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The issue of water contaminants, which affects human and environmental health, is not trivial. It is thus paramount to find new cheap and user friendly ways to detect and remove them from the environment. Here, the synthesis of a green chitosan (CS) based molecularly imprinted membrane for the detection and quantification of 4-nitrophenol (4-NO2Ph) in aqueous media is proposed. The concentration of 4-NO2Ph in a water solution was measured by HPLC analysis. CS as a functional polymer, 4-NO2Ph as template, 4-[(4-hydroxy)phenylazo]benzenesulfonic acid as ligand, and glutaraldehyde as crosslinker in the presence of polyethylene glycol as porogen were used. The membrane was characterized by SEM and Fourier transform IR analyses, which confirmed the CS and polyethylene glycol backbone of the membrane. Kinetic studies of the detection system were performed by using pseudo-first-order and pseudo-second-order models. Then, the binding efficiency between 195.33 µmol L−1 and 9235.55 µmol L−1 of 4-NO2Ph was evaluated, finding a maximum adsorption of 723.25 µmol 4-NO2Ph per gram of membrane consistent with the Qmax calculated from the Langmuir isotherm. The selectivity of the membrane versus three phenolic competitor molecules, sharing very similar molecular structure to 4-NO2Ph, was demonstrated. Finally, the applicability of the membrane to real-world samples was evaluated, by using drinking water spiked with 7.19 µmol L−1 of 4-NO2Ph, obtaining a removal efficiency of 70.6%. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry

Cardanol (CA) is a natural and renewable organic raw material obtained as the major by-product from the distillation of cashew nut shell liquid (CNSL). Thanks to its amphiphilic properties under alkaline conditions, was developed an environmental-friendly technology to produce engineered “green nanocarriers”, without use of any organic solvents, in which CA acts as the solvent as well as being the main component of the nanodispersions.

Nanotechnology has been utilized recently in medicine for the development of Drug Delivery Systems able to alter the kinetic profile of drug release that is very important in the administration of therapies for long periods as chemotherapy treatments, preventing damages to the normal surrounding tissue. This work aims to test new types of engineered green nanocarriers produced by an environmentalfriendly procedure for epithelial tumors treatment. Epithelial cancer is the largest single cause of death in both men and women, claiming over 6 million lives each year worldwide. For this reason, recently nanotechnology is attracting great interest in the search for new cancer therapies.

Environmental problems associated with water pollution, are today a serious problem that has attracted great attention of the global community. In particular, the release of various harmful heavy metal ions owing to industrial and agricultural processes represent today the main cause of pollution [1]. Mercury is one of the most hazardous elements for human health for its relatively solubility in water and living tissues. Common methods used for mercury separation from water samples include, liquid-liquid extraction [2], solid-liquid extraction [3], flotation [4] and membrane filtration [5] Moreover, many synthetic polymers opportunely functionalized by impregnation [6], grafting of commercial sorbents [7] or of home-made polymers [8] were prepared. However, a good selectivity is difficult to achieve with the previously mentioned materials. For this reason, highly selective Hg(II) imprinted polymers were prepared using different synthesis approaches and a correlation between the adsorption behavior and morphological characteristics of all polymers was made. Finally, selectivity studies using a mixture of different metal ions, were carried out.

In this work, we developed a novel approach to purify [11C]Raclopride ([11C]RAC), an important positron emission tomography radiotracer, based on tailored shape-recognition polymers, with the aim to substitute single-pass HPLC purification with an in-flow trap & release process. Molecular imprinting technology (MIT) applied to solid phase extraction (MISPE) was investigated to develop a setting able to selectively extract [11C]RAC in a mixture containing a high amount of its precursor, (S)-O-Des-Methyl-Raclopride (DM-RAC). Two imprinted polymers selective for unlabeled RAC and DM-RAC were synthesized through a radical polymerization at 65 °C using methacrylic acid and trimethylolpropane trimethacrylate in the presence of template molecule (RAC or DM-RAC). The prepared polymer was characterized by scanning electron microscopy and Fourier transform infrared spectroscopy and tested in MISPE experiments. The polymers were used in testing conditions, revealing a high retention capacity of RAC-MISPE to retain RAC either in the presence of similar concentrations of RAC and DM-RAC precursor (96.9%, RSD 6.6%) and in the presence of a large excess of precursor (90%, RSD 4.6%) in the loading solution. Starting from these promising results, preliminary studies for selective purification of [11C]Raclopride using this RAC-MISPE were performed and, while generally confirming the selectivity capacity of the polymer, revealed challenging applicability to the current synthetic process, mainly due to high backpressures and long elution times.

Molecular Imprinting Polymer (MIP) technology is a technique to design artificial receptors with a predetermined selectivity and specificity for a given analyte, which can be used as ideal materials in various application fields. In the last decades, MIP technology has gained much attention from the scientific world as summarized in several reviews with this topic. Furthermore, green synthesis in chemistry is nowadays one of the essential aspects to be taken into consideration in the development of novel products. In accordance with this feature, the MIP community more recently devoted considerable research and development efforts on eco-friendly processes. Among other materials, biomass waste, which is a big environmental problem because most of it is discarded, can represent a potential sustainable alternative source in green synthesis, which can be addressed to the production of high-value carbon-based materials with different applications. This review aims to focus and explore in detail the recent progress in the use of biomass waste for imprinted polymers preparation. Specifically, different types of biomass waste in MIP preparation will be exploited: chitosan, cellulose, activated carbon, carbon dots, cyclodextrins, and waste extracts, describing the approaches used in the synthesis of MIPs combined with biomass waste derivatives.

This manuscript describes the preparation of green nanovesicles by using cardanol as renewable starting material with embedded minor amounts of phthalazines, a class of heterocyclic bioactive compounds. The nanovesicles were prepared by stirring induced self-assembly in aqueous medium without involvement of any organic solvent. Dynamic light scattering studies and transmission electron microscopy revealed the formation of nanostructure with an average diameter in the range of 227-375 nm and a well defined spherical morphology. Potential antioxidant activity of nanovesicles were evaluated for the first time by 2,2?-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) scavenging assay and bleomycin-dependent DNA damage. Moreover, their cytotoxic effects were also investigated by 3-[4,5-dimethylthiazole-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assay on different tumour cell lines. Unloaded nanovesicles showed moderate antioxidant and antitumoural activity that was further enhanced particularly by embedding the 2-[4-(4-Hydrazinophthalazin-1-yl)-phenyl]-isoindole-1,3-dione compound.

This paper deals with the synthesis and full characterization of novel n-pentadecylphenol derivatives obtained through reduction of un-saturated long chain of cardanol which can contain different interesting functional groups (-NO2, -NH2 -NO) together with a saturated long chain. Cardanol is an important natural starting material obtained as the major component by vacuum distillation of cashew nut shell liquid, a renewable organic waste of the industrial production of cashew. Among the compounds herein described, of particular importance are the nitroso cardanolbased derivatives, which, as ligands can potentially form complexes with different metals. The saturated long chain present in these complexes confers particular properties such as good solubility in organic solvent and good processability for thin film monolayer formation

Viene descritto un polimero a stampo molecolare specifico per L-chinurenina ottenuto per polimerizzazione radicalica di almeno un monomero funzionale in presenza di un agente reticolante e un iniziatore per addizione radicalica al doppio legame comprendente le seguenti fasi: a) miscelare almeno un monomero funzionale con Lchinurenina utilizzata come molecola stampo in un opportuno solvente; b) aggiungere alla miscela ottenuta nella fase a) del procedimento un agente reticolante e un iniziatore per addizione radicalica a doppio legame per effettuare la polimerizzazione radicalica; c) lavare il prodotto ottenuto nella fase b) del procedimento con opportuni solventi per 10 rimuovere L-chinurenina dal polimero a stampo molecolare. E’ descritto, inoltre, un procedimento per l’estrazione di L-chinurenina da una soluzione e da un fluido biologico contente L-chinurenina, utilizzando la tecnologia MISPE in cui l’adsorbente è il detto polimero a stampo molecolare dell’invenzione.

A molecularly imprinted polymer (MIP) for the specific retention of neopterin has been developed. A set of 6 polymers was prepared by radical polymerization under different experimental condition using methacrylic acid as functional monomer and ethylene glycol dimethacrylate as crosslinker, with the aim to understand their influence on the efficiency of the MIP. The performance of each MIP was tested in batch experiments via their binding capacity. The MIP prepared in the presence of nickel ions in dimethylsulfoxide-acetonitrile mixture (P4) exhibited the highest binding capacity for neopterin (260 μmol per gram of polymer). A selectivity study with two other pteridines demonstrated the polymer P4 also to possess the best selectivity.

This study describes the preparation of ion-imprinted polymers (IIPs) for the selective removal of Hg(II) ions from aqueous media. Polymeric sorbents were prepared using different synthesis approaches to understand the influence of diphenylcarbazone (DPC), used as non-polymerizable ligand, on absorption performance. In particular, bulk polymerization was first used to prepare two polymers, IIP1 and IIP2, in the absence and presence of DPC. The trapping of the ligand in IIP2, demonstrated by Fourier Transform Infrared Spectroscopy, promotes the formation of ternary complexes with mercury ions, and 4-vinylpyridine induces an increase in binding performance, as indicated by the Kavalues (1.7 × 103±0.4 M−1 and 12.1 × 103±0.5 M−1, respectively) of IIP1 and IIP2 high affinity binding sites. A third polymer (IIP3) was also synthesized using precipitation polymerization to evaluate the contribution of morphological characteristics on absorption performance compared with the addition of DPC. Competitive studies revealed a stronger influence of IIP3 morphology on selectivity performance. Indeed, monodisperse microbeads were obtained only in this case. Finally, the applicability of the polymers to real-world samples was demonstrated through batch experiments using drinking water spiked with 1μgml−1 of Hg(II) ions, and the best removal efficiency of nearly 80% was obtained for IIP2.

An important challenge for scientific research is the production of artificial systems able to mimic the recognition mechanisms occurring at the molecular level in living systems. A valid contribution in this direction resulted from the development of molecular imprinting. In this work, a novel molecularly imprinted polymer composite membrane (MIM) was synthesized and employed for the selective detection in urine samples of 2-deoxyadenosine (2-dA), an important tumoral marker. By thermal polymerization, the 2-dA-MIM was cross-linked on the surface of a polyvinylidene-difluoride (PVDF) membrane. By characterization techniques, the linking of the imprinted polymer on the surface of the membrane was found. Batch-wise guest binding experiments confirmed the absorption capacity of the synthesized membrane towards the template molecule. Subsequently, a time-course of 2-dA retention on membrane was performed and the best minimum time (30 min) to bind the molecule was established. HPLC analysis was also performed to carry out a rapid detection of target molecule in urine sample with a recovery capacity of 85%. The experiments indicated that the MIM was highly selective and can be used for revealing the presence of 2-dA in urine samples.

Herein, we described the synthesis of a novel ion-imprinted membrane for the detection of palladium(II) prepared through the glutaraldehyde crosslinking of chitosan with a 4-[(4-Hydroxy)phenylazo]benzenesulfonic acid ligand trapped into the membrane. The imprinting technology was used to improve adsorption capacity and adsorption selectivity, and was combined with some advantages of the developed membrane, such as low cost and ease of preparation, water-friendly synthesis, and high biocompatible chitosan material. The membranes were characterized by Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), and Energy Dispersive X-ray Spectrometry (EDS). The results obtained showed a high swelling ratio with a maximum value of 16.4 (1640%) at pH 4 with a strong pH dependence. Batch rebinding experiments gave a maximum adsorption capacity of 101.6 mg of Pd(II) per gram of imprinted membrane. The Pd(II) adsorption behavior was well-described by a Langmuir model with a theoretical maximum adsorption capacity of 93.48 mg g−1, similar to the experimental one. Finally, a selectivity study versus Ag(I), Pb(II), and Fe(III) ions demonstrated a good selectivity of chitosan-imprinted membrane towards Pd(II).

Molecularly imprinting polymer technology is used to prepare a molecularly imprinted polymer (MIP) for the selective recognition of indole-3-carbinol (I3C), a chemopreventive and chemotherapeutic phytochemical associated with the anticancer activities of cruciferous vegetables. Prepolymerization study via nuclear magnetic resonance technique is done to choose the best functional monomer that establishes more interaction with the template. The prepared MIP is tested before in batch experiments and subsequently used as solid-phase extraction sorbent for the selective detection of I3C from standard solutions. In order to verify the selectivity of the MIP, the binding of structurally related compounds, such as indole-3-acetonitrile, teophylline, and tryptophan, on the polymer is investigated. The experiments indicate that the MIP is highly selective for I3C with an association constant of Ka = (1.37 ± 0.07) × 103 M−1. Standard mixture solution loaded on MIP-SPE cartridge give a recovery of 95% for I3C, while the other compounds are totally eluted during washing step. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40819.

A highly selective water compatible molecularly imprinted polymer (MIP) for 3-nitro-L-tyrosine (3NT), an oxidative stress marker associated with neurodegenerative disorders, was prepared and its use as solid-phase extraction (SPE) sorbent material was demonstrated. The MIP was prepared by bulk polymerization using methacrylic acid as functional monomer and acetonitrile as porogen with traces of acetic acid and trifluoroacetic acid. In order to evaluate its binding properties, the MIP was analyzed by batch rebinding experiments and subsequently used as SPE sorbent for the selective clean-up and pre-concentration of 3NT from standard solutions and spiked human urine samples. The results obtained from batch rebinding experiments showed the presence of two association constants corresponding to high-affinity (Ka 4.20X103 M-1) and low-affinity (Ka 0.79X103 M-1) binding sites. Standard mixture solution loaded on MIP-SPE cartridge gave a recovery of 95% for 3NT, while the other compounds were totally eluted during washing step. Percentage of recovery higher than 90%, with relative standard deviation of 2%, was also obtained when a maximum of 55 microg of 3NT is used in spiked urine sample and loaded into the cartridge. Validation of the analytical method for 3NT quantification in human urine gave 0.7 micromg mL-1 of limit of detection, a linear range of 2.5–55 microg mL-1 with a relative standard deviation of 2%.

Molecular Imprinting Technology (MIT) is a technique to design artificial receptors with a predetermined selectivity and specificity for a given analyte, which can be used as ideal materials in various application fields. Molecularly Imprinted Polymers (MIPs), the polymeric matrices obtained using the imprinting technology, are robust molecular recognition elements able to mimic natural recognition entities, such as antibodies and biological receptors, useful to separate and analyze complicated samples such as biological fluids and environmental samples. The scope of this review is to provide a general overview on MIPs field discussing first general aspects in MIP preparation and then dealing with various application aspects. This review aims to outline the molecularly imprinted process and present a summary of principal application fields of molecularly imprinted polymers, focusing on chemical sensing, separation science, drug delivery and catalysis. Some significant aspects about preparation and application of the molecular imprinting polymers with examples taken from the recent literature will be discussed. Theoretical and experimental parameters for MIPs design in terms of the interaction between template and polymer functionalities will be considered and synthesis methods for the improvement of MIP recognition properties will also be presented.

Fmoc-3-nitrotyrosine (Fmoc-3-NT) molecularly imprinted polymers (MIPs) were synthesized to understand the influence of several functional monomers on the efficiency of the molecular imprinting process. Acidic, neutral and basic functional monomers, such as acrylic acid (AA), methacrylic acid (MAA), methacrylamide (MAM), 2-vinylpyridine (2-VP), 4-vinylpyridine (4-VP), have been used to synthesize five different polymers. In this study, the MIPs were tested in batch experiments by UV-visible spectroscopy in order to evaluate their binding properties. The MIP prepared with 2-VP exhibited the highest binding affinity for Fmoc-3NT, for which Scatchard analysis the highest association constant (2.49 × 10(4) M(-1)) was obtained. Furthermore, titration experiments of Fmoc-3NT into acetonitrile solutions of 2-VP revealed a stronger bond to the template, such that a total interaction is observed. Non-imprinted polymers as control were prepared and showed no binding affinities for Fmoc-3NT. The results are indicative of the importance of ionic bonds formed between the -OH residues of the template molecule and the pyridinyl groups of the polymer matrix. In conclusion, 2-VP assists to create a cavity which allows better access to the analytes.