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In photodynamic therapy (PDT), the low absorptivity of photosensitizers in an aqueous environment reduces singlet oxygen generation efficiency and thereby decreases photosensitizing efficacy in biological conditions. To circumvent this problem, we designed a phthalocyanine-poly-L-glutamic acid conjugate ( 1-PG ) made from a new phthalocyanine ( Pc 1 ) monofunctionalized to allow adequate conjugation to PGA. The resulting 1-PG conjugate retained high absorptivity in the near-infrared (NIR) region at its λ max 675 nm in an aqueous environment. The 1-PG conjugate demonstrated good singlet oxygen generation efficiency, increased uptake by 4 T1 breast cancer cells via clathrin-mediated endocytosis, and enhanced photocytotoxic efficacy. The conjugate also displayed a high light–dark toxicity ratio, approximately 1.5-fold greater than zinc phthalocyanine at higher concentration (10 μM), an important feature for the reduction of dark toxicity and unwanted side effects. These results suggest that the 1-PG conjugate could be a useful alternative for deep tissue treatment with enhanced anti-cancer (PDT) efficacy. [ABSTRACT FROM AUTHOR]

Abstract: In nature, interfacial molecular recognition and chirality are of fundamental significance for the construction of biological assemblies. Lipid monolayers at liquid interface can be used as biomimetic models for studying molecular interactions in such assemblies. In this article, we will focus on the use of Langmuir monolayers for studying self-organization and insertion properties of several neoglycolipids. Two types of glycolipids have been considered, one in the context of the analysis of glycoconjugates of biological relevance, and one dealing with the ability of some glycoprobes to insert into a monolayer in relation with their efficiency for serving as membrane imaging systems. [Copyright &y& Elsevier]

Abstract: A series of asymmetrically substituted phthalocyanines conjugated to four different carbohydrate units has been designed to be used as photosensitisers for potential selective recognition by targeted cells. [Copyright &y& Elsevier]

Abstract: A complete set of platinum(II) solketal substituted phthalocyanines has been synthesized and characterized. To evaluate their potential as Type II photosensitizers for photodynamic therapy, comparative studies of their photophysical and photochemical properties with analogous zinc(II) series have been achieved: electronic absorption, fluorescence quantum yields, lifetimes, and fluorescence quenching by benzoquinone, as well as singlet oxygen generation and photodegradation. It appears that platinum(II) phthalocyanines are worth being used as Type II photosensitizers, as they exhibit good singlet oxygen generation and appropriate photodegradation. [Copyright &y& Elsevier]

Abstract: Palladium-catalyzed copper-free Sonogashira cross-coupling reactions were performed on a protected and unprotected monoiodotriglycerol substituted Zn(II) phthalocyanine with various alkynes in organic and aqueous medium. From the silyl protected alkyne derivative, a protected homo coupled dimeric product was also prepared using Glaser coupling. All products were purified by reverse phase HPLC and the assigned structures were confirmed by mass and UV–vis spectroscopy. [Copyright &y& Elsevier]

A fluorinated phthalocyanine and its non-fluorinated analogue were selected to evaluate the potential enhancement of fluorination on photophysical, photochemical and redox properties as well as on biological activity in cellular and animal models. Due to the pharmacological relevance, the affinity of these phthalocyanines towards biological membranes (logP ow ) as well as their primary interaction with human serum albumin (HSA) or low-density lipoprotein (LDL) were determined. Water-dispersible drug formulation of phthalocyanines via Pluronic ® -based triblock copolymer micelles was prepared to avoid self-aggregation effects and to improve their delivery. The obtained results demonstrate that phthalocyanines incorporation into tunable-polymeric micelles significantly enhanced their cellular uptake and their photocytotoxicity. The improved biodistribution and photodynamic efficacy of the phthalocyanines-triblock copolymer conjugates was also confirmed in vivo in CT26 bearing BALB/c mice. PDT with both compounds led to tumor growth inhibition in all treated animals. Fluorinated phthalocyanine 2 turned out to be the most effective anticancer agent as the tumors of 20% of mice treated regressed completely and did not appear for over one year after treatment. [ABSTRACT FROM AUTHOR]

A cyclotriphosphazene substituted with six 3,5-bis(trifluoromethyl) benzyloxy units was designed as a novel 19 F MRI contrast agent. The resulting molecule has 36 magnetically equivalent fluorine atoms and exhibited suitable MRI properties with high imaging sensitivity, confirming the proof-of-concept as a convenient scaffold for the production of new 19 F MRI contrasts agents. [ABSTRACT FROM AUTHOR]

Abstract: A Zn(II) phthalocyanine substituted with eight hydroxylated sulfanyl moieties in non-peripheral positions was designed to exhibit properties desired for photodynamic therapy: hydrophilicity, isomeric purity and near-infrared absorption in addition to high singlet oxygen generation. Photophysical and photochemical studies proved to be promising. [Copyright &y& Elsevier]

A monoazido Zn phthalocyanine has been grafted onto three different alkynyl-functionalized peptoid helices using copper-catalyzed azide–alkyne cycloaddition, demonstrating the feasibility of such conjugates. Their photoproperties have been examined relatively to the spatial geometry induced by the peptoid helix. [Display omitted] • Peptoid chains with one and two alkynyl moieties on different residues have been prepared. • A monoazido Zn phthalocyanine has been grafted using copper-catalyzed azide–alkyne cycloaddition. • The absorption and fluorescence of these conjugates have been recorded. [ABSTRACT FROM AUTHOR]