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The photosensitizing ability of an agent based on chlorin e6 (Photoditazin), which is used for photodynamic diagnosis and therapy, is compared with that of a new preparation on the basis of coproporphyrin III in the environment of a phosphate buffer and a simulated biological environment (albumin solution). The efficiency of singlet-oxygen production was estimated by EPR spectroscopy and spectroscopy in the UV and visible ranges with the use of “chemical traps” of singlet oxygen. By irradiating drugs with LED emission centered at λmax = 520 nm, we determined the quantum yield of singlet-oxygen production in a buffer solution; the obtained values are 0.60 and 0.37 for chlorine and coproporphyrin, respectively. The steady-state concentration of singlet oxygen upon irradiation of solutions of the studied photosensitizers with concentrations of 12–43 μМ and the density of radiation power within the 6–96 W/cm2 region was found to be in the region of 1010–1011 molecules/cm3. It is shown that the introduction into the solution of egg albumin (0.1%) reduces the sensitizing properties of the two drugs by two to three times, while the efficiencies of the preparations with respect to singlet-oxygen production become almost identical (0.19 and 0.17).

This paper presents a review of papers associated with the study of in vitro spectral, fluorescence, and photosensitizing properties, as well as the photostability of low-toxicity photosensitizers based on endogenous porphyrins—the disodium salt of 2,4-di(1-methoxyethyl) deuteroporphyrin IX (dimegin) and the tetrapotassium salt of coproporphyrin III—in comparison with chlorin preparations for medical purposes—Photoditazin, Radachlorin, and Fotolon—when photosensitizer solutions are irradiated in the visible range. The influence of transport additives and proteins on the properties mentioned above is discussed and studied. The results of the study are evidence that it is promising to use drugs based on endogenous porphyrins as effective agents for photodynamic therapy and fluorescence diagnosis, where, along with the photophysical properties of the photosensitizer, a key role is played by photostability, low toxicity, and accumulation selectivity in the pathological foci of the organism, and this is directly associated with the chemical structure of the drug. The results of the latest work carried out at S. I. Vavilov State Optical Institute on this specialization are treated separately.

The energy levels of the valence electrons of free ions with completely filled electron shells are analyzed. A linear correlation between term energies E nl and quantum defects dn nl is assumed to exist at constant values of orbital quantum numbers and ion charges for the Li, Na, Cu, Ag, and Au rows. The empirical dependence of quantum defects dn nl on the principle quantum number n is found. It can be used to estimate unknown term energies. It is also demonstrated that the linear dependences of the smooth nonlocal model pseudopotential parameter A nl of free ions on the term energy E nl is the result of their linear dependences on quantum defects dn nl .

An expression for the characteristic function of a nonlocal smooth model potential of an elementary metal is obtained in terms of the full nonlocal theory. The magnesium phonon spectra calculated using the expressions for a characteristic function agree satisfactorily with the experimental data.

An expression for the Fourier transform of the screening electron density of simple metals has been derived using smooth nonlocal model potentials of simple metals. The expression describes the contribution of conduction electrons to the atomic factors of X-ray scattering in simple metals. Aluminum was used as an example for numerical checking. Comparison with the results of similar calculations for the form factor of the Krasko-Gurskii model potential shows the importance of taking the nonlocality of the model potential into account.

In terms of the full nonlocal theory, an expression for the form factor of a smooth nonlocal model potential in an elementary metal is computed.

Conditions for preparing stable aqueous micellar solution of nonmodified fullerene C60 were optimized. The size distribution of the micellar particles was determined by transmission electron microscopy, and the negative charge of the micelles was proved. The mean particle diameter appeared to be ∼2.5 times smaller than that determined by dynamic light scattering. The possibility of generation of singlet oxygen in the modified system C60/H2O was demonstrated. The 1O2 luminescence signal at λ = 1268 nm lasts for ∼3 μs.

Experimental results and a kinetic model of generation of singlet oxygen during the interaction of oxygen molecules with optically pumped (lamp or laser radiation) fullerenes or fullerene-like nanoclusters in solutions, suspensions, and the form of various solid-phase membranes (surfaces) are presented. The experimental data on the photoluminescence of singlet oxygen in solutions of fullerenes are compared with the results of numerical simulation on the basis of the kinetic model with specified constants of photochemical processes. On the basis of the experimental results, it is shown that evaporation of a solution caused by pumping radiation yields long-lived gas-phase singlet oxygen. Release of gas-phase singlet oxygen from solid-phase fullerene-containing membranes (surfaces) is also demonstrated; however, this process is hindered by adsorption of singlet oxygen on the membrane surface. The prospects for creation of a singlet-oxygen generator on the basis of photoexcited fullerene molecules and fullerene-like nanoclusters are discussed.

The feasibility of the optically pumped (in particular, solar-pumped) fullerene-oxygen-iodine laser (FOIL) is considered. The singlet oxygen is assumed to be formed through the interaction of molecular oxygen with a mixture of (both lower and higher) fullerenes in a photogenerated triplet metastable state. The estimates based on a photokinetic model show that the solar-pumped FOIL efficiency can reach several tens of percent. The singlet-oxygen yield resulting from the interaction of optical pumping radiation with fullerenes in solutions is studied both theoretically and experimentally. As the optical pumping, we used laser radiation at 532 nm and broad-band emission of a lamp with a solarlike spectrum.

Using x-ray analysis, at % the existence of regions with a long-range order of the Cu3Au type has been established in a polycrystalline Pd-30 at % Au solid solution.

The first x-ray diffraction procedure suitable for the investigation of short-range order in polycrystalline alloys having a hexagonal close-packed (hcp) lattice is developed on the basis of the theory proposed by M. A. Krivoglaz for diffuse x-ray scattering by hcp single-crystal alloys. This procedure takes into account specific details of the crystal structure of the hcp lattice, in particular, the presence of two atoms in the unit cell and the close radii of the individual coordination spheres. The realistic character of the procedure is demonstrated experimentally in the example of hcp Mg-Dy and Mg-Tb alloys. The new procedure is used to calculate, for the first time, the modulating functions of linear and quadratic size effects in Mg-Dy and Mg-Tb alloys. It is shown that the size-effect modulating functions for coordination spheres with close radii have different characters, and their inclusion in diffuse scattering sets the stage for solving the problem of calculating the short-range order parameters on these spheres.

The possibility of lasing in the fullerene-oxygen-iodine system with optical excitation of fullerene is studied. Laser radiation with an energy of 25 mJ and a pulse duration of 5–10 ms is obtained.

We resume a complex study of a new Coproporphyrin III preparation obtained in vitro via microbiological synthesis in environment of a cultural medium of Arthrobacter globiformis with gaining of the coproporphyrin III tetrapotash salt sterilized aqueous solution with 94.5% purity. The main impurities have porphyrinic nature. The absorption spectrum shows that the preparation has multiple excitation bands in visible region with most pronounced maxima at 501 nm, 535 nm, and 556 nm, and a weak one at 606 nm. The most effective spectral range of its electronic states excitation can serve the region of a Soret band with maximum at 404 nm. Comparative luminescent and photosensitizing properties of Coproporphyrin III and Fotoditazin preparations have been studied. Luminescence and singlet oxygen quantum yields have been determined to be 0.03 and 0.37 (Coproporphyrin III) and 0.05 and 0.6 (Fotoditazin) correspondingly. A reduction of the quantum yields values at an introduction of a biological additive into aqueous solutions of the given preparations has been found. Preclinical trials of the preparation are performed. It is shown that Coproporphyrin III toxicity value is LD50 = 2400 ± 120 mg/kg, that allows to rank this preparation to the (V) class of almost nontoxical medicinal agents. It is shown that the preparation Coproporphyrin III has no teratogenic and allergenic properties and does not damage erythrocytes and thrombocytes. Absence of an influence of the preparation on the blood flow speed has been established. The results obtained thereby testify the absence of contra-indications for clinical tests of the Coproporphyrin III preparation on indicators of sharp toxicity.

Summary form only given. The possibility of development of fullerene-oxygen-iodine laser (FOIL) with optical pumping is theoretically and experimentally examined. It is shown, that FOIL can have coefficient of efficiency 30-50 % with optical pumping (including the sun-light one ). Singlet oxygen is generated because of interaction between photo-excited fullerenes molecules and flux of oxygen molecules. The experiments devoted to singlet oxygen formation in solutions of fullerenes and fulleroid materials with laser and lamp pumping were performed. Experimental results confirm the photochemical kinetic constants. Different solid-phase fullerene-containing membranes, ensuring the interaction of photo-excited fullerenes molecules and flux of oxygen molecules are described. We experimentally showed, that singlet oxygen leaves liquid or solid fullerene-containing media and reaches laser operating zone. The possibility of design of closed circuit operation of singlet oxygen generator, based on liquid fullerenes (fulleroid ) - containing media is experimentally demonstrated.

We present the experimental results on singlet oxygen generation via interaction of pumping photons (laser or lamp light), fullerenes (or fullerene-like nanoparticles - astralens) and oxygen in solid-state structures, in solutions and in suspensions. It was shown that the singlet oxygen is adsorbed by the solid-state fullerene coating and by powder-like astralen. It was shown that in course of evaporation of the solution (due to the pump action) is observed the singlet oxygen extraction to the gaseous phase, and the lifetime of 1ΔO2 grows significantly.© (2003) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Optical limiting mechanism in fullerene containing liquids and solid-state matrices, and suspensions of nanotubes and nanoclusters were investigated in wavelength range 0.3-1.315 mkm. Solutions of fullerenes C/sub 60/ and C/sub 70/ in toluene and CCL/sub 4/ were studied. The optical limiting in fullerene-containing media was determined by two processes- the reverse saturated absorption (RSA) and optically induced stimulated scattering (SS). This study has developed several variants multi-stage schemes of optical limiters on the base of fullerene-containing systems C/sub 60/-CCl/sub 4/, C/sub 60/-toluene and also at the suspensions of Astralene.

The contribution of light induced scattering to nonlinear optical limiting is theoretically and experimentally investigated. It is shown that light induced scattering is caused by fine-scale (1 divided by 10 micrometer) inhomogeneities formation, very low (comparable to spontaneous noise) laser beam inhomogeneities can evolve into light induced scattering. The numerical modeling of scattered radiation angular distribution and laser radiation attenuation in optical limiters was performed. The modeling results were compared with the experimental ones.

We consider the possibility to design the fullerene-oxygen- iodine laser with optical pumping (solar, particularly). It is assumed that singlet oxygen is formed at pass of molecular oxygen through (and interaction with) mixture of lower and higher fullerenes in the triplet metastable state obtained at illumination of fullerenes. The presented results of estimates by a photokinetic model show the opportunity to reach the efficiency of the FOIL with solar pumping at the level of several tens of percents. We present the results of experimental and theoretical studies of singlet oxygen yield at interaction of optical pumping with fullerene in solutions. Laser radiation with wavelength of 532 nm and wideband lamp radiation for imitation of solar radiation were used as pumping. The paper presents the first experimental results on the yield of singlet oxygen, produced in vacuum chamber via interaction of gas-phase molecular oxygen with fullerene devices, irradiated by solar-like lamp emission.

We present the results of theoretical and experimental studies on creation of nonlinear optical systems on a base of fullerene-containing media: power radiation limiters, photorefractive media for dynamic hologram recording, and devices for controlling spatial and temporal parameters of radiation.

This paper discusses the physical principles involved in creating a fullerene-oxygen-iodine laser (FOIL) with optical (including solar) pumping. The kinetic layout is discussed, and it is shown that the limiting efficiency of a FOIL can exceed 40% relative to the energy absorbed by the fullerenes. Experimental results of the lasing of singlet oxygen in liquid media (solutions and suspensions) and in solid-state structures containing both fullerenes and fullerenelike nanoparticles (FLNs) are presented. It is experimentally shown to be possible to release oxygen in the vapor phase by organizing the boiling of a solution (suspension), as well as by a gasdynamic desorption wave from solid-state FLN- or fullerene-containing structures. Preliminary experimental results are presented of the pulsed lasing of a FOIL with optical pumping, using the initial photodissociation of iodide to provide atomic iodine in the lasing zone. The principle of spectral separation of optical pumping is implemented in experiments on the lasing of a FOIL.

A theoretical and experimental study of the contribution of light-induced scattering to nonlinear optical limitation is made. It is shown that light-induced scattering makes a considerable contribution to the optical limitation of radiation by fullerene-containing solutions. Radiation is scattered by small-scale (1–10 μm) inhomogeneities of density, and the corresponding increments are rather large. Because of this, scattering can be initiated by small-scale inhomogeneities of the input beam. Numerical simulation of nonlinear scattering is made, and the angular distribution and limitation of radiation in optical limiters are calculated. The calculation results are compared with the experiment.