Photodynamic Effects of Zinc(II) Phthalocyanine‐Loaded Polymeric Micelles in Human Nasopharynx KB Carcinoma Cells

A major difficulty in photodynamic therapy is the poor solubility of the photosensitizer (PS) under physiological conditions which correlates with low bioavailability. PS aggregation leads to a decrease in the photodynamic efficiency and a more limited activity in vitro and in vivo. To improve the aqueous solubility and reduce the aggregation of 2,9(10),16(17),23(24)‐tetrakis[(2‐dimethylamino)ethylsulfanyl]phthal‐ocyaninatozinc(II) (Pc9), the encapsulation into four poloxamine polymeric micelles (T304, T904, T1107 and T1307) displaying a broad spectrum of molecular weight and hydrophilic–lipophilic balance was investigated. The aqueous solubility of Pc9 was increased up to 30 times. Morphological evaluation showed the formation of Pc9‐loaded spherical micelles in the nanosize range. UV/Vis and fluorescence studies indicated that Pc9 is less aggregated upon encapsulation in comparison with Pc9 in water–DMSO 2% and remained photostable. Pc9‐loaded micelles generated singlet molecular oxygen in high yields. Photocytotoxicity assays using human nasopharynx KB carcinoma cells confirmed that the encapsulation of Pc9 in T1107 and T1307 increases its photocytotoxicity by 10 times in comparison with the free form in water–DMSO. In addition, Pc9 incorporated into cells was mainly localized in lysosomes.     

Preparation and photocatalytic activity under visible light irradiation of mesostructured titania particles modified with phthalocyanine in the pores

Mesostructured titania particles modified with phthalocyanine (Pc) were prepared by using molecular self-assemblies of cetyltrimethylammonium bromide (CTAB) with solubilized Pc as a template. Low-angle X-ray diffraction pattern and transmission electron microscopy (TEM) image clearly show the formation of Pc/titania particles with hexagonal mesopore structures. Diffuse reflectance UV–vis spectrum and fluorescence spectrum of Pc/titania indicate that Pc molecules in the pores are in a monomeric state. In addition, Pc/titania particles have photocatalytic activity under visible light irradiation (>610 nm) due to the reduction reaction by the electrons transferred from Pc to titania.     

Faujasite-type zeolites modified with iron perfluorophthalocyanines: Synthesis and characterization

The synthesis and characterization of hexadeca- or perfluorophthalocyanine complexes of iron(II) (FeF₁₆Pc) in synthetic faujasite-type zeolites is reported. The encapsulation of FeF₁₆Pc in NaY zeolite by the template synthesis method as well as the synthesis of NaX around FeF₁₆Pc are discussed. A spectroscopic (UV—VIS, IR) and electrochemical analysis of the modified zeolites, providing evidence for encapsulation, is presented and compared with the unsubstituted FePc complex.     

体积排阻色谱法定量检测9种型别人乳头瘤病毒原液中病毒样颗粒

据统计,5％以上的人类癌症由人乳头瘤病毒(HPV)导致.HPV疫苗的使用,尤其是多价HPV疫苗的使用,可有效预防HPV感染和肿瘤的发生.例如,9价HPV疫苗可有效预防90％以上HPV相关癌前病变.人乳头瘤病毒样颗粒(VLP)是HPV疫苗的唯一抗原.VLP由360份衣壳蛋白L1组成.VLP的含量测定对HPV原液和HPV疫...     

Effective encapsulation of Sudan black B with polystyrene using miniemulsion polymerization

In this study, polystyrene (PS)/Sudan black B (SDB) latex particles were prepared using a miniemulsion polymerization technique in the presence of methyl isobutyl ketone (MIBK). Effects of the weight ratio of MIBK/styrene (St) and the SDB load on the morphology of latex particles and encapsulation efficiency were studied. It was found that the encapsulation efficiency of SDB with PS increased as the weight ratio of MIBK/St rose. The PS/SDB latex particles have a perfect core-shell structure and as high as more than 90% of encapsulation efficiency at 1:1 of MIBK/St. UV irradiation experiments and dynamic light scattering tests indicated that the obtained PS/SDB latexes exhibited excellent photostability and storage stability.     

Relative size selection of a conjugated polyelectrolyte in virus-like protein structures

A conjugated polyelectrolyte poly[(2-methoxy-5-propyloxy sulfonate)-phenyl-ene vinylene] (MPS-PPV) drives the assembly of virus capsid proteins to form single virus-like particles (VLPs) and aggregates with more than two VLPs, with a relative selection of high molecular weight polymer in the latter.     

光敏共聚物P(St/VM-co-MA)自组装胶体粒子及其性能

以苯乙烯类光敏单体7-(4-乙烯基苄氧基)-4-甲基香豆素(VM)、苯乙烯(St)、马来酸酐(MA)为共聚单体,采用自由基聚合法制备了光敏性双亲共聚物P(St/VM-co-MA).在选择性溶剂(N,N-二甲基甲酰胺(DMF)/H2O)中对P(St/VM-co-MA)进行自组装,用透射电镜(TEM)和动态激光光散射(DLS)表征了自组装胶体粒子的形态、粒径大小及其分布.利用紫外光照使胶体粒子中香豆素基元发生光二聚反应,形成交联胶体粒子,并用紫外-可见光分光光度计(UV-Vis)跟踪其交联过程.用DLS研究了交联和未经交联胶体粒子的粒径和结构稳定性,用激光扫描共聚焦显微镜(LSCM)和光学显微镜考察了胶体粒子的乳化、包覆性能.结果表明:交联和未经交联胶体粒子均具有乳化性,且在乳化过程中可实现对油溶性染料的包覆.胶体粒子交联后,粒径有所减小,结构稳定性、乳化性能、包覆性能均有所提高.     

Functional virus-based polymer-protein nanoparticles by atom transfer radical polymerization

Viruses and virus-like particles (VLPs) are useful tools in biomedical research. Their defined structural attributes make them attractive platforms for engineered interactions over large molecular surface areas. In this report, we describe the use of VLPs as multivalent macroinitiators for atom transfer radical polymerization. The introduction of chemically reactive monomers during polymerization provides a robust platform for post-synthetic modification via the copper-catalyzed azide-alkyne cycloaddition reaction. These results provide the basis to construct nanoparticle delivery vehicles and imaging agents using protein-polymer conjugates.     

The Relationship of Phthalocyanine 4 (Pc 4) Concentrations Measured Noninvasively to Outcome of Pc 4 Photodynamic Therapy in Mice

The ability to noninvasively measure photosensitizer concentration at target tissues will allow optimization of photodynamic therapy (PDT) and could improve outcome. In this study, we evaluated whether preirradiation tumor phthalocyanine 4 (Pc 4) concentrations, measured noninvasively by the optical pharmacokinetic system (OPS), correlated with tumor response to PDT. Mice bearing human breast cancer xenografts were treated with 2 mg kg⁻¹ Pc 4 iv only, laser irradiation (150 J cm⁻²) only, Pc 4 followed by fractionated irradiation or Pc 4 followed by continuous irradiation. Laser irradiation treatment was initiated when the tumor to skin ratio of Pc 4 concentration reached a maximum of 2.1 at 48 h after administration. Pc 4 concentrations in tumor, as well as in Intralipid in vitro , decreased monoexponentially with laser fluence. Pc 4-PDT resulted in significant tumor regression, and tumor response was similar in the groups receiving either fractionated or continuous irradiation treatment after Pc 4. Tumor growth delay following Pc 4-PDT correlated with OPS-measured tumor Pc 4 concentrations at 24 h prior to PDT ( R ² = 0.86). In excised tumors, OPS-measured Pc 4 concentrations were similar to the HPLC-measured concentrations. Thus, OPS measurements of photosensitizer concentrations can be used to assist in the scheduling of Pc 4-PDT.     

INACTIVATION OF Trypanosoma cruzi TRYPOMASTIGOTE FORMS IN BLOOD COMPONENTS BY PHOTODYNAMIC TREATMENT WITH PHTHALOCYANINES

Abstract— -Three phthalocyanine dyes HOSiPcOSi(CH₃)₂(CH₂)₃N(CH₃)₂ (Pc 4), HOSiPc-OSi(CH₃)₂(CH₂)₃N+(CH₃)3I- (Pc 5) and aluminum tetrasulfophthalocyanine hydroxide (AlOHPcS₄) were evaluated for their ability to inactivate the trypomastigote form of Trypanosoma cruzi in fresh frozen plasma (FFP) and red blood cell concentrates (RBCC). The compound Pc 4 was found to be highly effective in killing T. cruzi, Pc 5 less effective and AlOHPcS₄ ineffective. With FFP as the medium, a complete loss of parasite infectivity in vitro (≥5 log₁₀) was found to occur with 2 μ M Pc 4 after irradiation with red light (>600 nm) at a fiuence of 7.5 J/cm², while with RBCC as the medium, a complete loss was found to occur at a fiuence of 15 J/cm². Even without illumination, Pc 4 at 2 μ M also killed about 3.7-4.1 log₁₀ of T. cruzi in FFP during 30 min. Observed differences in T. cruzi killing by the various phthalocyanines may relate to differences in binding; Pc 4 binds to the parasites about twice as much as Pc 5. Ultrastructural analysis of treated parasites suggests that mitochondria are a primary target of this photodynamic treatment. The data indicate that Pc 4 combined with exposure to red light could be used to eliminate bloodborne T. cruzi parasites from blood components intended for transfusion. The inactivation of T. cruzi by Pc 4 in the dark suggests a possible therapeutic application.     

Photovoltaic and electrocatalytic properties of novel ball-type phthalocyanines bridged with four dicumarol

The new ball-type metallo bisphthalocyanines (Co(2)Pc(2) and Zn(2)Pc(2)) were synthesized from the corresponding [4,4'-bis(dicoumaroylphthalonitrile)] which can be obtained from the reaction of 3,3'-methylenebis(4-hydroxy-2H-chromen-2-one) and 4-nitrophthalonitrile. The structures of the newly synthesized compounds have been confirmed and characterized by elemental analysis, UV/Vis, IR and (1)H NMR spectroscopies and MALDI-TOF mass spectrometry. Solar cells of the configuration ITO/Co(2)Pc(2)/C60/Al and ITO/Zn(2)Pc(2)/C60/Al were fabricated. The effect of the thickness of the active Pc layer--the thickness of the Pc layer was varied from 15 to 80 nm--on solar cells parameters has been investigated. A nearly thickness independent open circuit voltage was observed in both structures. The maximum photovoltaic conversion efficiency, short circuit current and fill factor were observed in ITO/Zn(2)Pc(2)/C60/Al cell with 80 nm Pc layer to be 0.255%, 1 mA cm(-2) and 0.38, respectively. The redox properties of the ball-type complexes were investigated by cyclic voltammetry, controlled-potential coulometry and in situ spectroelectrochemistry in DMSO-TBAP. The electrochemical measurements showed that the complexes form ring-based and/or metal-based mixed-valence species, due to the remarkable intramolecular interactions between the two metal phthalocyanine units. The Vulcan XC-72(VC)/Nafion(Nf)/Co(2)Pc(2) modified glassy carbon electrode showed much higher catalytic performance towards oxygen reduction, compared to the VC/Nf/Zn(2)Pc(2) modified one. It was found that the VC/Nf/Co(2)Pc(2) catalyst is nearly insensitive to the presence of methanol. In the presence of 1 M methanol in the electrolyte, the catalytic performance of the Co(2)Pc(2)-based catalyst in oxygen reduction was much better than that of the Pt-based one. Thus, it was shown that the VC/Nf/Co(2)Pc(2) catalyst can be a good alternative to VC/Nf/Pt as a cathode catalyst in direct methanol fuel cells.     

Chitosan Encapsulation of Poly(n-butyl acrylate-co-methyl methacrylate) Particles

Poly(n-butyl acrylate-co-methyl methacrylate) particles encapsulated with chitosan were synthesized at 1:1 monomer ratio using potassium persulfate as an initiator. Effect of concentration and molecular weight of chitosan on particle encapsulation process was investigated. Chitosan concentration was varied from 0.5%, 1%, and 1.5% w/v, while molecular weights were 120, 370, and 850 kDa, respectively. The results showed that the particle diameter of the copolymer particles with chitosan encapsulation was increased when the concentration and molecular weight of chitosan were increased. The average particle size and zeta potential were obtained in a range of 144–625 nm and +27 – +47 mV, respectively. TEM micrographs suggested a presence of the chitosan encapsulation layer on the particles.     

Comparison of the preparation of PLGA–BSA nano- and microparticles by PVA, poloxamer and PVP

The objective of our study was to prepare nano- and microparticles economically considering some practical parameters such as size and encapsulation efficiency as well as ability of particle recovery. Bovine serum albumin (BSA) model protein was encapsulated by poly(d,l-lactide-co-glycolide) (PLGA) using a multiple water-in-oil-in-water emulsion-solvent evaporation technique. The effect of three surfactants: polyvinyl alcohol, poloxamer, and polyvinyl pyrrolidone, used in the outer water phase, on the properties of particles was investigated. The emulsifier/PLGA mass ratio played an important role in the preparation procedure of the particles. This ratio was found to be approximately 1 for polyvinyl alcohol (PVA) if the aim was to formulate nanoparticles with narrow size distribution (<220 nm), high yield and good encapsulation efficiency (>90%). Although, a ratio of 2:1 was sufficient to produce submicron particles by poloxamer with high yield, more than 70% and 90% encapsulation efficiency required minimum 4 and 10 emulsifier/PLGA mass ratio, respectively. Five times more PVA and 10 times more poloxamer than the PLGA mass were necessary to obtain nanoparticles which were easy to redisperse after centrifugation. Microparticles released more BSA than nanoparticles prepared by PVA, however, the situation was reverse with poloxamer. Microparticles formulated by polyvinyl pyrrolidone (PVP) showed the fastest in vitro release.     

Preparation and characterization of submicron hybrid magnetic latex particles

Micrometer magnetic hybrid particles are of great interest in biomedical field, and various morphologies have been prepared via encapsulation processes. Regarding submicron, only few processes have been investigated and the most recent one leading to highly magnetic submicron magnetic hybrid particles is based on oil in water magnetic emulsion (MES) transformation. The encapsulation of magnetic iron oxide nanoparticles forming oil in water MES was investigated using different styrene/cross‐linker divinylbenzene volume ratio in the presence of potassium persulfate initiator. The encapsulation performed in this work is basically conducted by using well‐defined oil in water MES as a seed in radical emulsion polymerization. The chemical composition, morphology, iron oxide content, magnetic properties, electrokinetic properties, particle size, and size distribution of the prepared magnetic hybrid particles were examined using various techniques. The desired perfect magnetic core and polymer shell morphology were successfully obtained, and the final magnetic hybrid particles are superparamagnetic in nature and exhibit high iron oxide content (64 wt %). Copyright © 2015 John Wiley & Sons, Ltd.     

A Comparative Analysis of Silicon Phthalocyanine Photosensitizers for in vivo Photodynamic Therapy of RIF-1 Tumors in C3H Mice

Photofrin® photodynamic therapy (PDT) has recently received FDA approval for the palliative treatment of to-tally and partially obstructing esophageal malignancies. However, there is a need for new PDT photosensitizers because Photofrin has a number of undesirable features. The purpose of this study was to evaluate the efficacy of four amine-bearing silicon phthalocyanines—Pc4, Pc10, Pc12 and Pc18—as potential PDT photosensitizers. Equimolar concentrations of these Pc were found to be highly effective at causing the regression of RIF-1 tumors trans-planted to C3H/HeN mice. The amount of Pc4 necessary to cause an equivalent amount of tumor regression in this model system was substantially less than the amount of Photofrin. The cutaneous phototoxicity of the silicon Pc photosensitizer was assessed by the utilization of the murine ear-swelling model. When C3H mice were exposed to 167 J/cm² of polychromatic visible light from a UVB-filtered solar simulator, which emitted UV radiation and visible light above 320 nm, the Pc produced little, if any, cutaneous photosensitivity. These results indicate that Pc4, Pc10, Pc12 and Pc18 are at least as effective as Photofrin in PDT protocols, while at the same time addressing many of the drawbacks of Photofrin.     

Synthesis and characterization of a novel binuclear iron phthalocyanine/reduced graphene oxide nanocomposite for non-precious electrocatalyst for oxygen reduction

Binuclear iron phthalocyanine/reduced graphene oxide(bi-Fe Pc/RGO) nanocomposite with good electrocatalytic activity for ORR in alkaline medium was prepared in one step. High angle annular dark field image scanning transmission electron microscopy(HAADF-STEM) and energy dispersive X-ray spectroscopy element mapping results show bi-Fe Pc was uniformly distributed on RGO. An obvious cathodic peak located at about-0.23 V(vs. SCE) in CV and an onset potential of-0.004 V(vs. SCE) in LSV indicate the as-prepared bi-Fe Pc/RGO nanocomposite possesses high activity which is closed to Pt/C for ORR. The ORR on bi-Fe Pc/RGO nanocomposite follows four-electron transfer pathway in alkaline medium. Compared with Pt/C, there is only a slight decrease(about 0.02 V vs. SCE) for bi-Fe Pc/RGO nanocomposite when the methanol exists. The excellent activity and methanol tolerance in alkaline solutions proves that bi-Fe Pc/RGO nanocomposite could be considered as a promising cathode catalyst for alkaline fuel cells.     

The encapsulation of an amphiphile into polystyrene microspheres of narrow size distribution

ABSTRACT: Encapsulation of compounds into nano- or microsized organic particles of narrow size distribution is of increasing importance in fields of advanced imaging and diagnostic techniques and drug delivery systems. The main technology currently used for encapsulation of molecules within uniform template particles while retaining their size distribution is based on particle swelling methodology, involving penetration of emulsion droplets into the particles. The swelling method, however, is efficient for encapsulation only of hydrophobic compounds within hydrophobic template particles. In order to be encapsulated, the molecules must favor the hydrophobic phase of an organic/aqueous biphasic system, which is not easily achieved for molecules of amphiphilic character.The following work overcomes this difficulty by presenting a new method for encapsulation of amphiphilic molecules within uniform hydrophobic particles. We use hydrogen bonding of acid and base, combined with a pseudo salting out effect, for the entrapment of the amphiphile in the organic phase of a biphasic system. Following the entrapment in the organic phase, we demonstrated, using fluorescein and (antibiotic) tetracycline as model molecules, that the swelling method usually used only for hydrophobes can be expanded and applied to amphiphilic molecules.     

Encapsulation of inorganic particles via miniemulsion polymerization

The encapsulation of TiO₂ particles via miniemulsion polymerization is strongly dependent on the size and stability of the inorganic particles in the monomer medium in which they are initially dispersed. It was found from XPS and FT‐IR studies that both the hydrophilic and hydrophobic TiO₂ particles, which were studied, have hydroxyl groups present on their surfaces, which can strongly interact with the amine end‐groups of the polymeric stabilizer, OLOA370 (polybutene‐succinimide diethyl triamine). It was found from the dispersion and adsorption studies that the amount of OLOA370 retained on the TiO₂ particles is strongly dependent on the area exposed by the sonification that is applied to break up the aggregates in the dispersion process. The TiO₂ dispersions in styrene monomer were themselves dispersed as miniemulsion droplets and subsequently polymerized. It was concluded from the density gradient column (DGC) analysis of the latexes obtained from the encapsulation polymerizations, that the stability of the inorganic particles in the monomer, as well as their particle size, significantly influence the encapsulation efficiencies. The use of the hydrophilic titanium dioxide particles in combination with the stabilizer, OLOA370, resulted in a good dispersibility, dispersion stability, and small TiO₂ particle size. This lead to better encapsulation efficiencies compared to the hydrophobic particles. The poorer results obtained with the hydrophobic TiO₂ particles were attributed to their larger particle size, which resulted from the reduced adsorption of the OLOA370. Fewer hydroxyls and the presence of the trimethoxy octyl silane (TMOS) groups, which themselves are unable to provide sufficient steric stability, are proposed to explain these findings.     

Aggregation behavior of heteroleptic tris(phthalocyaninato) dysprosium complexes with different alkoxy chains in monolayer or multilayer solid films

Three heteroleptic tris(phathlocyaninato) dysprosium triple-decker complexes with different alkoxy groups at the peripheral positions of the medium phthalocyanine ligand (Pc)Dy[Pc(OCnH(2n+1))8]Dy(Pc) (n = 4, 8, 16) (I-III) {Pc = unsubstituted phthalocyaninate; Pc(OC4H9)8 = 2,3,9,10,16,17,23,24-octakis(butyloxy)phthalocyaninate; Pc(OC8H17)8 = 2,3,9,10,16,17,23,24-octakis(octyloxy)phthalocyaninate; Pc(OC16H33)8 = 2,3,9,10,16,17,23,24-octakis(hexadecyloxy)phthalocyaninate} have been synthesized, and their aggregate behaviors in monolayer and multilayer solid films have been comparatively studied. The pure compounds and their 1:4 mixtures with stearic acid (SA) have been found to form a stable monolayer at the air/water interface with a tilted edge-on orientation of (Pc)Dy[Pc(OCnH(2n+1))8]Dy(Pc) molecules. In the pure monolayers of the three triple-decker compounds, wirelike molecular aggregates were observed by high-resolution transmission electron microscopy (HRTEM). Adding SA has been found to prevent triple-decker compounds (Pc)Dy[Pc(OC4H9)8]Dy(Pc) (I) and (Pc)Dy[Pc(OC8H17)8]Dy(Pc) (II) from forming large aggregates, and small domains with a diameter of ca. 10 nm were observed in the mixed monolayers. HRTEM studies revealed that two crystalline phases with rectangular and hexagonal lattice structure are present in the small domains. However, both pi-A isotherms and HRTEM studies indicated that the mixed monolayer of compound (Pc)Dy[Pc(OC16H33)8]Dy(Pc) (III) with SA did not show a difference from the corresponding pure monolayer. The SA molecules were pressed into the cavity above the phthalocyanine ring formed by the eight long hexadecyloxy side chains of the medium macrocycle ligand in III. The multilayer LB films of all of these triple deckers fabricated by the vertical dipping method showed very good layered structure as revealed by the multiple-order diffraction peaks in low-angle X-ray diffraction (LAXRD) patterns.     

质子化和脱质子化对酞菁光谱的影响

系统地研究四异丙氧基酞菁的子化和脱质子化对吸收和发射光谱的影响，研究表明，三氟乙酸可对酞菁分子连续质子化，分别生成（Ｈ２Ｐｃ（Ｏ＾ｉＰｒ）４．Ｈ＾＋）＾和（Ｈ２Ｐｃ（Ｏ＾ｉＰｒ）４．２Ｈ＾＋）＾２＋，而硫酸可使酞菁形成（Ｈ２Ｐｃ（Ｏ＾ｉＰｒ）４．４Ｈ＾＋＾４＋此外，ＮａＯＨ／ＥｔＯＨ可使酞菁分子脱质子化生成（Ｐｃ（Ｏ＾ｉＰｒ）４）＾２－反应一步完成，表明分子中的两个吡咯－ＮＨ－同步酸解，质子化可使