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1.
Abstract— Zinc phthalocyanines sulfonated to different degrees are tested for their ability to sensitizeV–79 Chinese hamster cells andEMT–6 mouse mammary tumors to red light. In vitro , the lower sulfonated derivatives were the most active with the exception of the poorly water-soluble monosulfonated dye. An isomeric mixture of tetrasulfonated derivatives obtained via direct sulfonation was ten times more active than the homogeneous tetrasulfo derivative prepared via the condensation of sulfophthalic acid. In vivo , the latter dye was completely inactive, whereas the remainder of the sulfonated preparations exhibited a similar structure-activity pattern as observed with theV–79 cells in vitro . The disulfonated zinc phthalocyanine showed the best tumoricidal activity in the series and also appeared to be a more efficient photosensitizer of cell inactivation and tumor cure than the aluminum or gallium complexes as well as hematoporphyrin derivative preparations. No significant differences in skin phototoxicity were observed among the various dyes.  相似文献   

2.
Abstract— The photosensitized oxidation of L-tryptophan by gallium phthalocyanines sulfonated to different degrees is studied as a function of both substrate and sensitizer concentrations in water and 50% MeOH-H2O solutions. The maximum quantum yield of singlet oxygen was found to be nearly 0.5 for all sulfonated gallium complexes. The effect of adding sulfonate groups in the phthalocyanine backbone is to change the tendency of dye molecules to dimerize or aggregate in a particular solvent. A shift in the chemical equilibrium away from the monomeric state, which occurs at high dye concentrations and at lower degrees of dye sulfonation, results in a reduced photochemical yield. The variation of quantum yields in different solvent systems and at several wavelengths is similarly accounted for by the fraction of light absorbed by the productive monomer state.  相似文献   

3.
The photocytotoxicity of sulfonated phthalimidomethyl aluminum phthalocyanine, a more hydrophobic photosensitizer as compared to phthalocyanine substituted with sulfonate groups only, was investigated. Inclusion of 1-2 phthalimidomethyl groups into disulfonated aluminum phthalocyanine, resulted in increased partition coefficients between n-octanol and water, and a six-fold increase in both cellular uptake and photocytotoxicity towards Chinese hamster lung fibroblast cells (line V-79). Reducing the number of phthalimidomethyl groups, or increasing the degree of sulfonation, lead to a decrease in the partition coefficient, cellular uptake, and phototoxicity. The quantum yield of singlet oxygen was comparable for all dyes tested in this series, indicating that no significant change in this photophysical parameter resulted from phthalimidomethylation. These results suggest that the addition of 1-2 phthalimidomethyl groups to disulfonated aluminum phthalocyanine improves cellular uptake, but, as the relative efficiency of cell killing was not effected, the intracellular distribution on photosensitive molecules may not be modified.  相似文献   

4.
Six sulfonated metallophthalocyanines, chelated with either aluminum or zinc and sulfonated to different degrees, were studied in vivo for their photodynamic activity in a rat skin-fold chamber model. The chamber, located on the back of female WAG/Rij rats, contained a syngeneic mammary carcinoma implanted into a layer of subcutaneous tissue. Twenty-four hours after intravenous administration of 2.5 μmol/kg of one of the dyes, the chambers received a treatment light dose of 600 J/cm2 with monochromatic light of 675 nm at a power density of 100 mW/ cm2. During light delivery and up to a period of 7 days after treatment, vascular effects of tumor and normal tissue were scored. Tumor cell viability was determined by histology and by reimplantation of the chamber contents into the skin of the same animal, either 2 h after treatment or after the 7 day observation period. Vascular effects of both tumor and subcutaneous tissue were strongest with dyes with the lowest degree of sulfonation and decreased with increasing degree of sulfonation. Tumor regrowth did not occur with aluminum phthalocyanine mono- and disulfonate and with zinc phthalocyanine monosulfonate. With the protocol that was used, complete necrosis without recovery was only observed when reimplantation took place at the end of the 7 day follow-up period. Reimplantation 2 h after treatment always resulted in tumor regrowth. At this interval, the presence of viable tumor cells was confirmed histologically. In general tumor tissue vasculature was more susceptible to photodynamic damage than vasculature of the normal tissue. The effect on the circulation of both tumor and normal tissue increased with decreasing degree of sulfonation. Based on this study, the photodynamic effects using the six sulfonated metallophthalocyanines on the vasculature can be ranked from high to low as: AlPcS2= ZnPcS1 > AIPcS1 > AIPcS4 > ZnPcS2 > ZnPcS4.  相似文献   

5.
研究了高交联大孔苯乙烯-二乙烯本共聚物在有溶胀剂和无溶胀剂条件下,反应温度、 反应时间及共聚物合成时所用致孔剂对其磺化反应的影响.结果显示,当磺化反应在不同溶胀 剂介质中进行时,共聚物的交换容量随交联度变化可是现不同的关系.与低交联大孔共聚物(交 联度7%)比较,高文联大孔共聚物(交联度60%)磺化反应速度更快,反应能在低得多的温度下 进行,同时溶胀介质对磺化产物的交换容量的影响变得很小.60%交联的共聚物于35C反应3h, 可获得接近于表面磺化的产物.  相似文献   

6.
A novel polyetheretherketone (PEK-C) prepared from phenolphthalein has been synthesized. In order to improve some of its properties for application in high performance membrane, the PEK-C has been sulfonated with concentrated sulfuric acid. Degree of sulfonation can be regulated by controlling the temmperature and time of sulfonation. The characterization of the sulfonated PEK-C in sodium salt form has been made by IR, ~1H NMR and ~(13)C NMR etc. It is shown that the sulfonation appears to take place exclusively in the ortho position to phenolic ether of phenolphthalein unit. The result is in agreement with theoretical deduction. Some properties of the sulfonated PEK-C, such as solubility, transition temperature, thermal degradation and hydrophilicity have also been discussed.  相似文献   

7.
以壳聚糖为基材,分别以氯磺酸、三甲胺.三氧化硫和丙磺酸内酯为磺化试剂,制备了3,6-O-磺化壳聚糖(OCS)、2-N-磺化壳聚糖(NCS)和2-N-磺丙基壳聚糖(PCS)3种磺化壳聚糖.采用红外光谱、核磁共振谱证明了磺化壳聚糖的结构,元素分析测定了磺化壳聚糖的磺化率.以组织修复过程中一种重要的活性因子——碱性成纤维细胞生长因子(bFGF)为目标因子,通过体外成纤维细胞培养实验,评价了不同磺化壳聚糖对bFGF活性的保护能力.结果显示,相对于未改性壳聚糖(CS),磺化壳聚糖对成纤维细胞的形态无显著影响.细胞活性检测结果显示,OCS和PCS对bFGF活性无明显的保护能力;NCS能有效提高bFGF促进成纤维细胞活性的能力,其对bFGF活性的保护能力可达肝素70%左右.磺化壳聚糖的bFGF活性保护能力不随磺化率的改变而变化.  相似文献   

8.
采用激基缔合物荧光光谱法研究了轻度磺化聚甲基丙烯酸丁酯-b-聚苯乙烯(PBMA-b-PSt)嵌段离聚体在极性溶剂N,N-二甲基甲酰胺(DMF)溶液中的聚集行为;发现嵌段离聚体的磺化度和浓度强烈影响溶液中聚合物链的聚集态结构,不同的磺化度样品具有不同的临界聚集浓度;随磺化度增加,聚合物链缠绕密集,形成具有多苯环的聚集体,而且当磺化度为摩尔分数x=3.59%时,荧光发射光谱最大发射峰波长出现最大红移,临界聚集浓度最低,说明最容易形成多苯环聚集体,该磺化点可以认为是磺化聚甲基丙烯酸丁酯-b-聚苯乙烯体现离聚体行为和聚电解质行为的临界磺化度。  相似文献   

9.
For the utilization of product from wood liquefaction by ionic liquid, the liquefied product was sulfonated by chlorosulfonic acid as a sulfonating agent, and the product of wood liquefaction sulfonation (WLS) was obtained. The characterization of WLS is determined using FTIR, and the strong absorption peak of sulfonic group is clear. The suitable reaction conditions are as follows, the mass ratio of chlorosulfonic acid to liquefied wood and formaldehyde to liquefied wood are 0.8:1 and 0.9:1, reaction temperature of sulfonation and condensation are at 85°C and 90°C, reaction time of sulfonation and condensation are for 2.5 and 3.0 hours. When the solution concentration of WLS is 15 g · L?1, the surface tension is 46.9 mN · m?1. In the formula of seed coating agent, WLS shows better suspension property and less change of viscosity in impact test than that of conventional surfactants, also, it can generate synergy effects with the other surfactants to make higher suspending rate in binary or ternary mixed system than that in single system.  相似文献   

10.
The sulfonated polyetherimide (sPEI) was synthesized by direct sulfonation method using chlorosulfonic acid as a sulfonating agent. Different sulfonation degrees of sPEI was obtained by varying the ratio of PEI to chlorosulfonic acid and reaction time. Then, sulfonated polyetherimide was blended with polyethylene glycol (PEG) and thermally cross-linked in order to achieve high performance proton exchange membrane. It was found that the addition of PEG resulted in a significant increase in porosity and water uptake of the membranes, which favored proton transport at low temperature. The maximum proton conductivity was 11 mS/cm at 75°C for the blend membrane containing 20% PEG. The sulfonation and blend modification of PEI were characterized by attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy.  相似文献   

11.
We prepared sulfonated polyphosphazenes having various aryloxy substituents, and studied their thermal stabilities and membrane properties. Sulfonated polyphosphazenes were synthesized by the reaction of polydichlorophosphazene with sodium aryloxides and subsequent sulfonation with fuming sulfuric acid. With increasing the degree of sulfonation, the polymers showed higher proton conductivity, but suffered more from swelling in an aqueous solution. We introduced a hydroxymethylphenoxy group onto the phosphazene backbone as a self‐crosslinkable group by reaction of poly(dichlorophosphazene) and a sodium salt of 4‐hydroxymethylphenol. When a film of a sulfonated polymer having a methylol group was heated at 80 °C under vacuum for 1 h, it became insoluble in NMP, indicating the formation of a network structure. We investigated the crosslinking reaction of the polymers by DSC and FTIR. The crosslinking reaction proceeded only in the sulfonated polymers. Because the sulfonated polymers provide acidic protons, the methylol groups became more electrophilic and reacted with neighboring aromatic rings. A condensation reaction between themselves could also occur. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 5850–5858, 2008  相似文献   

12.
A novel sulfonated poly(arylene ether) containing triphenylmethane moieties was synthesized by the sulfonation of a designed parent polymer using chlorosulfonic acid as sulfonation agent. The sulfonation took place at the para position of the pendant phenyl rings because of the specially designed parent polymer. The position and degree of sulfonation were characterized by ^1H-NMR and elemental analysis. The sulfonated polymers are highly soluble in common organic solvents, such as dimethylsulfoxide, N,N'-dimethylacetamide, dimethylformamide, ethylene glycol monomethyl ether, and can be readily cast into tough and smooth films from solutions. The films showed good thermal and hydrolysis stabilities. Moreover, Fenton's reagent test revealed that the films exhibited superior stability to oxidation. The proton conductivities of the films were comparable with Nation 117 under same conditions. The membrane electrode assembly (MEA) prepared with the asmade film (706 EW, 100 μm dry thickness) shows better cell performance than Nation 115-MEA in the whole current density range.  相似文献   

13.
Poly(ether ketone ketone) was sulfonated using fumic sulfuric acid and used for preparation of proton conductive membranes. The sulfonation degree was evaluated by elemental and thermal analysis and the IEC values were determined by titration. The proton conductivity of membranes with sulfonation degrees up to 70% was determined as a function of temperature by impedance spectroscopy. Membranes with sulfonation degree 38–70% were tested in DMFC experiments. Their performance was comparable to Nafion® with the same pretreatment and clearly better than sulfonated poly(ether ether ketone) membranes with similar functionalization. The methanol crossover was lower than that of Nafion® in the same conditions.  相似文献   

14.
Multiblock sulfonated poly(arylene ether sulfone)s were synthesized to investigate the structural effects on their membrane properties. Three different types of sulfonated hydrophilic blocks were used; their structures possessed different acidity and local concentration of sulfonic acid groups. For the comparison between the block copolymers, a hydrophobic block with the same chemical structure and block length was used. The different acidities and local concentration were achieved using different sulfonation methods, such as postsulfonation and direct condensation with sulfonated monomers, and different monomers for preparing the hydrophilic block. The higher acidity and concentration of sulfonic acid groups resulted in higher proton conductivity under certain relative humidity conditions and phase separation as shown in the transmission electron microscopy analysis. The synthesized oligomers and polymers were well characterized, and the other physical properties were also investigated. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 2947–2957  相似文献   

15.
磺化间规聚苯乙烯的表征   总被引:4,自引:0,他引:4  
间规聚苯乙烯(sPS)是一种新型结晶性工程塑料,熔点达270℃,具有结晶速度快、耐热性好、耐化学腐蚀性优良等特点,可广泛用于汽车、电子、机械等行业,极具开发意义,但是由于sPS脆性大,抗冲击性差,故通过化学改性在sPS的苯环上引入极性基团,用于制成共混合金与复合材料,是提高材料韧性,开拓sPS用途的重要途径。  相似文献   

16.
17.
The biodistribution and metabolism of 14C-labeled disulfonated and trisulfonated gallium phthalocyanine (Ga-PcS) was studied in radiation-induced fibrosarcoma tumor-bearing C3H mice. The [14C]Ga-PcS compounds were prepared via the condensation of [14C]phthalic acid and sulfophthalic acid in the presence of gallium chloride and characterized by their spectroscopic and chromatographic properties. The tissue concentrations of the dyes was measured by scintillation counting of the 14C and by extraction and fluorescence measurements. Elevated dye levels were found in the liver, lungs, kidneys and spleen as well as in the tumor. Lower sulfonation of Ga-PcS favored liver and spleen uptake whereas higher dye sulfonation resulted in greater kidney uptake. Both dyes showed high tumor uptake with peak concentrations exceeding those of most tissues except for the liver in the case of Ga-PcS2. The highest tumor uptake was observed with Ga-PcS3. Both dyes were slowly excreted from the body. The liver-feces pathway was favored in the case of Ga-PcS2 with high activities persisting in the liver, even after 21 days. The Ga-PcS3 was preferentially excreted via the kidney-urine pathway. High performance liquid chromatography analysis of the liver and tumor extracts of [14C]Ga-PcS3-treated animals did not reveal desulfonation of the dye. However, urine analysis showed the presence of radioactive metabolites lacking the characteristic phthalocyanine absorption.  相似文献   

18.
The photosensitive multilayer films from sulfonated metal-free, sulfonated copper-, and sulfonated nickel-phthalocyanines were fabricated with diazoresin layer by layer on a substrate via electrostatic interaction by the self-assembly technique. Under UV irradiation, the linkage nature between the layers of the film is converted from the electrostatic bonding to covalent bonding. The covalently attached multilayer films are very stable towards polar solvents and salt aqueous solutions. The photovoltaic properties of the covalently attached film can be determined by means of a traditional three-electrode photoelectrochemical cell in aqueous solutions with KCI as the supporting electrolyte. The photocurrent determination has shown that the sulfonated copper-containing phthalocyanine films possess a higher photocurrent value than sulfonated metalfree and sulfonated nickel-containing phthaloeyanine films.  相似文献   

19.
A novel sulfonated poly(arylene ether) containing tetraphenylmethane moieties was successfully synthesized by the sulfonation of a designed parent polymer using chlorosulfonic acid as sulfonation agent. The sulfonation took place only at the para position on the pendant phenyl rings because of the specially designed parent polymer. The sulfonation degree can be easily controlled by using different ratios of sulfonation agent to polymer repeating unit. The position and degree of sulfonation were characterized by 1H NMR and elemental analysis. The sulfonated polymers are highly soluble in common organic solvents, such as dimethylsulfoxide, N,N′‐dimethylacetamide, dimethylformamide, ethylene glycol monomethyl ether, and can be readily cast into tough and smooth films from solutions. The films showed good thermal and hydrolysis stabilities. Moreover, Fenton's reagent test revealed that the membrane exhibited superior stability to oxidation. The proton conductivities of the films were determined to be equivalent with Nafion® 117 under same conditions. The new polymer with sulfonic acid function on pendent phenyl rings can be potentially used as a proton‐exchange membrane for polymer electrolyte membrane fuel cell. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 6411–6418, 2005  相似文献   

20.
This work focuses on the understanding of the electrophoretic behavior of flexible chains of polystyrenesulfonates (PSSs) in free solution. It deals mainly with the variation of the electrophoretic mobility with (i) the polymerization degree (N) of fully sulfonated PSSs and (ii) the sulfonation rate of randomly sulfonated PSSs. In both cases, the electrophoretic mobility was modeled following a semi-empirical approach which involves parameters retaining a physical meaning. Fully sulfonated PSS oligomers, having a length smaller than or similar to the Debye length, exhibit a particular electrophoretic behavior, in-between that observed for multicharged small molecules and that for polyelectrolytes. The electrophoretic mobility of these oligomers increases strongly with N, which is attributed to a hydrodynamic coupling between monomers. Then the mobility is maximum for an N of about 10, for which the PSS oligomers are still in a rod-like conformation. Afterwards, as N increases and the PSSs are larger than the Debye length, the electrophoretic mobility decreases slowly until it reaches a constant value corresponding to the free-draining behavior. Next, the electrophoretic behavior of long PSS (N about 1,200) differing in their sulfonation rates was investigated. The effective charge rates were determined independently by conductimetric measurements and the mobilities were modeled as a function of the sulfonation rate. The PSS behavior observed was compared to the one previously reported for classical polyelectrolytes having hydrophilic backbones, such as copolymers of poly(acryamide-coacrylic acid). A specific behavior has been pointed out for these partially sulfonated PSSs, which is attributed to the hydrophobicity of their backbone. Finally, it is shown that separations of PSSs of different sulfonation rates can be obtained with electrolytes containing an anionic surfactant or methanol.  相似文献   

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