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Porphyrins are functional elements of important biomolecules, whose assemblies play a central role in fundamental processes such as electron transfer, oxygen transport, enzymatic catalysis, and light harvesting. Here we report an approach to formation of porphyrin supermolecules, a particular type of nanoparticles with unusually strong noncovalent intermolecular interactions. Key differences between the supermolecules and noncovalent nanostructures described earlier are as follows. (1) Supermolecules consist of molecules of the same type without side groups promoting the self-assembly and without any spacers; no surfactant or catalyst to assist the process is needed. (2) They exhibit unusual photophysical properties and remain stable even in organic solvents. Their formation occurs under specially selected conditions at the air-water interface at room temperature. Following this route, we have formed supermolecules of magnesium porphine, a functional element of chlorophyll. The properties of these supermolecules are markedly different from those of the constituent molecules. For example, in contrast to the pink color of the monomer solution, solutions of supermolecules are transparent for visible light and absorb in the ultraviolet and near-infrared regions. We also present atomic force microscopy visualization of the porphyrin two-dimensional nanoaggregates forming at the air-water interface that were predicted in our previous works. This approach offers a guideline for the discovery of new supermolecules, including complex biological ones, and the formation of supermolecular materials with novel properties.

Nanoarchitectures with promising properties have now been formed from many important biomolecules. However, the preparation of nanoparticles of vitamin B 12 and its derivatives remains an ongoing research challenge. This paper describes the formation of supermolecular nanoentities (SMEs) of vitamin B 12 derivatives, unique nanoparticles with strong noncovalent intermolecular interactions, emerging properties, and activity. These were created by a nanoarchitectonic approach using directed assembly of layers at the air−water interface as a link in the chain of evolution of the parent molecules under specially created conditions. Such layers can be represented as a nanocosm, where, at a critical density, the assemblies act as nanoreactors in which the transformation of the original material occurs. The discovered SMEs not only replicate the functioning of vitamin B 12 assemblies with proteins in living organisms and act as vitamin B 12 -depended enzymes but also demonstrate important advantages over vitamin B 12 . They are more efficient in oxygen reduction/evolution reactions and in transformation into other forms. These SMEs, in performing advanced tasks, are an alternative to widely used materials based on noble metals for catalysis, medicine, and environment protection. Our findings open new perspectives both for the fabrication of novel SMEs of biomolecules and for a better understanding of the evolution of biomolecules in nature.

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The aggregation behavior of unsubstituted magnesium porphyrazine (MgPz) was studied in layers at the water–air interface and in Langmuir–Schaefer films. Regions of existence and characteristics of the structure and properties of stable nanostructured monolayers of MgPz were determined with the method of quantitative analysis of compression isotherms of floating layers in a wide range of initial surface coverage degrees (ISCD). MgPz on the water surface forms monolayers of three types: a face-on type and two edge-on types that differ in the structure. The specific feature of the monolayers of the second type is the independence of the structure of two-dimensional MgPz nanoparticles formed on water on the ISCD. A mathematical model and a state diagram of the monolayer were constructed and a passport of MgPz monolayers was compiled. For the first time, the state diagram contains boundary isotherms based on data obtained from the model. Langmuir–Schaefer films of MgPz formed from layers of various types were prepared and studied by UV-vis absorption spectroscopy.

An experimental and theoretical study of 5,10,15-triphenylcorrole (H 3 [(ms-Ph) 3 Cor]) nano-structured floating layers (M-layers) [(ms-Ph) 3 Cor] на твердых подложках и изучены их спек-тральные характеристики.Ключевые слова: Плавающие монослои, 2D наноструктуры, М-наноагрегаты, модель М-монослоя, ЛШ-пленки, коррол.

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