, leading to effectively improve in both analytes mass transfer rate to the receiving media and extraction efficiency. The experimental result indicated that the excellent recoveries of metronidazole were varied between 77.9% and 89.9% with RSDs ≤4.87% in the biological samples. Therefore, the P-SMIPs sensor shows satisfactory potential in reusable extractions that can be recycled several times with no significant loss of activity, and this utilization strategy can be extended to other analytes, achieving manifold applications of pharmaceutical and environmental.

Nonlinear regression for treating adsorption isotherm data to characterize new sorbents: Advantages over linearization demonstrated with simulated and experimental data

This paper demonstrates that determining adsorption capacity and affinity through data fitting of adsorption isotherms by nonlinear regression (NLR) is more accurate than linearized Langmuir equations. Linearization errors and the subjective choice of data points used to apply the linear regression analysis may deviate the fitted adsorption parameters (constants and adsorption capacities) from the expected values. The deviation magnitude increases for heterogeneous sorbents such as environmental particles and molecularly imprinted polymers, which adsorb by more than one sorption mechanism or adsorption sites of diverse chemical natures. For instance, Lineweaver-Burk linearization of isotherms simulated considering the presence of two adsorption sites (distinct adsorption energies) provides excellent linear regression fittings but for only one kind of adsorption site. Contrary, Scatchard and Eadie-Hoffsiee's equations indicate the presence of more than one kind of adsorption site, but if the difference between the adsorption constants is not significant, the choice of points used to perform the computation becomes subjective. On the contrary, NLR analysis considers all the adsorption points (experimental or simulated), providing objective criteria to define if more than one kind of site or retention mechanism rules the adsorbed amounts of analyte. The fitted constants have smaller deviations from the expected values than those obtained by linearization. In addition to the simulated data, the enhanced robustness of the NLR was demonstrated in the determination of the adsorption capacity and adsorption affinity of a humic acid sample towards Cu²⁺ at different pH.

A multi-site recognition molecularly imprinted solid-phase microextraction fiber for selective enrichment of three cross-class environmental endocrine disruptors

Molecularly imprinted solid-phase microextraction fibers with multi-site recognition were prepared for the simultaneous enrichment of three cross-class environmental endocrine disruptors (EEDs) in environmental water. The surface morphology of the multi-site recognition molecularly imprinted fibers was characterized using scanning electron microscopy, atomic force microscopy, Fourier transform infrared spectroscopy, and surface area and pore size analyzer. Under optimal extraction conditions, the molecularly imprinted fibers showed higher extraction capacity to bisphenol F, diethyl phthalate, and methyl paraben than non-imprinted polymer fibers and commercial fibers. Compared with commercial solid-phase microextraction fibers, the multi-site recognition molecularly imprinted fibers showed superior extraction performance at different concentrations of analytes. The selectivity study confirmed that the multi-site recognition molecularly imprinted solid-phase microextraction fibers were highly selective not only for specific template molecules but also for bisphenols, parabens, and phthalates. Furthermore, the method achieved a limit of detection of 0.003-0.02 μg L^-1 for the three cross-class EEDs in environmental water samples with recoveries ranging from 75.76% to 112.69% and relative standard deviations below 11.46%. Thus, the novel MIP fibers with multi-site recognition prepared in this work have provided a promising approach in the field of specific adsorption and a strategy for the simultaneous and sensitive monitoring of multiple cross-class trace EEDs.

Coassisted carbonization with HCOOK/(HCOO)2Ca for the fabrication of bamboo-derived oxygen-doped porous carbons exhibiting high-performance sorption of diethyl phthalate from aqueous solutions

Porous carbons are excellent sorbents for removing organic pollutants. Green conversion of biowaste into advanced porous carbons is crucial for industrialized production and practical applications, which, however, have rarely been investigated. This study develops a coassisted carbonization method for the preparation of porous carbons with the environmentally friendly agents HCOOK and (HCOO)₂Ca for the first time. The bamboo waste-derived hydrochar was transformed into oxygen-doped porous carbons, which displayed a large surface area and pore volume, abundant oxygen content, graphene structure and many surface functional groups. These properties contributed to the extremely high sorption of large quantities of diethyl phthalate, which reached 761 mg g^-1. Surface adsorption, including pore filling, hydrogen bonding, and π-π stacking, rather than partitioning, was the main sorption process. Therefore, this study provides a sustainable and promising route for the preparation of porous carbons that can be applied in the efficient removal of organic pollutants.

Bio-Inspired Imprinting Materials for Biomedical Applications

Inspired by the recognition mechanism of biological molecules, molecular imprinting techniques (MITs) are imparted with numerous merits like excellent stability, recognition specificity, adsorption properties, and easy synthesis processes, and thus broaden the avenues for convenient fabrication protocol of bio-inspired molecularly imprinted polymers (MIPs) with desirable functions to satisfy the extensive demands of biomedical applications. Herein, the recent research progress made with respect to bio-inspired imprinting materials is discussed in this review. First, the underlying mechanism and basic components of a typical molecular imprinting procedure are briefly explored. Then, emphasis is put on the introduction of diverse MITs and novel bio-inspired imprinting materials. Following these two sections, practical applications of MIPs in the field of biomedical science are focused on. Last but not least, perspectives on the remaining challenges and future development of bio-inspired imprinting materials are presented.

Recent advances in magnetic composites as adsorbents for wastewater remediation

The scarcity of clean drinking water combined with other environmental and anthropogenic effects necessitates the demand for development of advanced technology for cleaning polluted water. Adsorption is one such technique that does not produce toxic byproducts and solves the problem of cleaning contaminated water at a lower cost. In recent years, magnetic composites, as adsorbent, have gained lot of attention due to their reusability which makes them sustainable and economical. This review article describes the challenges related to water quality, scarcity and then summarizes the current treatment technologies and advancement in the field of adsorption to resolve the prevailing concerns. The review includes an insight into the recent research being carried out in the field of magnetic composites and nanocomposites, as adsorbent, covering, probably, all aspects of what is going around the globe. Different materials, like polymers, biomaterials, clays and metal organic framework (MOF)-based magnetic composites and their applications in wastewater treatment processes have been included. The article is a comprehensive review on the application of different materials to detoxify various diverse pollutants with prime focus on magnetic composites. The thorough study of this review will surely bring upcoming researchers closer to the future possibilities of research in wastewater treatment.

Remediation of pharmaceuticals from contaminated water by molecularly imprinted polymers: a review

The release of pharmaceuticals into the environment induces adverse effects on the metabolism of humans and other living species, calling for advanced remediation methods. Conventional removal methods are often non-selective and cause secondary contamination. These issues may be partly solved by the use of recently-developped adsorbents such as molecularly imprinted polymers. Here we review the synthesis and application of molecularly imprinted polymers for removing pharmaceuticals in water. Molecularly imprinted polymers are synthesized via several multiple-step polymerization methods. Molecularly imprinted polymers are potent adsorbents at the laboratory scale, yet their efficiency is limited by template leakage and polymer quality. Adsorption performance of multi-templated molecularly imprinted polymers depends on the design of wastewater treatment plants, pharmaceutical consumption patterns and the population serviced by these wastewater treatment plants.

A new core–shell magnetic mesoporous surface molecularly imprinted composite and its application as an MSPE sorbent for determination of phthalate esters

In this study, a new core–shell magnetic mesoporous surface molecularly imprinted polymer (Fe₃O₄@SiO₂@mSiO₂-MIPs) which has specific adsorption and rapid adsorption rate for phthalate esters (PAEs) was prepared by a convenient method. Based on this composite as a magnetic solid phase extraction (MSPE) material, a rapid, efficient and sensitive matrix dispersion magnetic solid-phase extraction gas chromatography-mass spectrometry method (DMSPE-GC/MS) was developed for the determination of PAEs in multiple liquid samples. It is the first time that Fe₃O₄@SiO₂@mSiO₂-MIPs have been prepared by bonding amino groups on the surface of a double layer silicon substrate with diisononyl phthalate (DINP) as virtual template and 3-(2-aminoethyl)-aminopropyl trimethoxymethylsilane (TSD) as functional monomer. FT-IR, TEM, EDS, SEM, XRD, BET and VSM were used to characterize the composite. The adsorption isotherm and kinetics of Fe₃O₄@SiO₂@mSiO₂-MIPs showed that it possessed fast adsorption rates (approximately 5 min to reach equilibrium), high adsorption capacities (523.9 mg g⁻¹) and good recognition of PAEs. The real samples were preconcentrated by Fe₃O₄@SiO₂@mSiO₂-MIPs, under the optimum DMSPE-GC/MS conditions. Validation experiments showed that the method presented good linearity (R² > 0.9971), satisfactory precision (RSD < 5.7%) and high recovery (92.1–105.8%), and the limits of detection ranged from 1.17 ng L⁻¹ to 3.03 ng L⁻¹. The results indicated that the novel method had good sensitivity, high efficiency and wide sample application and was suitable for the determination of PAEs in liquid drink samples such as water, alcohol, beverages and so on.

A new core–shell magnetic mesoporous surface molecularly imprinted polymer (Fe3O4@SiO2@mSiO2-MIPs) which has specific adsorption for phthalate esters was synthesized by a facile and convenient method.

Application of Molecularly Imprinted Polymers in the Analysis of Waters and Wastewaters

The increase of the global population and shortage of renewable water resources urges the development of possible remedies to improve the quality and reusability of waste and contaminated water supplies. Different water pollutants, such as heavy metals, dyes, pesticides, endocrine disrupting compounds (EDCs), and pharmaceuticals, are produced through continuous technical and industrial developments that are emerging with the increasing population. Molecularly imprinted polymers (MIPs) represent a class of synthetic receptors that can be produced from different types of polymerization reactions between a target template and functional monomer(s), having functional groups specifically interacting with the template; such interactions can be tailored according to the purpose of designing the polymer and based on the nature of the target compounds. The removal of the template using suitable knocking out agents renders a recognition cavity that can specifically rebind to the target template which is the main mechanism of the applicability of MIPs in electrochemical sensors and as solid phase extraction sorbents. MIPs have unique properties in terms of stability, selectivity, and resistance to acids and bases besides being of low cost and simple to prepare; thus, they are excellent materials to be used for water analysis. The current review represents the different applications of MIPs in the past five years for the detection of different classes of water and wastewater contaminants and possible approaches for future applications.

[Recent advance of new sample preparation materials in the analysis and detection of environmental pollutants]

To successfully analyze complex samples and detect trace targets, sample pretreatment is essential. Efficient sample pretreatment techniques can remove or reduce interference from the sample matrix. It can also enrich analytes, thereby improving analytical accuracy and sensitivity. In recent years, various sample preparation techniques, including SPE, magnetic dispersion SPE, pipette tip SPE, stir bar extraction, fiber SPME, and in-tube SPME, have received increasing attention in environmental analysis and monitoring. The extraction efficiency mainly depends on the type of adsorbent material. Therefore, the development of efficient adsorbents is a crucial step toward sample preparation. This review summarizes and discusses the research advances in extraction materials over recent years. These extraction materials contain inorganic adsorbents, organic adsorbents, and inorganic-organic hybrid materials such as graphene, graphene oxide, carbon nanotubes, inorganic aerogels, organic aerogels, triazinyl-functionalized materials, triazine-based polymers, molecularly imprinted polymers, covalent organic frameworks, metal-organic frameworks, and their derivatives. These materials have been applied to extract different types of pollutants, including metal ions, polycyclic aromatic hydrocarbons, plasticizers, alkanes, phenols, chlorophenols, chlorobenzenes, polybrominated diphenyl ethers, perfluorosulfonic acids, perfluorocarboxylic acids, estrogens, drug residues, and pesticide residues, from environmental samples (such as water and soil samples). These sample preparation materials possess high surface areas, numerous adsorption sites, and allow extraction via various mechanisms, such as π-π, electrostatic, hydrophobic, and hydrophilic interactions, as well as hydrogen and halogen bond formation. Various sample pretreatment techniques based on these extraction materials have been combined with various detection methods, including chromatography, mass spectrometry, atomic absorption spectroscopy, fluorescence spectroscopy, and ion mobility spectroscopy, and have been extensively used for the determination of environmental pollutants. The existing challenges associated with the development of sample preparation techniques are proposed, and prospects for such extraction materials in environmental analysis and monitoring are discussed. Major trends in the field, including the development of efficient extraction materials with high enrichment ability, good selectivity, excellent thermal stability, and chemical stability, are discussed. Green sample pretreatment materials, environmentally friendly synthesis methods, and green sample pretreatment methods are also explored. Rapid sample pretreatment methods that can be conducted within minutes or seconds are of significant interest. Further, online sample pretreatment and automatic analysis methods have attracted increasing attention. Besides, real-time analysis and in situ detection have been important development directions, and are expected to be widely applicable in environmental analysis, biological detection, and other fields. Modern synthesis technology should be introduced to synthesize specific extraction materials. Controllable preparation methods for extraction materials, such as the in situ growth or in situ preparation of extraction coatings, will acquire importance in coming years. It will also be important to adopt high-performance materials from other fields for sample pretreatment. Organic-inorganic hybrid extraction materials can combine the advantages both organic materials and inorganic materials, and mutually compensate for any disadvantages. Extraction materials doped with nanomaterials are also promising. Although existing sample pretreatment techniques are relatively efficient, it is still imperative to develop novel sample preparation methods.

Imprinting Technology for Effective Sorbent Fabrication: Current State-of-Art and Future Prospects

In the last 10 years, we have witnessed an extensive development of instrumental techniques in analytical methods for determination of various molecules and ions at very low concentrations. Nevertheless, the presence of interfering components of complex samples hampered the applicability of new analytical strategies. Thus, additional sample pre-treatment steps were proposed to overcome the problem. Solid sorbents were used for clean-up samples but insufficient selectivity of commercial materials limited their utility. Here, the application of molecularly imprinted polymers (MIPs) or ion-imprinted polymers (IIPs) in the separation processes have recently attracted attention due to their many advantages, such as high selectivity, robustness, and low costs of the fabrication process. Bulk or monoliths, microspheres and core-shell materials, magnetically susceptible and stir-bar imprinted materials are applicable to different modes of solid-phase extraction to determine target analytes and ions in a very complex environment such as blood, urine, soil, or food. The capability to perform a specific separation of enantiomers is a substantial advantage in clinical analysis. The ion-imprinted sorbents gained interest in trace analysis of pollutants in environmental samples. In this review, the current synthetic approaches for the preparation of MIPs and IIPs are comprehensively discussed together with a detailed characterization of respective materials. Furthermore, the use of sorbents in environmental, food, and biomedical analyses will be emphasized to point out current limits and highlight the future prospects for further development in the field.

Molecularly Imprinted Polymer-Based Sensors for Priority Pollutants

Globally, there is growing concern about the health risks of water and air pollution. The U.S. Environmental Protection Agency (EPA) has developed a list of priority pollutants containing 129 different chemical compounds. All of these chemicals are of significant interest due to their serious health and safety issues. Permanent exposure to some concentrations of these chemicals can cause severe and irrecoverable health effects, which can be easily prevented by their early identification. Molecularly imprinted polymers (MIPs) offer great potential for selective adsorption of chemicals from water and air samples. These selective artificial bio(mimetic) receptors are promising candidates for modification of sensors, especially disposable sensors, due to their low-cost, long-term stability, ease of engineering, simplicity of production and their applicability for a wide range of targets. Herein, innovative strategies used to develop MIP-based sensors for EPA priority pollutants will be reviewed.