Self-assembly of amphiphilic meso-aryl-substituted porphyrin derivatives in the presence of surfactants

2020 ◽  
Vol 24 (04) ◽  
pp. 505-514
Author(s):  
Margaret A. Gradova ◽  
Oleg V. Gradov ◽  
Kseniya A. Zhdanova ◽  
Natalya A. Bragina ◽  
Anton V. Lobanov

Surfactant-assisted self-assembly of porphyrin molecules in aqueous solutions sometimes leads to the formation of hybrid supramolecular structures with unusual photophysical properties resulting from the dipole–dipole interactions between the neighboring aromatic systems. The macrocycle orientation and interchromophore distance in such assemblies are determined by the dye–surfactant interactions, and hence, strongly depend on the molecular structure of both surfactant and porphyrin molecules. In this paper we studied the influence of the number and position of the peripheral alkyl chains of amphiphilic meso-aryl-substituted porphyrins on their aggregation behavior and intermolecular interactions with different surfactants in aqueous solutions. The studies revealed a crucial role of the local acidity on the micellar surface in the protolytic equilibrium of the porphyrin derivatives, as well as the influence of the macrocycle hydrophilic–lipophilic balance on its solubilization site within a micellar system. These findings enable prediction of the photophysical properties of amphiphilic porphyrin derivatives in the presence of different solubilizing agents and membrane-mimetic systems, and hence, selection the most suitable drug delivery systems for the novel amphiphilic porphyrin-based photosensitizers.

2019 ◽  
Vol 20 (18) ◽  
pp. 4604 ◽  
Author(s):  
Ihsan ◽  
Nargis ◽  
Koyama

A series of N-substituted poly(Gly–alter–Val) peptides were successfully synthesized for the systematic evaluation of the micellization behavior of alternating peptides. Three-component polymerization employing an aldehyde, a primary ammonium chloride, and potassium isocyanoacetate afforded four alternating peptides in excellent yields. We investigated the dependence of the hydrophilic–lipophilic balance of alternating peptides on the micellization behavior. All the aqueous solutions of alternating peptides exhibited upper critical solution temperature (UCST) behaviors, strongly indicating that the alternating binary pattern would mainly contribute to the UCST behaviors. The cloud points of alternating peptides shifted to higher temperatures as the side chains became more hydrophilic, which is opposite to the trend of typical surfactants. Such unusual micellization behaviors appeared to be dependent on the quasi-stable structure of single polymer chains formed in water.


2015 ◽  
Vol 19 (07) ◽  
pp. 845-851 ◽  
Author(s):  
Margaret A. Gradova ◽  
Vladimir V. Artemov ◽  
Anton V. Lobanov

Porphyrin-surfactant interactions in aqueous solutions are known to result in the selfassembly of various supramolecular structures, including pigment-surfactant complexes, J- and H-aggregates, and solubilized dye species. Detailed studies on the mechanisms of the intermolecular interactions governing the above self-assembly processes allow to predict the aggregation state and hence, the photophysical properties of the dye-surfactant assemblies in order to perform a direct synthesis of the desired porphyrin-based nanostructures at the appropriate experimental conditions. This paper describes a novel example of the surfactant-induced J-aggregate formation from the diprotonated hydrophobic tetraphenylporphyrin species in submicellar aqueous anionic surfactant solutions. The above assemblies are characterized by a rod-like morphology and possess supramolecular chirality according to the CD measurements.


2015 ◽  
Vol 8 (3) ◽  
pp. 244-251 ◽  
Author(s):  
Margaret A. Gradova ◽  
Vladimir N. Kuryakov ◽  
Anton V. Lobanov

2019 ◽  
Author(s):  
F Foerster ◽  
K Mönkemüller ◽  
PR Galle ◽  
H Neumann

Author(s):  
Vike Martina Plock

This chapter analyzes the role of fashion as a discursive force in Rosamond Lehmann’s 1932 coming-of-age novel Invitation to the Waltz. Reading the novel alongside such fashion magazines as Vogue, it demonstrates Lehmann’s awareness that 1920s fashion, in spite of its carefully stylized public image as harbinger of originality, emphasized the importance of following preconceived (dress) patterns in the successful construction of modern feminine types. Invitation to the Waltz, it argues, opposes the production of patterned types and celebrates difference and disobedience in its stead. At the same time, the novel’s formal appearance is nonetheless dependent on the very same tenets it criticizes. On closer scrutiny, it is seen to reveal its resemblance to Virginia Woolf’s To the Lighthouse (1927). A tension between imitation and originality determines sartorial fashion choices. This chapter shows that female authorship in the inter-war period was subjected to the same market forces that controlled and sustained the organization of the fashion industry.


2020 ◽  
Vol 11 (SPL1) ◽  
pp. 977-982
Author(s):  
Mohamed J. Saadh ◽  
Bashar Haj Rashid M ◽  
Roa’a Matar ◽  
Sajeda Riyad Aldibs ◽  
Hala Sbaih ◽  
...  

SARS-COV2 virus causes Coronavirus disease (COVID-19) and represents the causative agent of a potentially fatal disease that is of great global public health concern. The novel coronavirus (2019) was discovered in 2019 in Wuhan, the market of the wet animal, China with viral pneumonia cases and is life-threatening. Today, WHO announces COVID-19 outbreak as a pandemic. COVID-19 is likely to be zoonotic. It is transmitted from bats as intermediary animals to human. Also, the virus is transmitted from human to human who is in close contact with others. The computerized tomographic chest scan is usually abnormal even in those with no symptoms or mild disease. Treatment is nearly supportive; the role of antiviral agents is yet to be established. The SARS-COV2 virus spreads faster than its two ancestors, the SARS-CoV and Middle East respiratory syndrome coronavirus (MERS-CoV), but has lower fatality. In this article, we aimed to summarize the transmission, symptoms, pathogenesis, diagnosis, treatment, and vaccine to control the spread of this fatal disease.


2020 ◽  
Vol 2 (3) ◽  
pp. 19-23
Author(s):  
Shakhlo Botirova ◽  
Keyword(s):  

In this article , in the novel “Rebellion and obedience” by Ulugbek Hamdam, the author analyzes the artistic psychological description of a person on the path of development in the center of an integral complex metaphorical system of being. The novel “Rebellion and obedience” is based onthe method of metaphorization of reality. In it, a personexperiences vertigo about who he is and what powerful being he possesses. The reason for this is a riot. After much agony, he obeys. Allegedly thus proves its existence. Finds answers to certain riddles


Author(s):  
Larisa Botnari

Although very famous, some key moments of the novel In Search of Lost Time, such as those of the madeleine or the uneven pavement, often remain enigmatic for the reader. Our article attempts to formulate a possible philosophical interpretation of the narrator's experiences during these scenes, through a confrontation of the Proustian text with the ideas found in the System of Transcendental Idealism (1800) of the German philosopher F. W. J. Schelling. We thus try to highlight the essential role of the self in Marcel Proust's aesthetic thinking, by showing that the mysterious happiness felt by the narrator, and from which the project of creating a work of art is ultimately born, is similar to the experiences of pure self-consciousness evoked and analyzed by Schellingian philosophy of art.


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