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The synthesis procedure and the spectral luminescent properties of nanoparticles containing the ytterbium complex of protoporphyrin IX dimethyl ester in a Lexan-based polymer matrix, promising for application in neoplasm diagnostics, are described. Nanoparticles have an increased luminescence lifetime in the 700–1100 nm near infrared region and almost no porphyrin free base fluorescence in the red spectral region, which shows promise in using the nanoparticles for diagnostic purposes. For theranostic purposes, the synthesis of multifunctional nanoparticles with a core of iron oxides and a Lexan-polymer shell containing the ytterbium complex of hematoporphyrin IX tetramethyl ester was carried out. We assume iron oxide nanoparticles are responsible for the local hyperthermia procedure.

The synthesized nanoparticles based on magnetite have been investigated for magneto-luminescent theranostics of tumors. A magnetite core provides hyperthermia, IR-luminescent diagnostics due to the Yb(асас)-complex of hematoporphyrin IX tetramethyl ether is carried out. It is shown that the magnetite core inclusion doesn’t lead to a significant decrease in the luminescence intensity of the Yb-complex in the synthesized nanocomposites.

The results of the main photophysical properties study of nanosized ytterbium porphyrins complexes, which are promising for use in a new method of cancer theranostics, namely, the method of magneto-luminescent theranostics, are presented. The spectral properties of some synthesized ytterbium porphyrins complexes have been investigated.

The solubilization of hydrophobic porphyrin photosensitizers (PPSes) to obtain corresponding water-soluble forms is an important line of modern antimicrobial photodynamic therapy. It is shown that a triblock copolymer of ethylene and propylene oxides, Pluronic F-127, one of the most nontoxic and effective polymer surface active substances (SASes), can be used for the conversion of hydrophobic tetraphenylporphyrin (TPP) and monosubstituted and tetrasubstituted hydroxy, amino, and nitro TPPs into water-soluble forms. It is found that Pluronic has a substantially higher solubilizing affinity (defined as the minimum molar concentration of an SAS required for the complete migration of porphyrin with a specific molar concentration to the aqueous phase) toward monosubstituted TPPs than to corresponding tetrasubstituted porphyrins. It is shown that with Pluronic in the organic phase, the activity of tetraphenylporphyrin in a test reaction of the oxidation of anthracene is higher than that of its monosubstituted and tetrasubstituted derivatives. In an aqueous medium, the activity of solubilized mono derivatives of TPP is comparable to that of unsubstituted TPP and is higher than the activity of the corresponding tetra derivatives of TPP.

The features of the electronic structure of Yb4d, N1s, C1s, O1s, Br3d core levels and the valence band of ytterbium metalloporphyrins Yb(acac)TPPBr8, Yb(acac)TPP, TPPBr8, and TPP are studied by photoelectron spectroscopy. The position and structure of the Yb4f level for Yb(acac)TPPBr8 are determined by resonant photoemission at the BESSY-II synchrotron center. Simulations of the electronic structure of the valence band show good agreement between the calculated and experimental data. The change in the electronic structure of porphyrins during implantation of the central atom of ytterbium, namely, a more uniform redistribution of the electron density between nitrogen atoms of pyrrole and aza groups, is revealed. The photoelectron spectra of Yb4d states demonstrate the trivalent metal state (Yb3+) in rare-earth metalloporphyrins. The partial destruction of bromine ytterbium tetraphenylporphyrin compound as a result of thermal action is demonstrated.

The measured quantum yield of Yb-2,4-dimethoxyhematoporphyrin (Yb-DMHP) in DMSO was 0.8%. It was found that molecular oxygen did not quench luminescence of the metal ion in Yb-DMHP, which was a diagnostic advantage while using this complex in practice. The kinetic characteristics of IR luminescence of the Yb porphyrin complex in DMSO/H2O mixtures were measured. The average lifetime of Yb3+ (2F5/2) in DMSO was 9.7 μs, which was an order of magnitude greater than that of the auto-fluorescence of biological tissues. Water molecules quenched effectively IR luminescence of Yb-DMHP. The integrated luminescence intensity of Yb3+ (2F5/2) depended non-linearly on the fraction of H2O in the DMSO/H2O mixtures. This was indicative of a complex quenching mechanism of Yb luminescence by surrounding molecules.

The electronic and local atomic structure of lutetium metalloporphyrins Lu(acac)TPP and precursor tetraphenylporphyrin (TPP) have been studied by X-ray photoelectron spectroscopy (XPS) and absorption spectroscopy (XAFS). The XPS spectroscopy data show changes in the electronic structure of tetraphenylporphyrins under incorporation of the lutetium atom: a redistribution of the electron density between the nitrogen atoms of the pyrrole- and aza- group and appearance of one broadened peak of the N1s state. The integer trivalent state of the rare-earth metal (Lu3+) in metalloporphyrins has been confirmed by both XPS and XAFS methods.

The creation and application of new low-toxic photosensitizers for the luminescence diagnostics of cancer are considered. The new photosensitizers weakly generate singlet oxygen, exhibit developed luminescence, and retain the tumor-tropic properties of the therapeutic photosensitizers. Twenty one ytterbium complexes of porphyrin compounds that differ by the substituents at the periphery of the porphyrin ring are synthesized. The absorption and luminescence spectra and the luminescence decay curves of these substances are studied. The primary toxicological and pharmacokinetic investigations are performed for the most promising compounds in the organisms of experimental animals. The experimental data prove that the Yb-porphyrin complexes are promising as low-toxic markers for the luminescence diagnostics of malignant tumors in the IR spectral range (975–985 nm) that are free of the phototoxicity typical of the conventional porphyrins at a relatively high luminescence contrast and the selective accumulation in tissue.

This paper describes the synthesis method and the spectral-luminescent properties of nanoparticles containing the ytterbium complex of protoporphyrin IX dimethyl ether in Lexan-based polymer matrix which are promising for use in tumours diagnostics. For theranostics purposes, the synthesis of multifunctional nanoparticles containing iron oxide core and Lexan-polymer shell, including ytterbium porphyrin complexes (YPC), was carried out. The iron oxide nanoparticles are responsible for carrying out the local hyperthermia procedure when exposed to a high-frequency magnetic field.

Features of the electronic structure of the valence band and Pt4f, Pt4d, C1s, O1s, and N1s core levels of the tetraphenylporphyrin (TPP) and synthesized Pt-TPP(p-COOCH3)4, Pt-TPP(m-OCH3)4, and PtCl2-TPP(m-OCH3)4 platinum metalloporphyrins are investigated by photoelectron spectroscopy.

The syntheses of complexes of natural and synthetic porphyrins with Pt, Pd, Rh, and Ru are reported. Their electronic absorption spectra, phosphorescence spectra, and lifetimes at room temperature both in the presence and in the absence of oxygen were studied. Variations in the nature of the central metal atom and in the substituents in pyrrol and phenyl rings allow the obtaining of metalloporphyrins phosphorescing at room temperature with various phosphorescence excitation and emission spectra.

The Vilsmeier formylation of metallocomplexes of isomeric meta- and para-methoxy-substituted tetraphenylporphyrines has was been studied. Formyl derivatives of meta-isomers were shown to form cyclization products not only in solutions, but also in the the solid state. The ability to undergo such transformations follows decreases in the trend following order: Co > Cu > Ni > Pd > Pt.

The mechanism of electroluminescence in polymeric thin-layer devices based on aromatic polyimides and various molecular complexes of Pt porphyrins as heavy-atom-containing luminophores was studied. On the basis of spectral and electron-hole transport properties of aromatic polyimides and Pt porphyrins, as well as the current concepts adopted in polymer photonics, the processes of singlet-singlet and triplet-triplet energy transfer in the examined single-layer systems aromatic PI-Pt porphyrin with a high electrophosphorescence quantum yield exceeding 2% are discussed.

The formylation reaction of platinum complexes of β-unsubstituted porphyrins was studied. The interaction of deuteroporphyrin IX derivatives with the Vilsmeyer reagent led to the selective formylation of their macrocycles in the β position. The resulting formyl derivatives of the porphyrins are of interest for fluorescent immunoassay.

The sensitivity of metal tetraphenylporphyrin complexes MTPP (M = PtII, PtIVCl2, ReIVO; TPP is tetraphenylporphyrin) to gaseous ammonia was studied. The gas sensitivity of MTPP is due to the heterogeneous catalytic oxidation of ammonia with the dioxygen ligands in the composition of MTPP. The influence of water vapor on the electrophysical properties of the surface layer of the complexes during adsorption of water and its participation in reactions of the coordinated ammonia and dioxygen were found. Empirical equations relating the conductivity of the MTPP surface layer to the content of water vapor and the concentration of gaseous ammonia were found.

Methods of synthesis of coproporphyrin and uroporphyrin by using bacteria of the genus Arthrobacterare proposed. Metal complexes of coproporphyrin and uroporphyrin with Pt, Pd, and Zn were synthesized. Their structures were identified by spectrophotometry, IR spectrometry, 1H-NMR, mass spectrometry, and HPLC. Data showing the possibility of using coproporphyrin III–metal complexes as luminophores for fluorescence detection of tumors was gathered. The current and prospective uses of metal complexes of water-soluble natural porphyrins in advanced immunofluorescence assays are discussed.

ZusammenfassungZiel: Es wurde untersucht, ob eine Einführung radioaktiver Isotope von Yb und Y in ausgewählte Porphyrine möglich ist. Außerdem sollten erste Daten zur Bioverteilung von radioaktiven Yb-169-Porphyrin-Komplexen gewonnen werden. Methoden: Die Synthesen der Metall-Porphyrin-Komplexe erfolgten mit geträgerten Radiometallen. Erste Tierversuche wurden an Mammakarzinom-tragenden Mäusen durchgeführt. Die Organe wurden 5 und 24 h nach i.v.-lnjektion im Bohrlochdetektor gemessen. Ergebnisse: Es konnten vier Yb-169-Porphyrin-Komplexe und Y-90-Porphyrin-Komplexe in nicht trägerfreier Form synthetisiert werden. Dies wurde anhand der Absorptionsspektren sowie mittels DC und HPLC bewiesen. Je nach Komplex lagen die Tumor/Untergrund-Verhältnisse im Durchschnitt zwischen 2 und 20. Schlußfolgerung: Die synthetisierten radioaktiven Metall-Porphyrin-Komplexe zeigen eine deutliche Tumoraffinität, die bei weiterer Verbesserung der Synthese (Ziel: Trägerreduzierung, andere Radionuklide) eine Tumorszintigraphie und vielleicht -therapie ermöglichen könnte.

A number of boradiazaindacene dyes containing a carboxyl group separated from a fluorophore by two methylene units were synthesized. The compounds have narrow spectral bands with absorption maxima at 480–530 nm and fluorescence maxima at 500–550 nm. Succinimide esters of these compounds and the corresponding fluorescent-labeled oligonucleotides were also prepared. Boradiazaindacene dyes can be used as fluorescent labels for oligonucleotides for analysis of melting curves of duplexes on microchips either by themselves or in combination with Texas Red. They can also be applied for labeling primers for polymerase chain reaction.

Synthesis of tetraphenyl substituted porphyrins with tert-butyl and methoxycarbonyl groups in meso-aryl radicals is described. It is shown that, during the condensation of dipyrromethanes with substituted benzaldehydes, a rearrangement occurs with the formation of a mixture of isomeric porphyrins. The character of these rearrangements depends on the position of substituents in the starting compounds.

It should be shown, that it is possible to insert radioactive isotopes of Yb and Y into some selected porphyrins. Besides, first informations about the biodistribution of Yb-169-por-phyrin-complexes should be obtained.Carrier added radioactive isotopes were used for the synthesis of the metal porphyrin complexes. The animal experiments were done with mamma carcinoma bearing mice. The activity of the organs was determined 5 and 24 h after i.v. injection in a well counter.Four Yb-169-porphyrin complexes and Y-90-porphyrin complexes could be synthesized in non-carrier-free form. This was verified by absorption spectra, TLC and HPLC. Depending on the complex, the average tumour/background ratios were between 2 and 20.The synthesized radioactive metal-porphyrin complexes showed a clear tumour-affinity which could be used for tumour scintigraphy or perhaps therapy if the synthesis is improved (goal: reduction of carrier, other radionuclides).

A fibre-optic oxygen sensor is described which is based on an oxygen-sensitive luminescent film made from platinum octaethylporphyrin and polystyrene. The luminescence and quenching characteristics of such films were studied for their use in a fibre-optic oxygen biosensor. A prototype oxygen sensor was made from this material, and was tested in aqueous solutions and in the gaseous phase at physiological oxygen concentrations. Measurements of luminescence intensity and decay time were employed to determine oxygen concentration from luminescence quenching. The main working characteristics of this prototype oxygen sensor were studied.

A flow-injection method for the determination of glucose in serum is presented. It is based on the enzymatic measurement of oxygen consumption detected via oxygen quenching of the luminescence of certain metalloporphyrins. Phosphorescent water-soluble Pt2+ and Pd(2+)-porphyrins have been characterized by luminescence spectroscopy and decay-time measurements in various buffers, and found to be suitable for oxygen detection in biological systems. A new method for the flow-injection analysis of glucose has been developed based on the use of a column of immobilized glucose oxidase and the indicators Pt(2+)-coproporphyrin III and Pd(2+)-coproporphyrin I. The system has been optimized for glucose determination in aqueous samples and in whole serum with the 0.5-200 mM glucose range. Twenty assays can be performed in an hour, and the system has potential for commercial development with biotechnological and medical applications.

To eliminate the masking effect of the background luminescence of endogenic substances in biological tissues and to increase the luminescence contrast values of malignant tumours, sarcoma-implanted mice were administered with ytterbium porphyrins instead of free porphyrin radicals. This was followed by in vivo luminescence localization of tumours using fibre-laser spectrofluorometry. The luminescence contrast values obtained reached 10—45 which is evidently not a limit.

The rare earth porphyrins represent a promising class of materials, due to their physical-chemical properties. A detailed study of the local structure of the RE series of porphyrins RETPP (RE = Yb, Er) was carried out by X-ray absorption spectroscopy (XAFS) using the synchrotron radiation. XAFS experiments prove the trivalent state of rare earth metals (Er, Yb) in metalloporphyrins. The relationship between the extended fine structure and the atomic structure of the porphyrin macrocycle with a central rare earth element (Yb, Er) is presented and discussed.