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Monitoring of over-expressed nucleolin in the cytoplasm facilitates early cancer diagnosis. Herein, we present a novel biosensing nanoscaffold based on anti-nucleolin aptamers and polymer-grafted graphene oxides for the fluorescent imaging of nucleolin in the cell cytoplasm, which can distinguish cancer cells from normal cells. [ABSTRACT FROM AUTHOR]

Exogenous and endogenous genotoxic carcinogens and their in vivo metabolites may result in DNA damage and cause adverse health effects. It is very difficult to specifically detect trace DNA damage in the presence of a large excess of unmodified nucleosides. Here we report a molecularly imprinted polymer (MIP) nanocomposite, namely nanoMIP, which can be used as a “plastic antibody” for specific recognition of benzo[a]pyrene diol epoxide (BPDE)–DNA adduct. Enhanced binding affinity (880 nM) of nanoMIPs was achieved by using two tailor-made functional monomers. The property of binding kinetics was greatly improved in virtue of the well-defined nanostructure, which was fabricated by initiators for continuous activator regeneration-atom transfer radical polymerization (ICAR-ATRP). The BPDE-adducted DNA can be specifically captured by synthetic nanoMIP. By taking advantage of this antibody-mimicking behavior, we further developed a fluorescently imaged particle counting immunoassay (FIPCIA) method for ultrasensitive detection of BPDE–ssDNA adducts using a laser scanning confocal microscope (LSCM). The number of countable fluorescent dots is proportional to the content of BPDE–ssDNA adducts in the DNA sample. The proposed plastic antibody-based FIPCIA method can detect traces of BPDE–DNA adducts as low as 18 pM in human lung carcinoma A549 cells. This highly-sensitive detection of DNA lesions offers a promising alternative to immunogenic antibody-based immunoassays for genomics and DNA modification analysis. [ABSTRACT FROM AUTHOR]

A new chiral stationary phase for nateglinide ( N-( trans-4-isopropylcyclohexylcarbonyl)-D-phenylalanine) based on a molecularly imprinted polymer has been prepared by non-covalent imprinting. For chromatographic analysis the effects on the separation of mobile phase composition, flow rate, and temperature were investigated, and the optimum conditions for HPLC were shown to be: mobile phase, acetonitrile; flow rate, 0.5 mL min−1; temperature, 25 °C. It was shown that the nateglinide-imprinted polymer was capable of recognizing the enantiomeric difference between nateglinide and its L enantiomer, whereas the non-imprinted polymer had no such ability. Scatchard analysis was used to investigate the binding characteristics of the nateglinide-imprinted stationary phase; this indicated that two classes of binding site were present in the imprinted polymer. The equilibrium dissociation constant ( K D) and the apparent maximum number ( Q max) of high- and low-affinity binding sites were 3.7 × 10−4 mol L−1 and 11.38 μmol g−1, and 1.81 × 10−3 mol L−1 and 27.73 μmol g−1, respectively. [ABSTRACT FROM AUTHOR]

Molecularly imprinted nanotubes for enantioselective drug delivery and controlled release are fabricated by the combination of template synthesis and ATRP grafting. The release of R-propranolol from the imprinted nanotubes in rats is restricted while the release of pharmacologically active S-enantiomer is greatly promoted. [ABSTRACT FROM AUTHOR]