1
|
Phillips D, Dhami S, Ostler R, Petrasek Z. The Dimerisation of Phthalocyanines. PROGRESS IN REACTION KINETICS AND MECHANISM 2019. [DOI: 10.3184/007967403322807390] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
In this review, we have shown that the dimerisation of phthalocyanine compounds, notably here the sulphonated aluminium phthalocyanines, is dependent upon concentration, on the medium in which the dye is dissolved, and upon pH. Complex equilibria between various monomer and dimer species are observed as a function of pH, and the probable structures of the dimers elucidated by semi-empirical and ab initio calculations. The formation of a red-shifted dimer leads to the quenching of monomer singlet state in concentrated solution, in reverse micelles, and in lipid vesicles, and this behaviour can account for the fluorescence intensity distributions and decay characteristics of phthalocyanine dyes in living cells as a function of irradiation time.
Collapse
Affiliation(s)
- David Phillips
- Department of Chemistry, Imperial College London, Exhibition Road, London SW7 1AZ, UK
| | - Suman Dhami
- Department of Chemistry, Imperial College London, Exhibition Road, London SW7 1AZ, UK
| | - Richard Ostler
- Department of Chemistry, Imperial College London, Exhibition Road, London SW7 1AZ, UK
| | - Zdenek Petrasek
- Department of Chemistry, Imperial College London, Exhibition Road, London SW7 1AZ, UK
| |
Collapse
|
2
|
Jiang Z, Shao J, Yang T, Wang J, Jia L. Pharmaceutical development, composition and quantitative analysis of phthalocyanine as the photosensitizer for cancer photodynamic therapy. J Pharm Biomed Anal 2014; 87:98-104. [DOI: 10.1016/j.jpba.2013.05.014] [Citation(s) in RCA: 86] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2013] [Revised: 05/04/2013] [Accepted: 05/11/2013] [Indexed: 12/22/2022]
|
3
|
Abstract
The application of phthalocyanine derivatives in medicine as photosensitizers for photodynamic therapy of cancer diseases is reviewed. The emphasis is on the work of Russian authors, which is less covered in the scientific literature.
Collapse
Affiliation(s)
- EUGENY A. LUKYANETS
- Organic Intermediates and Dyes Institute, 1/4 B. Sadovaya Street, 103787 Moscow, Russia
| |
Collapse
|
4
|
Khene S, Ogunsipe A, Antunes E, Nyokong T. Microwave synthesis and photophysics of new tetrasulfonated tin(II) macrocycles. J PORPHYR PHTHALOCYA 2012. [DOI: 10.1142/s108842460700014x] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
This work reports on the microwave synthesis of tetrasulfonated tin phthalocyanine and tetrasulfonated tin α,β,γ-tetrabenzcorrole. The latter was only formed at low ratios (<1:8) of 4-sulfophthalic acid to urea. Both complexes are aggregated in aqueous media, but can be partly or fully disaggregated by the addition of Triton X-100. The α,β,γ-tetrabenzcorrole complex has lower triplet life times and yields, while the binding constant and quenching (of bovine serum albumin) constant are lower for α,β,γ-tetrabenzcorrole compared to tetrasulfonated tin phthalocyanine.
Collapse
Affiliation(s)
- Samson Khene
- Department of Chemistry, Rhodes University, Grahamstown 6140, South Africa
| | - Abimbola Ogunsipe
- Department of Chemistry, Rhodes University, Grahamstown 6140, South Africa
- Department of Chemistry, University of Lagos, Lagos, Nigeria
| | - Edith Antunes
- Department of Chemistry, Rhodes University, Grahamstown 6140, South Africa
| | - Tebello Nyokong
- Department of Chemistry, Rhodes University, Grahamstown 6140, South Africa
| |
Collapse
|
5
|
Kuznetsova NA, Gretsova NS, Derkacheva VM, Kaliya OL, Lukyanets EA. Sulfonated phthalocyanines: aggregation and singlet oxygen quantum yield in aqueous solutions. J PORPHYR PHTHALOCYA 2012. [DOI: 10.1142/s1088424603000203] [Citation(s) in RCA: 117] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The influence of sulfonation degree (n) and central atom nature on singlet oxygen quantum yield (ΦΔ) were studied for a series of sulfonated phthalocyanine metal complexes MPcS n mix . It was found that in DMSO, where the studied dyes exist as monomers, ΦΔ values are independent of number and position of the sulfogroups and are equal to 0.11 ± 0.02, 0.19 ± 0.03, 0.37 ± 0.05, 0.38 ± 0.05 and 0.68 ± 0.10 for the metal-free and Mg , Gd , Al and Zn complexes, correspondingly. However, in aqueous solutions, aggregation of the dyes determines their photochemical activity. Substitution in adjacent to macrocycle 3 and 6 benzene positions interferes with aggregation compared to 4 and 5 positions, presumably due to enhanced steric hindrances in the former case. In the ZnPcS n mix series (n varied from 2 to 4), as an example, the linear relationship between degree of aggregation and ΦΔ indicates that only the monomer fraction of the dye is responsible for singlet oxygen production. For less sulfonated samples the order of activity of the dyes in water is as follows: H 2 PcS n mix < M II PcS n mix < M III PcS n mix which is in contrast to their tendencies to form aggregates.
Collapse
Affiliation(s)
- Nina A. Kuznetsova
- Organic Intermediates and Dyes Institute, B. Sadovaya ¼, Moscow 101999, Russia
| | | | | | - Oleg L. Kaliya
- Organic Intermediates and Dyes Institute, B. Sadovaya ¼, Moscow 101999, Russia
| | - Evgeny A. Lukyanets
- Organic Intermediates and Dyes Institute, B. Sadovaya ¼, Moscow 101999, Russia
| |
Collapse
|
6
|
Kimani SG, Phillips JB, Bruce JI, MacRobert AJ, Golding JP. Antioxidant Inhibitors Potentiate the Cytotoxicity of Photodynamic Therapy. Photochem Photobiol 2011; 88:175-87. [DOI: 10.1111/j.1751-1097.2011.01022.x] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
|
7
|
Woodhams J, Lou PJ, Selbo PK, Mosse A, Oukrif D, MacRobert A, Novelli M, Peng Q, Berg K, Bown SG. Intracellular re-localisation by photochemical internalisation enhances the cytotoxic effect of gelonin — Quantitative studies in normal rat liver. J Control Release 2010; 142:347-53. [DOI: 10.1016/j.jconrel.2009.11.017] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2009] [Accepted: 11/16/2009] [Indexed: 10/20/2022]
|
8
|
Bonneau S, Vever-Bizet C, Mojzisova H, Brault D. Tetrapyrrole-photosensitizers vectorization and plasma LDL: A physico-chemical approach. Int J Pharm 2007; 344:78-87. [PMID: 17656052 DOI: 10.1016/j.ijpharm.2007.06.019] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2007] [Revised: 06/01/2007] [Accepted: 06/06/2007] [Indexed: 11/16/2022]
Abstract
A photosensitizer is defined as a chemical entity able to induce, under light-irradiation effect, a chemical or physical alteration of another chemical entity. Thanks to their preferential retention in proliferating tissues, some photosensitizers are therapeutically used such as in photodynamic therapy (PDT). Besides, this method has already been approved for several indications. The selectivity of photosenzitizers for cells in proliferation involves both their association with low density lipoproteins (LDLs) and their ability to cross membranes under various pH conditions. The photosensitizers used are in most cases based on the porphyrin structure, but other compounds, of which far-red-light absorption properties are most compatible with biological tissues irradiation, have been developed, such as phthalocyanines. This paper presents physico-chemical studies of the interaction of a disulfonated aluminium phthalocyanine (AlPcS2) with human LDLs. The data obtained are compared with the parameters of the interaction of these lipoproteins with deuteroporphyrin (DP) and chlorin e6 (Ce6). A close attention is paid to the dynamic aspects of these phenomena. The data obtained on these simple systems then allowed us to interpret the sub-cellular localization of the photosensitizers on a human line of fibroblasts, and to evaluate the influence of LDLs on the intracellular distribution of the compounds. This last point is of major importance because the localization of such photosensitizers (in particular AlPcS2) in endocytic vesicles and their subsequent ability to induce a release of the contents of these vesicles - including externally added macromolecules - into the cytosol is the basis for a recent method for macromolecule activation, named photochemical internalization (PCI). PCI has been shown to potentiate the biological activity of a large variety of macromolecules. The comprehension of the mechanisms governing this particular sub-cellular localization could allow the design of better candidates for PCI.
Collapse
Affiliation(s)
- Stéphanie Bonneau
- Université Pierre et Marie Curie, Paris 6, UMR 7033, BioMoCeTi, Paris, F-75005, France.
| | | | | | | |
Collapse
|
9
|
Beeby A, FitzGerald S, Stanley CF. Protonation of Tetrasulfonated Zinc Phthalocyanine in Aqueous Acetonitrile Solution¶. Photochem Photobiol 2007. [DOI: 10.1562/0031-8655(2001)0740566potzpi2.0.co2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
|
10
|
Kunz L, Connelly JP, Woodhams JH, MacRobert AJ. Photodynamic modification of disulfonated aluminium phthalocyanine fluorescence in a macrophage cell line. Photochem Photobiol Sci 2007; 6:940-8. [PMID: 17721592 DOI: 10.1039/b708456k] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Disulfonated aluminium phthalocyanine (AlS(2)Pc) is used experimentally as a photosensitiser for both photodynamic therapy (PDT) and photochemical internalisation (PCI). In this study we have focused on modifications in intracellular photosensitiser localisation and fluorescence intensity in macrophages during and after photoirradiation. Since macrophages are highly abundant in tumour tissue and readily accumulate AlS(2)Pc both in vivo and in vitro, we investigated PDT-induced changes of AlS(2)Pc fluorescence in the murine macrophage cell line J774A.1 using CCD fluorescence imaging microscopy. The distinct intracellular localization disappeared upon red laser irradiation and was replaced by a uniform distribution accompanied by a transient fluorescence intensity increase using higher AlS(2)Pc concentrations, followed by photobleaching after further irradiation. A short period of irradiation was sufficient to induce the intracellular redistribution and intensity increase, which then continued in the dark without further laser irradiation. However in the absence of oxygen no fluorescence intensity increase or redistribution was observed. This finding favours the general assumption of photodynamic destruction of organelle membranes resulting in the observed redistribution of the phthalocyanine. No other long-lived fluorescent photoproducts were observed during irradiation. Under deoxygenated conditions slower photobleaching was observed, and photobleaching quantum yields were estimated under aerated and deoxygenated conditions. The participation of reactive oxygen intermediates (ROS) generated during irradiation was indicated by intracellular oxidation of 2',7'-dichlorodihydrofluorescein to the fluorescent 2',7'-dichlorofluorescein in macrophages. The oxygen dependence of these photomodification processes is relevant to the application of AlS(2)Pc to photochemical internalisation which relies on photosensitiser redistribution in cells upon light exposure.
Collapse
Affiliation(s)
- Lars Kunz
- National Medical Laser Centre, University College London, Charles Bell House, 67-73 Riding House St., London, UK
| | | | | | | |
Collapse
|
11
|
Zimcik P, Miletin M, Musil Z, Kopecky K, Kubza L, Brault D. Cationic azaphthalocyanines bearing aliphatic tertiary amino substituents—Synthesis, singlet oxygen production and spectroscopic studies. J Photochem Photobiol A Chem 2006. [DOI: 10.1016/j.jphotochem.2006.02.022] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
12
|
Mahammed A, Gray HB, Weaver JJ, Sorasaenee K, Gross Z. Amphiphilic corroles bind tightly to human serum albumin. Bioconjug Chem 2005; 15:738-46. [PMID: 15264860 DOI: 10.1021/bc034179p] [Citation(s) in RCA: 143] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Amphiphilic 2,17-bis-sulfonato-5,10,15(trispentafluorophenyl)corrole (2) and its Ga and Mn complexes (2-Ga and 2-Mn) form tightly bound noncovalent conjugates with human serum albumin (HSA). Protein-induced changes in the electronic absorption, emission, and circular dichroism spectra of these corroles, as well as results obtained from HPLC profiles of the conjugates and selective fluorescence quenching of the single HSA tryptophan, are interpreted in terms of multiple corrole:HSA binding sites. High-affinity binding sites, close to the unique tryptophan, are fully occupied at very low concentrations. At biologically relevant HSA concentrations (2-3 orders of magnitude larger than those employed in our studies), all corroles (2, 2-Ga, and 2-Mn) may be considered as fully conjugated.
Collapse
Affiliation(s)
- Atif Mahammed
- Department of Chemistry, Technion - Israel Institute of Technology, Haifa 32,000
| | | | | | | | | |
Collapse
|
13
|
Bonneau S, Morlière P, Brault D. Dynamics of interactions of photosensitizers with lipoproteins and membrane-models: correlation with cellular incorporation and subcellular distribution. Biochem Pharmacol 2004; 68:1443-52. [PMID: 15345334 DOI: 10.1016/j.bcp.2004.06.014] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2004] [Accepted: 06/17/2004] [Indexed: 10/26/2022]
Abstract
The incorporation and subcellular localization of photosensitizers are critical determinants of their efficiency. Here, we correlate these properties with the interactions of photosensitizers with membrane-models and low density lipoproteins (LDL) in acellular systems. Focus was given on dynamics aspects. Two amphiphilic photosensitizers, deuteroporphyrin (DP) and aluminum phthalocyanine sulfonated on two adjacent isoindole units (AlPcS2a) were selected. The phthalocyanine was bound to LDL with an overall association constant around 5 x 10(7)M(-1). Biphasic association kinetics was indicative of two types of sites. The release of the phthalocyanine into the bulk aqueous medium occurred within less than a second. A similar behavior was found previously for deuteroporphyrin although its affinity was somewhat higher (5.5 x 10(8)M(-1)). Both compounds were previously characterized by high affinity for membrane-models and quick exchange with the bulk solution. However, they strongly differed by their rate of transfer through the lipid bilayer, in the range of seconds for the porphyrin, several hours for the phthalocyanine. In the case of the porphyrin, fluorescence microscopy on human fibroblasts showed diffuse labeling with no significant modification of the distribution upon vectorization by LDL. In contrast, the phthalocyanine was localized in intracellular vesicles. Vectorization by LDL favored lysosomal localization although little effect was found on the overall uptake as shown by extraction experiments. The role of lipoproteins in the cellular localization of photosensitizers is significantly more important for photosensitizers not freely diffusing through bilayers. The dynamics of the interactions of photosensitizers with membranes appears as an important determinant of their subcellular localization.
Collapse
Affiliation(s)
- Stéphanie Bonneau
- Laboratoire de Physicochimie Biomoléculaire et Cellulaire, Université Pierre et Marie Curie, CNRS UMR 7033, 75005 Paris, France
| | | | | |
Collapse
|
14
|
Saltsman I, Mahammed A, Goldberg I, Tkachenko E, Botoshansky M, Gross Z. Selective substitution of corroles: nitration, hydroformylation, and chlorosulfonation. J Am Chem Soc 2002; 124:7411-20. [PMID: 12071750 DOI: 10.1021/ja025851g] [Citation(s) in RCA: 138] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
This work demonstrates the feasibility and power of electrophilic substitution on the peripheral carbon atoms of triarylcorroles as a synthetic tool to new derivatives. The large difference in the reactivity of the various carbon atoms on the macrocycle was shown to be of electronic rather than steric origin. A careful choice of reagents and a delicate control of reaction conditions allowed the selective syntheses of novel derivatives, in all of which substitution took place selectively in only the directly joined pyrrole rings of the macrocycle. This was proven by a combination of X-ray crystallography of the various products and detailed analysis of their NMR spectra.
Collapse
Affiliation(s)
- Irena Saltsman
- Department of Chemistry and Institute of Catalysis Science and Technology, Technion - Israel Institute of Technology, Haifa 32000, Israel
| | | | | | | | | | | |
Collapse
|
15
|
Lacey JA, Phillips D. Fluorescence lifetime measurements of disulfonated aluminium phthalocyanine in the presence of microbial cells. Photochem Photobiol Sci 2002; 1:378-83. [PMID: 12856705 DOI: 10.1039/b108831a] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The fluorescence lifetimes of disulfonated aluminium phthalocyanine (AlPcS2) in the presence of several different microbial cells are measured using the technique of time correlated single photon counting (TCSPC) employing front-face illumination. The microbes studied are: Escherichia coli, Porphyromonas gingivalis (Gram-negative bacteria), Streptococcus mutans (a Gram-positive bacterium), and the yeast Candida albicans. Complex fluorescence decays are observed when AlPcS2 is in the presence of these microbes; the fluorescence decay data can be fitted to a distribution of exponential lifetimes indicating that the AlPcS2 molecules experience a range of micro-environments The average fluorescence lifetimes of AlPcS2 in the presence of the microbes studied range from 4.85 to 5.95 ns, indicating differences in the cellular localisation of AlPcS2 with each of the microbes studied. These novel data are presented alongside a brief summary of existing AlPcS2 fluorescence lifetime data measured both in solution and in model biological systems.
Collapse
Affiliation(s)
- Jackie A Lacey
- Department of Chemistry, Imperial College of Science, Technology and Medicine, London, UK
| | | |
Collapse
|
16
|
Mahammed A, Goldberg I, Gross Z. Highly selective chlorosulfonation of tris(pentafluorophenyl)corrole as a synthetic tool for the preparation of amphiphilic corroles and metal complexes of planar chirality. Org Lett 2001; 3:3443-6. [PMID: 11678678 DOI: 10.1021/ol0163878] [Citation(s) in RCA: 93] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
[reaction: see text]. The chlorosulfonation of tris(pentafluorophenyl)corrole proceeds with an extremely high selectivity as to afford one out of 139 possible isomers in very high yield. The bis-chlorosulfonated corrole is an excellent precursor to the planar-chirality (triphenylphosphine)cobalt(III) complex (fully characterized by X-ray crystallography) and to the amphiphilic bis-sulfonic acid derivative, both the first of their kind.
Collapse
Affiliation(s)
- A Mahammed
- Department of Chemistry and Institute of Catalysis Science and Technology, Technion-Israel Institute of Technology, Haifa 32000, Israel
| | | | | |
Collapse
|
17
|
Beeby A, FitzGerald S, Stanley CF. Protonation of tetrasulfonated zinc phthalocyanine in aqueous acetonitrile solution. Photochem Photobiol 2001; 74:566-9. [PMID: 11683036 DOI: 10.1562/0031-8655(2001)074<0566:potzpi>2.0.co;2] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The phenomenon of protonation of phthalocyanines (Pc) and its effect upon their photophysical properties has seen considerable neglect in the literature. The work reported here clearly shows that tetrasulfonated zinc Pc, a known photodynamic therapy (PDT) agent, is strongly susceptible to protonation at the azomethine bridges. Absorption and fluorescence spectra demonstrate the absolute dependence of the redshifted peak on the pH of the solution. The fluorescence spectra and lifetimes of the protonated Pc are reported, and the potential application of this phenomenon to the development of a PDT agent with increased selectivity is discussed.
Collapse
Affiliation(s)
- A Beeby
- Department of Chemistry, University of Durham, South Road, Durham DH1 3LE, UK.
| | | | | |
Collapse
|
18
|
Oldham TC, Phillips D, MacRobert AJ. Attempts to measure sensitiser photophysics in opaque tissue. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY. B, BIOLOGY 2001; 61:129-36. [PMID: 11535412 DOI: 10.1016/s1011-1344(01)00176-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Diffuse reflectance laser flash photolysis has been used in an attempt to measure transient triplet spectra of the sensitisers, disulphonated aluminium phthalocyanine and porphyrin IX (derived from 5-amino laevulinic acid), in opaque tissue and models. The latter consisted of tissue phantoms; the former included rat liver and red blood cells. In all cases, triplet-triplet absorption spectra with relatively poor signal-to-noise were obtained providing some encouragement in the application of this technique to in vivo studies on photosensitisers.
Collapse
Affiliation(s)
- T C Oldham
- Department of Chemistry, Imperial College of Science, Technology and Medicine, South Kensington, London SW7 2AY, UK
| | | | | |
Collapse
|
19
|
Maman N, Dhami S, Phillips D, Brault D. Kinetic and equilibrium studies of incorporation of di-sulfonated aluminum phthalocyanine into unilamellar vesicles. BIOCHIMICA ET BIOPHYSICA ACTA 1999; 1420:168-78. [PMID: 10446300 DOI: 10.1016/s0005-2736(99)00093-0] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The interactions of cis-di-sulfonated aluminum phthalocyanine (PcS(2)Al) with dimyristoylphosphatidylcholine (DMPC) unilamellar vesicles have been investigated by fluorescence spectroscopy. At pH 7.0, PcS(2)Al incorporates into the vesicles with a high affinity constant (2.7x10(6) M(-1), in terms of phospholipid concentration). The fluorescence changes following rapid mixing of PcS(2)Al with vesicles are biphasic. The first phase is attributed to the entry of PcS(2)Al into the vesicles, as deduced from the linear dependence of the rate upon lipid concentration. More surprisingly, this rate is strongly pH dependent with a marked maximum around pH 7.3, a result interpreted in terms of the coordination state of the aluminum ion in aqueous solutions. At this pH, a hydroxide ion neutralizes the residual positive charge of the metal ion that remains unbalanced after coordination by the phthalocyanine cycle. A water molecule is likely to complete the metal coordination sphere. Only this form, PcAl(+)(OH(-))(OH(2)), with an uncharged core is quickly incorporated into the vesicles. The protonation of OH(-) or the deprotonation of the coordinated H(2)O leading to a positively or negatively charged core, respectively, account for the observed pH effect. Studies on the effect of cholesterol addition and exchange of PcS(2)Al between vesicles and albumin all indicate the absence of transfer of the phthalocyanine between the vesicle hemileaflets, a result expected from the presence of the two negatively charged sulfonated groups at the ring periphery. Instead, the slower kinetic phase is likely due to the movement of the phthalocyanine becoming more buried within the outer leaflet upon the loss of the water molecule coordinated to the aluminum ion.
Collapse
Affiliation(s)
- N Maman
- Laboratoires de Photobiologie et de Biophysique, CNRS UMR 8646, INSERM U. 201, Muséum National d'Histoire Naturelle, 43 rue Cuvier, 75005, Paris, France
| | | | | | | |
Collapse
|
20
|
Foley MS, Beeby A, Parker AW, Bishop SM, Phillips D. Excited triplet state photophysics of the sulphonated aluminium phthalocyanines bound to human serum albumin. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY. B, BIOLOGY 1997; 38:10-7. [PMID: 9134751 DOI: 10.1016/s1011-1344(96)07434-9] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The binding of the sulphonated aluminum phthalocyanines to human serum albumin (HSA) in aqueous phosphate buffer solution at 25 degrees C has been studied by measuring the properties of the triplet excited states of these dyes. The triplet lifetimes were measured by triplet-triplet absorption flash photolysis. The triplet lifetime of the disulphonated AlS2Pc (2.5 microM) varies from 500 +/- 30 microseconds in the absence of protein to 1.100 microseconds and longer with HSA concentrations above 100 microM. Under identical conditions, the maximum triplet lifetimes of the mono-, tri- and tetrasulphonated compounds bound to HSA are shorter than those for the disulphonated species. The increase in the triplet state lifetimes is attributed to the ability of the bulk aqueous phase to interact with the sensitizer at the site of binding; the site of binding being dependent on the degree of sulphonation. For AlS2Pc and AlS3Pc at all HSA concentrations, and regardless of the degree of sulphonation, all the triplet state decay profiles follow simple pseudo-first-order kinetics. The exponential decay of the triplet phthalocyanine at all HSA concentrations is ascribed to the rapid association and dissociation of the phthalocyanine-HSA complex on the time-scales of the triplet state lifetimes. A simplified one-step binding model is utilized to describe the results. The association of AlS1Pc with HSA results in substantial quenching of the triplet state quantum yield, and a more complex model is required to analyze the results. The tetrasulphonated compound (AlS4Pc) binds to the protein at a site where it experiences some protection from the aqueous phase.
Collapse
Affiliation(s)
- M S Foley
- Department of Physical Chemistry, Imperial College, London, UK
| | | | | | | | | |
Collapse
|
21
|
Foley MS, Beeby A, Parker AW, Bishop SM, Phillips D. Photophysics of disulphonated aluminium phthalocyanine in reverse micelles of Aerosol OT. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 1997. [DOI: 10.1016/s1011-1344(96)07435-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
|
22
|
Dhami S, Rumbles G, MacRobert AJ, Phillips D. Comparative photophysical study of disulfonated aluminum phthalocyanine in unilamellar vesicles and leukemic K562 cells. Photochem Photobiol 1997; 65:85-90. [PMID: 9066287 DOI: 10.1111/j.1751-1097.1997.tb01881.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The photophysical properties of cis-disulfonated aluminum phthalocyanine (AlPcS2) in unilamellar vesicles (liposomes) of DL-alpha-dipalmitoyl-phosphatidylcholine have been measured. Both the fluorescence and triplet quantum yields decreased with increasing sensitizer concentration. The time-resolved fluorescence decays, analyzed by both the sum of exponentials and decay time distribution analyses, are compared with those reported for AlPcS2 in leukemic K562 cells. Information on the photodynamic transport and localization mechanism has been obtained by drawing correlations between the two systems, indicating active transport of the phthalocyanine into tumor cells involving lysosomal accumulation.
Collapse
Affiliation(s)
- S Dhami
- Department of Chemistry, Imperial College of Science, Technology & Medicine, London, UK
| | | | | | | |
Collapse
|
23
|
Comparison of the photophysics of an aggregating and non-aggregating aluminium phthalocyanine system incorporated into unilamellar vesicles. J Photochem Photobiol A Chem 1996. [DOI: 10.1016/s1010-6030(96)04438-3] [Citation(s) in RCA: 92] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
|
24
|
Kleemann D, MacRobert AJ, Mentzel T, Speight PM, Bown SG. Photodynamic therapy on the normal rabbit larynx with phthalocyanine and 5-aminolaevulinic acid induced protoporphyrin IX photosensitisation. Br J Cancer 1996; 74:49-58. [PMID: 8679457 PMCID: PMC2074606 DOI: 10.1038/bjc.1996.314] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Photodynamic therapy (PDT) is a promising technique for the treatment of small tumours in organs where it is essential to minimise damage to immediately adjacent normal tissue as PDT damage to many tissues heals by regeneration rather than scarring. As preservation of function is one of the main aims of treating laryngeal tumours, this project studied the effects of PDT on the normal rabbit larynx with two photosensitisers, endogenous protoporphyrin IX (PPIX) induced by the administration of 5-aminolaevulinic acid (ALA) and disulphonated aluminium phthalocyanine (AIS2Pc). The main aims of the study were to examine the distribution of protoporphyrin IX and AIS2Pc by fluorescence microscopy in the different regions of the larnyx and to assess the nature and subsequent healing of PDT damage. Peak levels of PPIX were found 0.5-4 h after administration of ALA (depending on dose) with highest levels in the epithelium of the mucosa. With 100 mg kg-1, PDT necrosis was limited to the mucosa, whereas with 200 mg kg-1 necrosis extended to the muscle. With 1 mg kg-1 AIS2Pc, 1 h after administration, the drug was mainly in the submucosa and muscle, whereas after 24 h, it was predominantly in the mucosa. PDT at 1 h caused deep necrosis whereas at 24 h it was limited to the mucosa. All mucosal necrosis healed by regeneration whereas deeper effects left some fibrosis. No damage to cartilage was seen in any of the animals studied. The results of this study have shown that both photosensitisers are suitable for treating mucosal lesions of the larynx, but that for both it is important to optimise the drug dose and time interval between drug and light to avoid unacceptable changes in normal areas.
Collapse
Affiliation(s)
- D Kleemann
- National Medical Laser Centre, University College London Medical School
| | | | | | | | | |
Collapse
|
25
|
Nyamekye I, Buonaccorsi G, McEwan J, MacRobert A, Bown S, Bishop C. Inhibition of intimal hyperplasia in balloon injured arteries with adjunctive phthalocyanine sensitised photodynamic therapy. Eur J Vasc Endovasc Surg 1996; 11:19-28. [PMID: 8564482 DOI: 10.1016/s1078-5884(96)80130-4] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
OBJECTIVES We investigated the effects of Photodynamic therapy (PDT) using Aluminium disulphonated phthalocyanine (AlS2Pc) on experimental intimal hyperplasia (FCIH). MATERIALS AND METHODS (a) Pharmacokinetics: Normal rats were injected with Als2Pc and carotid artery fluorescence was measured. (b) Normal artery PDT: Sensitised rats underwent carotid artery laser irradiation (50J/cm2, 675nm) and were assessed after 3 and 14 days and 1-6 months. (c) PDT: Rats underwent standard carotid artery balloon injury immediately prior to PDT and arteries were assessed at 2 to 26 weeks, together with laser, AlS2Pc, and untreated controls. CHIEF OUTCOME MEASURES (a) Fluorescence intensity in different arterial layers. (b) Medial smooth muscle cell counts per high power field (light microscopic). (c) Percentage amount of FCIH (area of intimal hyperplasia) as a ratio of the IEL (area enclosed by the internal elastic lamina). RESULTS (a) AlS2Pc fluorescence intensity increased with increasing dosage, with maximal fluorescence in the arterial media at 30 min. (b) PDT produced medial cell depletion at 3 days and persisted over 6 months without loss of vessel integrity. (c) PDT completely inhibited FCIH at 2 and 4 weeks. This was partial at 6 to 26 weeks (51% of untreated level). PDT inhibition of FCIH was significantly greater than in any of the control groups. p < 0.0001. Mann-Whitney Test. CONCLUSION Adjunctive AlS2Pc sensitised photodynamic therapy inhibits experimental intimal hyperplasia, by causing medial smooth muscle cell depletion. This offers a new approach to the management of angioplasty restenosis in patients.
Collapse
Affiliation(s)
- I Nyamekye
- Department of Surgery, University College London Medical School, Rayne Institute, U.K
| | | | | | | | | | | |
Collapse
|
26
|
Zuk MM, Kenney ME, Horowitz B, Ben-Hur E. High-performance liquid chromatographic determination of the silicon phthalocyanine Pc 4 in human blood. JOURNAL OF CHROMATOGRAPHY. B, BIOMEDICAL APPLICATIONS 1995; 673:320-4. [PMID: 8611969 DOI: 10.1016/0378-4347(95)00272-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
A sensitive and reproducible method has been developed for the measurement of the silicon phthalocyanine Pc 4 in red blood cell concentrates (RBCC). The procedure involves extraction of the RBCC with acetonitrile, purification of the extracts with reversed-phase Sep-Pak C18 cartridges and determination of Pc 4 in the extracts by high-performance liquid chromatography (HPLC) using a reversed-phase C18 column. The detection limit with 1-ml RBCC samples is 2 ng. This method is applicable to monitoring Pc 4 during its use as a photosensitizer for the inactivation of viruses in RBCC prior to transfusion. It has the potential to be adapted for measuring Pc 4 in tissues during its use in photodynamic therapy of cancer.
Collapse
Affiliation(s)
- M M Zuk
- New York Blood Center, NY 10021, USA
| | | | | | | |
Collapse
|
27
|
Dhami S, Mello AJD, Rumbles G, Bishop SM, Phillips D, Beeby A. PHTHALOCYANINE FLUORESCENCE AT HIGH CONCENTRATION: DIMERS OR REABSORPTION EFFECT? Photochem Photobiol 1995. [DOI: 10.1111/j.1751-1097.1995.tb08619.x] [Citation(s) in RCA: 169] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|