Synthesis and application of a carbamazepine-imprinted polymer for solid-phase extraction from urine and wastewater

A molecularly imprinted polymer (MIP) designed to enable the selective extraction of carbamazepine (CBZ) from effluent wastewater and urine samples has been synthesised using a non-covalent molecular imprinting approach. The MIP was evaluated chromatographically in the first instance and its affinity for CBZ also confirmed by solid-phase extraction (SPE). The optimal conditions for SPE consisted of conditioning of the cartridge using acidified water purified from a Milli-Q system, loading of the sample under basic aqueous conditions, clean-up using acetonitrile and elution with methanol. The attractive molecular recognition properties of the MIP gave rise to good CBZ recoveries (80%) when 100 mL of effluent water spiked with 1 μg L⁻¹ was percolated through the polymer. For urine samples, 2 mL samples spiked with 2.5 μg L⁻¹ CBZ were extracted with a recovery of 65%. For urine, the linear range was 0.05-24 mg L⁻¹, the limit of detection was 25 μg L⁻¹ and precision, expressed as relative standard deviation at 0.5 mg L⁻¹ (n = 3), was 3.1% and 12.6% for repeatability and reproducibility between days, respectively.     

Micellization and gelation of aqueous solutions of star-shaped PEG-PCL block copolymers consisting of branched 4-arm poly(ethylene glycol) and polycaprolactone blocks

Star-shaped block copolymers consisting of non-toxic poly(ethylene glycol) and biodegradable polycaprolactone ((PEG5K-PCL)₄) were synthesized by ring-opening polymerization of the ε-caprolactone monomer with hydroxyl-terminated 4-armed PEG as initiator. These biodegradable, amphiphilic star block copolymers showed micellization and sol-gel transition behaviors in aqueous solution with varying concentration and temperature. In the dilute aqueous solutions of star block copolymers, micellization behavior occurred over specific concentration. The 1,6-diphenyl-1,3,5-hexatriene (DPH) solubilization method was used to determine the critical micellization concentration (CMC) of star block copolymers. The obtained micelle size increased with increasing hydrophobic PCL block length. In high-concentration solutions, the star block copolymers showed temperature-sensitive sol-gel transition behavior. The morphology of the micelle and gel was investigated by atomic force microscopy (AFM). As a result, the micelles showed a core-corona spherical structure at concentration near CMC, while the gel showed a mountain-chain-like morphology picture. It was proposed that with increasing the micelle concentration the worm-like micelle clusters formed firstly and the gel was constructed by the packing of micelle clusters.     

A novel gel polymer electrolyte based on poly ionic liquid 1-ethyl 3-(2-methacryloyloxy ethyl) imidazolium iodide

Poly ionic liquid 1-ethyl 3-(2-methacryloyloxy ethyl) imidazolium iodide (PEMEImI) as a single-ion conductor was designed and synthesized. When appropriate amount of suitable plasticizers, I₂ and polyacrylonitrile (PAN) were incorporated into it, the complex formed gel polymer electrolyte. Chemical structure, thermal behavior and ionic conductive properties of the gel polymer electrolyte were investigated by Raman spectra, UV-Vis spectra, differential scanning calorimetry (DSC), and complex impedance analysis, respectively. For the new gel polymer electrolyte, the ionic conductivity of about 1 × 10⁻³ S cm⁻¹ at room temperature was achieved.     

Polyaniline and polypyrrole: A comparative study of the preparation

Aniline and pyrrole have been oxidized with ammonium peroxydisulfate in aqueous solutions, in the presence of equimolar quantities of hydrochloric acid. The oxidation of pyrrole was faster; the induction period typical of aniline oxidation was absent in the case of pyrrole. As the proportion of oxidant-to-monomer molar concentration increased up to 1.5, the yield increased in both cases. Similarities between the two oxidations are illustrated and discussed. The oxidant-to-monomer molar ratio 1.25 is proposed to be the optimum stoichiometry, in the accordance with the data published in the literature. The conductivities of the polymers prepared were only slightly dependent on the oxidant-to-monomer ratio in the range 0.3-1.5, and were of the order of 10⁰ S cm⁻¹ for polyaniline and ∼10⁻²-10⁻¹ S cm⁻¹ for polypyrrole. Outside this interval, the conductivity of both polymers was reduced. Polyaniline having conductivity ∼10 S cm⁻¹ was produced in solutions of phosphoric acid of various concentrations. On the contrary, the conductivity of polypyrrole was reduced as the concentration of phosphoric acid became higher. The type of protonation is discussed with the help of FTIR spectra by analyzing the ammonium salts obtained after deprotonation. Sulfate or hydrogen sulfate anions produced from peroxydisulfate always constitute a part of the counter-ions.     

Click Functionalization of a Dibenzocyclooctyne‐Containing Conjugated Polyimine

A conjugated poly(phenyl‐co‐dibenzocyclooctyne) Schiff‐base polymer, prepared through polycondensation of dibenzocyclooctyne bisamine (DIBO‐(NH₂)₂) with bis(hexadecyloxy)phenyldialdehyde, is reported. The resulting polymer, which has a high molecular weight (M_n>30 kDa, M_w>60 kDa), undergoes efficient strain‐promoted alkyne–azide cycloaddition reactions with a series of azides. This enables quantitative modification of each repeat unit within the polymer backbone and the rapid synthesis of a conjugated polymer library with widely different substituents but a consistent degree of polymerization (DP). Kinetic studies show a second‐order reaction rate constant that is consistent with monomeric dibenzocyclooctynes. Grafting with azide‐terminated polystyrene and polyethylene glycol monomethyl ether chains of varying molecular weight resulted in the efficient syntheses of a series of graft copolymers with a conjugated backbone and maximal graft density.     

Single Lithium‐Ion Conducting Polymer Electrolytes Based on a Super‐Delocalized Polyanion

A novel single lithium‐ion (Li‐ion) conducting polymer electrolyte is presented that is composed of the lithium salt of a polyanion, poly[(4‐styrenesulfonyl)(trifluoromethyl(S‐trifluoromethylsulfonylimino)sulfonyl)imide] (PSsTFSI^?), and high‐molecular‐weight poly(ethylene oxide) (PEO). The neat LiPSsTFSI ionomer displays a low glass‐transition temperature (44.3 °C; that is, strongly plasticizing effect). The complex of LiPSsTFSI/PEO exhibits a high Li‐ion transference number (t_Li⁺=0.91) and is thermally stable up to 300 °C. Meanwhile, it exhibits a Li‐ion conductivity as high as 1.35×10^?4 S cm^?1 at 90 °C, which is comparable to that for the classic ambipolar LiTFSI/PEO SPEs at the same temperature. These outstanding properties of the LiPSsTFSI/PEO blended polymer electrolyte would make it promising as solid polymer electrolytes for Li batteries.     

Superspreading on Immersed Gel Surfaces for the Confined Synthesis of Thin Polymer Films

Liquid spreading is of significant interest in science and technology. Although surface topography engineering and liquid surface‐tension regulating can facilitate spreading, the spreading layers in these strategies are inevitably inhomogeneous or contaminated with surfactants. Herein, we show a general strategy to realize the superspreading of liquids on mutually soluble gel surfaces. The cooperation of the hydraulic pressure under liquid phase and liquid‐like property of gel surfaces can dramatically eliminate the local pinning effect and enhance the advancement of three‐phase contact line, thus forming stable and homogeneous superspreading liquid layers. Such liquid layers can be converted into various functional thin polymer films with controlled thicknesses (nm‐ to µm‐scale) through one‐step polymerization of the reactants. Our strategy offers opportunities for large‐scale synthesis of versatile functional thin films for various applications.     

Combining Biomimetic Block Copolymer Worms with an Ice‐Inhibiting Polymer for the Solvent‐Free Cryopreservation of Red Blood Cells

The first fully synthetic polymer‐based approach for red‐blood‐cell cryopreservation without the need for any (toxic) organic solvents is reported. Highly hydroxylated block copolymer worms are shown to be a suitable replacement for hydroxyethyl starch as a extracellular matrix for red blood cells. When used alone, the worms are not a particularly effective preservative. However, when combined with poly(vinyl alcohol), a known ice‐recrystallization inhibitor, a remarkable additive cryopreservative effect is observed that matches the performance of hydroxyethyl starch. Moreover, these block copolymer worms enable post‐thaw gelation by simply warming to 20 °C. This approach offers a new solution for both the storage and transport of red blood cells and also a convenient matrix for subsequent 3D cell cultures.     

Monodisperse Cylindrical Micelles of Controlled Length with a Liquid‐Crystalline Perfluorinated Core by 1D “Self‐Seeding”

Precise control over the morphology and dimensions of block copolymer (BCP) micelles has attracted interest due to the potential of this approach to generate functional nanostructures. Incorporation of liquid crystalline (LC) block can provide additional ways to vary micellar morphologies, but the formation of uniform micelles with controllable dimensions from LC BCPs has not yet been realized. Herein, we report the preparation of monodisperse cylindrical micelles with a LC poly(2‐(perfluorooctyl)ethyl methacrylate (PFMA) core via a fragmentation‐thermal annealing (F‐TA) process, resembling the “self‐seeding” process of crystalline BCP micelles. The average length of the cylinders increases with annealing temperature, with a narrow length distribution (L_w/L_n<1.1). We also demonstrate the potential application of the cylinders with LC cores as a cargo‐carrier by the successful incorporation of a hydrophobic fluorescent dye tagged with a fluorooctyl group.     

A novel molecularly imprinted method with computational simulation for the affinity isolation and knockout of baicalein from Scutellaria baicalensis

A novel molecularly imprinted polymer (MIP) was synthesized by precipitation polymerization with baicalein (BAI) as the template and used as solid‐phase extraction (SPE) adsorbent, aiming at the affinity isolation and selective knockout of BAI from Scutellaria baicalensis Georgi (SB). We used computational simulation to predict the optimal functional monomer, polymerization solvent and molar ratio of template to functional monomer. Characterization and performance tests revealed that MIP exhibited uniform spherical morphology, rapid binding kinetics, and higher adsorption capacity for BAI compared with nonimprinted polymer (NIP). The application of MIP in SPE coupled with high‐performance liquid chromatography to extract BAI from SB showed excellent recovery (94.3%) and purity (97.0%). Not only the single BAI compound, but also the BAI‐removed SB extract was obtained by one‐step process. This new method is useful for isolation and knockout of key bioactive compounds from herbal medicines. Copyright © 2015 John Wiley & Sons, Ltd.