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Novel water-soluble tetraarylporphyrin-labelled polymers have been synthesized by the reaction of bromoalkyl-containing poly(N-isopropylacrylamides) with 5-(4-pyridyl)-10,15,20-tri(4-methoxyphenyl) porphyrin. Corresponding Zn-porphyrin-containing polymers have also been prepared. Phase transition diagrams show that aqueous polymer solutions exhibit phase separation upon heating. Absorption spectra of the porphyrin-labelled polymers have been recorded in water and organic solvents. It is found that the absorption bands in aqueous polymer solutions are broadened and shifted bathochromically, the peak intensity of the Soret band in the polymer spectra being strongly lowered in water. Fluorescence properties of the polymers are briefly reported.

^99mTc(CO)₃-TPPS₄ was prepared via the precursor [^99mTc(CO)₃(H₂O)₃]⁺ and a preliminary investigation on its stability and behavior in Hep2 tumor cells and hepatoma-bearing mice were conducted. Labeling yield and stability of ^99mTc(CO)₃-TPPS₄ was radioactively analyzed by paper chromatography. Hep2 tumor cells were incubated with ^99mTc(CO)₃-TPPS₄ complex system in the substrate and isolated from the substrate for radioactivity count. Then ^99mTc(CO)₃-TPPS₄ complex system was intravenously injected in hepatoma-bearing mice and directly injected in tumor tissue of the mice. Mice were photographed using SPECT. Labeling yields of ^99mTc(CO)₃-TPPS₄ were more than 90% at pH = 7–8, 30 min, in a boiling bath, and it was stable for at least 14 h at pH = 2–8, rt ~95 °C. The uptake of ^99mTc(CO)₃-TPPS₄ in HepG2 tumor cells was only 3–4% with the maximum uptake-time of 20 min. The SPECT images of hepatoma-bearing nude mice showed no uptake or little retention of ^99mTc(CO)₃-TPPS₄ in the tumor tissue. Then the differences between ^99mTc(CO)₃-TPPS₄ and TPPS₄ were analyzed by fluoroscopy and molecular structure. It was found that the paper chromatography, HepG2 tumor cell uptake and the optimized porphyrin ring conformation of ^99mTc(CO)₃-TPPS₄ were quite different from those of TPPS₄. It was indicated that ^99mTc(CO)₃-TPPS₄ had no uptake or little retention in hepatic tumors, unlike those biological behaviors of TPPS₄. This may be due to the modification of porphyrin ring conformation of TPPS₄ by ^99mTc(CO)₃ core.

The synthesis of porphyrins conjugated with sugar moieties is described. meso-Aminophenyl-substituted and β-amino-substituted porphyrin derivatives reacted with benzyl protected glucuronic acid leading to gluco-conjugated hybrids, which after reductive deprotection of OH groups (H₂, 10% Pd/C) gave the desired target products of increased hydrophilicity. Alternatively, this type of similar conjugates were obtained through S_NAr reaction of meso-tetrakis(pentafluorophenyl)porphyrin with aminomethyl sacharides. The substitution took place selectively in para-position of meso-perfluorophenyl rings, thus giving rise to one, two, or three times substituted products carrying N-linked glucoside residues.

Porphyrins and phthalocyanines are currently a prevalent topic with great potential due to their abundant photonic/electronic properties. The study of porphyrin or phthalocyanine supramolecular architectures on solid surfaces is laying the foundation for the further development of molecular electronics or other structures in applications. Above all, the invention of scanning tunneling microscopy (STM) has opened a new path to explore these concepts on surfaces. Self-assemblies on solid surfaces can be probed with STM at submolecular resolutions to disclose the conformations and arrangements of molecules on an individual molecule basis. In this paper, the progress of STM research on porphyrin and phthalocyanine derivatives over past ten years is reviewed. We introduce the self-assembled structures of different porphyrins or phthalocyanines. Throughout the review, the structures, thermodynamics, and dynamics have been emphasized, which are essential current and future research themes.

Spore-producing bacteria have proved to be extremely resistant to solar and photocatalytic disinfection techniques. Porphyrin derivatives that produce active oxygen species in the presence of light and molecular oxygen can be an interesting approach for the inactivation of these highly resistant bacterial spores. This work reports on studies of photodynamic inactivation (PDI) of Bacillus cereus endospores, taken as model-endospores, using several porphyrin derivatives, differing in the number of positive charges. The results show definitively and contrary to what was previously reported in the literature, that porphyrin derivatives are effective photosensitizers for the inactivation of bacterial endospores making PDI a promising approach for the disinfection of living tissues, contaminated materials and wastewater.