A new method, molecule wire polymer, was developed for the determination of cyanide based on the competitive reaction. The fluorescence of the molecule wire polymer is quenched due to ion-association with Pd 2+ and restored when cyanide was added into the system. The linear detection range is 5×10 -6—2×10 -4 mol/L and the detection limit is 1×10 -7 mol/L for cyanide under optimal conditions. The possible mechanism of the method was investigated by using absorption spectra. This approach provides a potential useful method for anion detection with a high sensitivity and selectivity.
The present paper covers a novel technology for the concentration of trace amounts of target oligonucleotide from the solution. This technique is based on a super-paramagnetic DNA nano-enricher constructed with a single strand DNA probe immobilized onto the surface of the super-paramagnetic nanoparticles prepared by using the water-in-oil microemulsion technique, employing silica as the shell and iron oxide as the core of the super-paramagnetic nanoparticles. The silica coated magnetic nanoparticles are (40±4) nm in size. And the magnetic nanoparticle is super-paramagnetic. Biotin labeled ssDNA(Biotin-5-(A)10-GAT-TCA-CGA-GGC-CCT-AGT-CG-3) was immobilized on the surface of silica coated magnetic nanoparticles. The complementary ssDNA could be enriched effectively and the characteristics of the enriched ssDNA have not changed, which will provide a novel technique and measurement for gene transfection, mutation detection, gene diagnosis, gene therapy and so on.