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The aim of this work was to develop an efficient method for the selective extraction and analysis of fenoxycarb, a carbamate pesticide, in mussel samples using a molecularly imprinted solid‐phase extraction device. The optimization of molecularly imprinted polymer synthesis was performed using the experimental design under the response surface methodology approach. A fast rebinding study and Freundlich isotherm adsorption were carried out to calculate binding capacity B, site number n, and affinity constant Kf. The optimum molecularly imprinted polymer was successfully used as sorbent of a solid‐phase extraction cartridge for the determination of fenoxycarb in real mussel samples. The range of linearity was 0.3–30 mg/L with a correlation coefficient of 0.991. The limit of detection was 0.247 mg/kg. The recovery of fenoxycarb extracted from mussel samples of Mediterranean sea was 97% (n = 3) with relative standard deviation between 6 and 7% proving the reliability of the developed method. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Abstract: 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 4.20×103 M−1) and low-affinity (Ka 0.79×103 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 55μg 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 0.7μgmL−1 of limit of detection, a linear range of 2.5–55μgmL−1 with a relative standard deviation of 2%. [Copyright &y& Elsevier]