This work is devoted to investigation of new photosensitizer Bacteriochlorin p N-methoxycycloimide oxyme methyl ester
(BchlpOx-NOMe). Investigations of photosensitizer in vivo and experimental PDT were performed on animals bearing intramuscularly inoculated Erlich tumor and B16 melanoma. Characteristic absorption maximum of BchlpOx-NOMe around 795 nm is within the range of minimum intrinsic absorption of biological tissue. Dynamics and selectivity of sensitizer accumulation in tumor and normal tissue were estimated from spectra of absorption of sensitized tissue in vivo. The investigation has shown that the optimum time range to start PDT irradiation of tumor is 10-30 min after administration. Photosensitizer has shown high photodynamic efficiency of relatively large tumors, including high PDT efficiency in preliminary experiments with BDF1 mice bearing B16 melanoma, causing tumor growth inhibition more than 90% and prolongation of lifespan of tumor-bearing animals more than 60%.
The work was performed to estimate the influence of liposomal size distribution on the level and selectivity of accumulation of photosensitizer of near-IR spectral range Tiosens (liposomal form of aluminium hydroxide phenylthiophthalocyanine) in tumor. Tiosens liposome dispersions were prepared using classic Bangham procedure. Particle size was reduced and unified using Avanti Mini-Extruder equipped with Nucleopore membranes and high-pressure homogenizer Donor-1. Liposomal size distribution was determined by means of laser correlation spectroscopy. Dynamics and selectivity of Tiosens accumulation in Erlich tumor were measured in vivo using fluorescence spectroscopy. It was shown that level and selectivity of accumulation of liposome-encapsulated drug is determined mostly by content of small-sized fractions, while fractions of larger size are quickly cleared from blood by RES and not contribute in photosensitizer accumulation.
Current work is devoted to investigation of tetra-3-phenylthio-tetra-5-t-butylphthalocyanine [(PhS)4(t-Bu)4PcH2],
aluminium hydroxyde tetra-3-phenylthiophthalocyanine [(PhS)4PcAlOH] and zinc tetra-3-phenylthiophthalocyanine
[(PhS)4PcZn] as potential photosensitizers of near-infrared range. Investigations were performed on F1 mice bearing
Erlich tumor. Photosensitizers were administered intravenously in liposomal form at doses of 4-10 mg/kg. Dynamic and
selectivity of sensitizers' accumulation in tumor were estimated in vivo from fluorescence and absorption spectra of
sensitized tissue. Photosensitizers have shown high selectivity of accumulation in tumor comparing to normal tissue of
mice. Maxima of selectivity for (PhS)4(t-Bu)4PcH2, (PhS)4PcZn and (PhS)4PcAlOH achieve the values up to 2.5:1, 5:1
and 8:1 respectively. All photosensitizers completely clear from the normal tissue in 7-8 days. For PDT investigations
tumors were irradiated using 732 nm laser with power density of 100-500 mW/cm2 and light dose density up to
400 J/cm2. The photodynamic efficiency was estimated using the parameter of tumor growth inhibition (TGI). All
photosensitizers had shown high photodynamic efficiency of relatively large tumors. PDT using (PhS)4PcAlOH and
(PhS)4(t-Bu)4PcH2 caused pronounced TGI exceeding 80%. Using (PhS)4PcZn caused moderate TGI of 60%.
Investigations have shown that liposomal forms of phenylthiosubstituted phthalocyanine derivatives may be used to
develop new efficient photosensitizers for PDT.
This work is devoted to investigation of several new photosensitizers on a base of bacteriochlorin p macrocycle.
Investigations of photosensitizers in vivo and experimental PDT were performed on F1 mice bearing Erlich tumor and
BDF1 mice bearing B16 melanoma. Spectra of fluorescence and absorption of tissue were studied in vivo using fiberoptic
spectroanalyzer LESA. All investigated photosensitizers possess intensive absorption in a range of 730-800 nm,
where the intrinsic absorption of the biological tissue has its minimum. Dynamics and selectivity of sensitizer
accumulation in tumor and normal tissue were estimated from spectra of absorption or fluorescence of sensitized tissue
in vivo. The investigation has shown that the optimum time range to start PDT irradiation of tumor is 10-30 min after
administration. All photosensitizers clear from the normal tissue in less than 24 hours. Photodynamic efficiency was
estimated by comparison of the tumor volume growth in control and treated animal groups. All studied photosensitizers
have shown high photodynamic efficiency of relatively large tumors, index of tumor growth inhibition exceeded 70%.
Bacteriochlorin p N-methoxycycloimide oxyme methyl ester was also shown to be efficient for PDT of B16 melanoma,
causing tumor growth inhibition more than 90%.
Study is devoted to investigation of fluorescent and photodynamic properties of near-infrared photosensitizer bacteriochloriphyllide-serine. The peculiarities of its fluorescence excited by different lasers, dynamics and selectivity of accumulation were investigated. Photodynamic therapy of mice and investigation of tissue de-oxygenation during tumor irradiation were performed. It was shown that bacteriochloriphyllide-serine is an effective photosensitizer for PDT and fluorescent diagnostics of tumors.
This work is devoted to investigation of possibility to use the liposomal form of aluminium hydroxide tetra-3-phenylthiophthalocyanine as photosensitizer of near-infrared range. Aluminium hydroxide tetra-3-phenylthiophthalocyanine has shown high selectivity of accumulation in tumor comparing to normal tissue of mice as well as high photodynamic efficiency on mice bearing Erlich tumor (ELD) and lympholeucosis P-388. This compozition can be used to develop new effective photosensitizer for photodynamic therapy and fluorescent diagnostics.
The article is devoted to in vivo investigations of absorption in biological tissue sensitized by preparations used for diagnostics and therapy of tumors. Efficiency of method of difhse reflectance spectroscopy for in vivo evaluation of accumulation of sensitizers is demonstrated.
The study is devoted to investigation of fluorescent and photodynamic properties of near-infrared photosensitizer bacteriochlorophyllide-serine. The peculiarities of its fluorescence under different laser excitation conditions, dynamics of concentration and selectivity of accumulation were investigated. Photodynamic therapy of mice and investigation of tissue deoxygenation during tumor irradiation were performed. It was shown that bacteriochlorophyllide-serine is an effective photosensitizer for PDT and fluorescent diagnostics of tumors.
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