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In this work, manganese porphyrins were immobilized on hybrid nanocomposite microspheres through amide bond using Fe 3 O 4 as hard templates. The catalyst was characterized by N 2 adsorption–desorption isotherm (BET specific surface area), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), and ultraviolet and visible spectroscopy (UV–vis) analysis. The results showed the average size of the hybrid nanocomposite microspheres is 450 nm in diameter and the supported metalloporphyrin catalysts remained reactive after removing Fe 3 O 4 leaving the silica support with micropores. The catalytic performance of the as-prepared catalysts without Fe 3 O 4 core instead of with the core was significantly enhanced as a result of the homogeneous catalysis in a heterogeneous catalyst, and the conversion of ethylbenzene was up to 22.9%. The catalyst also possessed high stability, and could be reused 6 times without remarkable loss of the catalytic activity, compared to the unsupported counterpart.

Starting from pyridine-2,6-dicarboxylic acid (DPA), a series of novel pyridine-2,6-dicarboxylic acid derivatives were synthesized. In these compounds, 4-(hydroxymethyl)pyridine-2,6-dicarboxylate (4-HMDPA) and 4-[(bis-carboxymethyl-amino)-methyl]-pyridine-2,6-dicarboxylic acid (4-BMDPA) were used as multifunctional ligands to coordinate with Tb(III) and Eu(III) and the complexes were prepared. The fluorescence properties of the solid complexes and their solutions were investigated in detail. The results indicated that the weak election-withdrawing group 4-hydroxymethyl in 4-position of pyridine in 4-HMDPA could weaken the fluorescence intensity of the lanthanide complexes. The contradistinctive experimental results showed that the fluorescence intensities of these complexes are related to pH values of the aqueous solutions and the dipole moments of solvent molecules: in the neutral aqueous solutions, the fluorescence intensities of these complexes were strongest, while the dipole moments were lower when the fluorescence intensities were stronger. 4-BMDPA is the better sensitizer and may be used as time-resolved fluoroimmunoassay.

Piperazinyl-porphyrin, 5,10,15,20-tetra[4-(N-ethylpiperazinyl)phenyl]porphyrin (TEPPH2), was synthesized based on the special affinity of porphyrin to cancer cells and the antitumor activity of piperazine compounds. Its structure was characterized by UV-vis and 1H NMR spectra and elemental analysis. A model for the interaction between TEPPH2 and calf thymus DNA was built, and the binding mechanism was investigated by UV-vis and fluorescence spectra. The results indicated that TEPPH2 could intercalate into the base pairs of DNA strongly. One calf thymus DNA molecule could bind 88 TEPPH2 molecules, and the binding constant K is 8.4×106 L·mol-1. The binding number and binding constant of TEPPH2 with DNA are higher than those of the known anti-tumor drugs, tetrakis(4-N-methylpyridyl)porphine and the Schiff bases Ca/sal-his and Ni/sal-aln.