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1

Synthesis of Silica Microspheres Containing Iron Oxide Nanoparticles for Removal of Organic Pollutant by Adsorption and Photocatalytic Decomposition

Cho Young-Sang, Sung Sohyeon

Archives of Metallurgy and Materials

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2021

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Vol. 66, iss. 3

771--776

EN

Iron oxide nanoparticles were incorporated to form composite microspheres of SiO2 and Fe2O3 for magnetic separation of the particles after adsorption or photochemical decomposition. Economic material, sodium silicate, was purified by ion exchange to prepare aqueous silicic acid solution, followed by mixing with iron oxide nanoparticles. Resulting aqueous dispersion was emulsified, and composite microspheres of SiO2 and Fe2O3 was formed from the emulsion droplets as micro-reactors during heating. Removal of methylene blue using the composite microspheres was performed by batch adsorption process. Synthesis of composite microspheres of silica containing Fe2O3 and TiO2 nanoparticles was also possible, the particles could be separated using magnets efficiently after removal of organic dye.

2

Self-ordered cellulose nanocrystals and microscopic investigations

Castro-Guerrero C. F., Morales-Cepeda A. B., Díaz-Guillén M. R., Delgado-Arroyo F., López-González F. A.

Materials Science Poland

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2020

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Vol. 38, No. 4

613--618

EN

Cellulose nanocrystals were extracted from cotton. The cellulose nanocrystals made a self-assembly structure when dried under slow conditions, as it was revealed by the characterization made to the material. The AFM images of the nanocrystals showed that they had a changing local orientation, pointing in a preferred direction that underwent a periodic change. This periodic change resembles the orientation of a chiral nematic phase. The TEM images showed that the nanocrystals had a rod-like appearance with average length size of 98.5 nm and a diameter of 4.7 nm. The TEM characterization showed the nanocrystals with more details than AFM. In this paper, the self-assembling of CNC was observed by AFM, and further investigations were done by TEM, deconvoluting the process of CNC nanorods aggregation.

3

Dual Self-Assembly in Strongly Asymmetric A-B-A Triblock Copolymer Melts Studied by Self-Consistent Field Theory and Monte Carlo Simulations

Dzięcielski L., Wołoszczuk S., Banaszak M.

Computational Methods in Science and Technology

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2018

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Vol. 24, No. 4

227--234

EN

Using the Self-Consistent Field Theory (SCFT) we study the dual self-assembly of ABA triblock copolymers melts and compare the numerical results with those obtained by the lattice Monte Carlo simulations. While the results are qualitatively similar for both methods, the simulation times are significantly shorter for the SCFT calculations than those for the corresponding Monte Carlo simulations

4

Gra przestrzenna w kształtowaniu struktury mieszkaniowej

Broma T.

Architectus

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2017

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Nr 4 (52)

89--98

PL

W artykule zaprezentowano grę przestrzenną o nazwie Parcelacja kubaturowa, która została opracowana na potrzeby projektu dyplomowego S’lowtecture: struktura mieszkaniowa. Gra jest algorytmem, który pozwala na generowanie wariantowych układów jednostek mieszkaniowych oraz ich osadzenie w bloku urbanistycznym. Jej zasady samoorganizują przestrzennie strukturę, gwarantują dostęp jednostek mieszkaniowych do niezbędnej infrastruktury, a mieszkańcom zapewniają możliwość indywidualizacji domostwa i jego elastycznego dopasowania do aktualnych potrzeb. Parcelacja kubaturowa jest próbą stworzenia algorytmu zarządzającego strukturą mieszkaniową, który ma na celu eliminację blokad, konfliktów i innych niekorzystnych zjawisk przestrzennych. Jednocześnie jego zadaniem jest pozostawienie mieszkańcom jak największej niezależności w tworzeniu jednostek mieszkaniowych. Artykuł stanowi szczegółowy opis zasad Parcelacji kubaturowej oraz symulacji przeprowadzonej na fragmencie struktury mieszkaniowej.

EN

The article presents a spatial game called Cubic parcellation, which was created for the diploma project S’lowtecture: housing structure. The game is an algorithm that allows generating variant housing structures plans and their placement in the urban block. Its rules spatially self-assemble the structure, guarantee housing units access to the necessary infrastructure and residents the opportunity to individualize their houses and its flexibility to adapt to current needs. Cubic parcellation is an attempt to create an algorithm that will be managing the housing structure, which aims to eliminate blockages, conflicts and other negative spatial phenomena. At the same time its task is to leave to the inhabitants as much independence as it is possible while creating housing units. The article is a detailed description of the Cubic parcellation rules and the simulation carried out on a piece of a housing structure.

5

Computational insights into the self-assembly of phenylalanine-based molecules

German H. W., Bhavaraju M., Uyaver S., Hansmann U. H. E.

TASK Quarterly : scientific bulletin of Academic Computer Centre in Gdansk

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2014

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Vol. 18, No 4

357--363

EN

In a recent paper “Self-Assembly of Phenylalanine-Based Molecules”, we h ave studied the formation and stability of phenylalanine and diphenylalani ne constructs. In the case of diphenylalanine we observe nanotubes, however, phenylalanin e molecules aggregate in layers of four, not six, molecules. In the preset paper, we extend this previous work and compare the energetics of all experimentally observed structures, s imulated structures, and designed structures, by way of single point Density Functional The ory ( DFT ) calculations. We take a detailed look at water content, pore size and dipole moments inside ou r phenylalaninecontaining tubes and analyze stabilizing factors in the nanostructures.

6

Irregular shaping of polystyrene nanosphere array by plasma etching

Luo H., Liu T., Ma J., Wang W., Li H., Wang P., Bai J., Jing G.

Materials Science Poland

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2013

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Vol. 31, No. 3

331--337

EN

The morphology of nanospheres is crucial for designing the nanofabrication in the nanosphere lithography. Here, by plasma etching, the controllable tailoring of the nanosphere is realized and its morphology dependence on the initial shape, microscopic roughness, and the etching conditions is investigated quantitatively. The results show that the shape evolution strongly depends on the etching gas, power, and process duration. Particularly, the aspect ratio (diameter/height) significantly increases with violent etching, turning the spherical shape into tiny ellipsoidal nanoparticles. The findings are practical to the protocol of non-uniform etching of nanoobjects and provide the useful design tool for the device fabrication at nanoscale.

7

Self-assembling micelles obtained from PLLA/PEG and PDLA/PEG block copolymers in aqueous solutions

Wu X, Li S.

Engineering of Biomaterials

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2012

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Vol. 15, no. 113

6--8

EN

A series ofpolylactide-poly(ethylene glycol) (PLA- PEG) block copolymers were synthesized by ring-opening polymerization of L- or D-lactide in the presence of mono- or dihydroxyl PEG, using nontoxic zinc lactate as catalyst. Micelles were then prepared by direct dissolution of the obtained copolymers in aqueous medium without heating or using any organic solvents. Aqueous gel permeation chromatography and dynamic light scattering measurements were carried out to characterize the resulting micelles. Generally, mixed micelles containing both PLLA/PEG and PDLA/PEG copolymers appear lager and more compact compared to single ones. However, the size of mixed micelles is smaller than that of single ones which exhibit an anisotropic structure since stereocomplexation disfavors the formation of anisotropic micelles. The copolymer parameters such as structures, molar mass and PEG fraction strongly influence the formation of anisotropic micelles, and thus lead to various micellar sizes.

8

Architektury supramolekularne jako wynik samoorganizacji w kompleksach jonów metali d- i f- elektronowych

Patroniak V.

Wiadomości Chemiczne

|

2010

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[Z] 64, 3-4

285-318

EN

The use of transition metal complexes of bridging multidentate ligands to construct predictable, self-assembled small inorganic systems and multi-dimensional infinite networks is an area of chemistry which has received ever-increasing attention over the recent years. Self-organization occurs usually from a mixture of components (organic ligands, salt crystals, and sometimes solvent molecules). The products exhibit a notable thermodynamic and kinetic stability and their components should contain all the information necessary for a correct assembly to occur [1–6]. Self-assembly has recently been studied in many types of organic and inorganic systems. This latter approach has proven particularly successful for the generation of a wide spectrum of architectural topologies such as for example, helicates [7–11], rotaxanes [12, 13], clusters [14–16], ladders [17–19], cages [20–22], grids [23–25] and molecular wheels [26–28], etc., based on ligand design and an application of suitable coordination geometries for the assembling system. The structure of supramolecular complexes depends strongly on the ligand substituent, the ligand conformation, the metal ion, the counterion, the solvent, and the reaction conditions [29–37]. Such compounds may exhibit novel physical and chemical properties with a potential use in supramolecular engineering, nanotechnology, biomedical inorganic chemistry, biological catalysis, and in the area of sensors [38–46]. The review has been prepared on the results of my own studies in the field [47–59] and focused on structural diversity and characterization of supramolecular complexes. The architectures of these compounds generated by self-assembly of polypirydyl ligands with d-and f-metal ions are fascinating and attractive because of their unusual properties and prospective implementation in many application [60–74].

9

Self-assembly: mastering photonic processes at nanoscale

Fiorini C., Charra F.

Opto-Electronics Review

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2010

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Vol. 18, No. 4

376-383

EN

Supramolecular ordering happens as an important parameter for the control of light emission processes. In this review paper, we discuss several examples of application of self-assembly to the realization of nano-structures designed in view of mastering specific photonic processes. This comprises the formation of highly localized plasmon modes in self-organized 2D assemblies of metal nanoparticles, the immobilization of dyes inside highly homogeneous 2D alveolar self-assembled molecular matrices and molecular 3D building blocks designed to combine in-plane periodicity and off-plane π-conjugated protrusions. Finally, we will discuss 3D self-assembly in solution with the example of fluorescent labelling of DNA.

10

Self-assembled Synthesis, Characterization and Antimicrobial Activity of Dinuclear Lanthanide Salicylaldimine Complexes Derived from Cadaverine

Radecka-Paryzek W., Pospieszna-Markiewicz I., Kędzia B.

Polish Journal of Chemistry

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2009

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Vol. 83, nr 10

1693-1700

EN

The new bimetallic lanthanide salicylaldimine complexes of the formula Ln2(H2L)3(NO3)6×2H2O, where Ln = La3+, Eu3+ or Gd3+ and H2L = N,N'- bis(salicyl -idene)-1,5-pentanediamine, are formed in a self-assembly process in volving the lanthanide template-induced one-pot Schiff base condensation reaction between salicylaldehyde and biogenic diamine cadaverine (1,5-pentanediamine). The complexes were characterized by spectroscopic methods (IR, 1H NMR, ESI-MS, UV-Vis, luminescence), and thermogravimetric and elemental analysis. The salicylaldimine with a potentially tetradentate N2O2 set of donor atms displays a rare coordination pattern acting as a neutral ligand using exclusively oxygens as donor atoms with out in volving the nitrogen atoms in the coordination. The europium(III) complex was tested for antimicrobial activity against Staph y lo coc cus aureus in a minimum inhibitory concentration (MIC) experiment.

11

Controllable synthesis of ZnO nanostructures by a simple solution route

Wang J., He S., Zhang S., Li Z., Yang P., Jing X., Zhang M., Jiang Z.

Materials Science Poland

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2009

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Vol. 27, No. 2

477--484

EN

Flower-shaped ZnO nanostructures, composed of ZnO nanorods, and sphere-shaped ZnO nanoclusters, composed of ZnO nanosheets, were synthesized by reacting zinc acetate dehydrate with sodium hydroxide and polyethylene glycol-20000 (PEG-20000) at 180 °C for 4 h in solution. The thickness of individual nanosheets is about 40-60 nm. The nanorods are of hexagonal shape with sharp tips, and have basic diameters of ca. 450-550 nm. The ZnO nanostructures were characterized by scanning electron microscropy, transmission electron microscopy, X-ray diffraction, Fourier transform infrared, and Raman scattering measurements. The results demonstrated that the synthesized products are single crystalline with wurtzite hexagonal phase, the sphere-shaped ZnO grew in the [100] direction and the flower-shaped ZnO grew in the [001] direction.

12

Self-Assembled Grid-Type Complexes of Manganese(II), Iron(II), Cobalt(II) and Zinc(II)

Ciesielski A., Wałęsa M., Patroniak V.

Polish Journal of Chemistry

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2008

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Vol. 82, nr 6

1231-1236

EN

The self-assembly of the heterotopic ligand L, containing two N-tridentate binding units, with manganese(II), iron(II), cobalt(II) and zinc(II) carried out to the formation of supramolecular architectures containing four ions in octahedral coordination sites. The [2x2] grid-type structures have been characterized by the spectroscopic data and microanalyses.

13

Heterobimetallic Zinc and Lanthanide Salicylaldimine Complexes Formed in Self-Assembly Process

Kaczmarek M. T., Radecka-Paryzek W.

Polish Journal of Chemistry

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2008

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Vol. 82, nr 6

1213-1218

EN

The new 3d-4f heterobimetallic salicylaldimine complexes of the formulas ZnLaL2(NO3)5×5H2O, ZnGdL2Cl5×6H2O and ZnGdL3(NO3)5×5H2O, where L is N,N'- bis(salicylidene)-1,3-phenylenediamine, were synthesized by the template-in duced Schiff base condensation reaction between salicylaldehyde and 1,3- phenylene diamine in the presence of appropriate metal ions acting as templates. The complexes were characterized by spectroscopic methods (IR, 1H NMR, ESI-MS) and elemental analysis.

14

Synthesis and 1H-NMR Characterization of the Self-Assembly Based on Melamine – 5,5-Diethylbarbituric Acid

Pokrop A., Lipkowski P., Jurczak J.

Polish Journal of Chemistry

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2007

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Vol. 81, nr 5-6

893-901

EN

The characterization of carbonyl–metal and maleimidato–metal bonding has been performed using the topological analysis of electron distribution function estimated for molecules of ( 5-C5H5)M(CO)3( 1-N-maleimidato) (M = W, Mo) and ( 5-C5H5)Fe(CO)2( 1-N-maleimidato). The Atoms in Molecules (AIM) approach has been applied for characterization of and -components of the metal–ligand bonds. The -electron communication between trans-placed ligands is present in Wand Mo derivatives. The ellipticity parameter is suggested to be a useful and highly sensitive parameter in the analysis of the metal–ligand bonding

15

Multiset-Based Self-Assembly of Graphs

Bernardini F., Brijder R., Rozenberg G., Zandron C.

Fundamenta Informaticae

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2007

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Vol. 75, nr 1-4

49-75

EN

We present a model for self-assembly of graphs based on multisets and the formalism of membrane systems. The model deals with aggregates of cells which are defined as undirected graphs where a multiset over a fixed alphabet is assigned to each vertex. The evolution of these aggregates is determined by an application of multiset-based aggregation rules to enlarge the current structure as well as an application of membrane-systems-based communication rules to enable cells to exchange objects alongside the edges of the graph. We compare the generative power of self-assembly membrane systems with and without communication rules, and we characterise properties of the sets of graphs generated by these systems. We also introduce two notions of stability for self-assembly processes that capture the idea of having produced a stable structure. Finally, we investigate self-assembly membrane systems where the alphabet is a singleton.

16

X-ray microdiffraction on flow-controlled biomolecular assemblies

Evans H.M., Dootz R., Köster S., Pfohl T.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2007

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Vol. 55, nr 2

217-227

EN

The study of liquid crystalline assemblies, with an emphasis on biological phenomena, is now accessible using newly developed microdevices integrated with X-ray analysis capability. Many biological systems can be described in terms of gradients, mixing, and confinement, all of which can be mimicked with the use of appropriate microfluidic designs. The use of hydro-dynamic focusing creates well-defined mixing conditions that vary depending on parameters such as device geometry, and can be quantified with finite element modelling. We describe experiments in which geometry and strain rate induce finite changes in liquid crystalline orientation. We also demonstrate the online supramolecular assembly of lipoplexes. The measurement of lipoplex orientation as a function of flow velocity allows us to record a relaxation process of the lipoplexes, as evidenced by a remarkable 4-fold azimuthal symmetry. All of these processes ale accessible due to the intentional integration of design elements in the microdevices.

17

Efficient Synthesis of Macrocyclic Dilactam Crown Ethers by Fast Addition Method

Rahimzadeh M., Eshghi H., Rostami F., Faghihi Z.

Polish Journal of Chemistry

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2005

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Vol. 79 / nr 1

73-81

EN

A simple and convenient method for preparing macrocyclic dilactam crown ethers containing N2O5, N3O3, N3O4, N3O5 and N2O10 donor atoms with 18-32 membered rings was developed. These compounds were obtained in the macrocyclization step under vigorous stirring conditions as well as fast addition of reactants. This step does not require external cyclization factors such as high dilution approach, template effect or nitrogen protection and provides the expected dilactams in high yields, ranging from 65-95%. The course of the reaction is assumed to depend on the occurrence of self assembly phenomena which are stimulated by a logic concentration in a selected solvent and the yields are improved by application of high speed stirring and fast addition of reactants.

18

Tworzenie i rozdział kompleksów białek surowicy z barwnikami supramolekularnymi w elektroforezie dwukierunkowej - próba opracowania komputerowej techniki analizy obrazu rozdziałowego

Rybarska J., Spólnik P., Drozd A., Konieczny L., Piekarska B., Stopa B., Zemanek G., Król M., Roterman-Konieczna I.

Bio-Algorithms and Med-Systems

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2005

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Vol. 1, no. 1/2

133--138

PL

Praca przedstawia badania eksperymentalne mające na celu wykrycie zmian w składzie białkowym zmienionej chorobowo surowicy ludzkiej. Dla wykrycia zmian opracowano dwukierunkową technikę elektroforetyczną umożliwiającą tworzenie kompleksów przez barwniki o charakterze ciekłokrystalicznym z białkami. Taśmowe micele barwnika mogą przylegać do szkieletu łańcucha polipeptydowego w obszarach jego ekspozycji, tworząc kompleksy. Warunki elektroforetyczne pozwalają na usunięcie nadmiaru oraz puli słabo związanego z białkami barwnika. Tworzenie kompleksów w elektroforezie pozwala na ujawnienie kompleksów białek z barwnikami, które wędrują szybciej niż białka niezaangażowane w wiązanie barwnika. Nieprawidłowe oraz przejściowo zdestabilizowane natywne białka mogą być podatne na penetrację i wiązanie dużych supramolekularnych ligandów. Do grupy białek wiążących należą białka szpiczakowe oraz serpiny, haptoglobiny i immunoglobuliny, ulegające przegrupowaniu podczas tworzenia kompleksów ze swoimi fizjologicznymi ligandami. Elektroforeza surowicy prowadzona jest dwuetapowo w prostopadłych względem siebie kierunkach. Pierwszy rozdział jest standardowy. Drugi modyfikowany jest przez kontakt i ewentualną interakcję rozdzielonych uprzednio białek z dodanym barwnikiem. Szybciej wędrujący barwnik, którego punkt nałożenia znajduje się poniżej białek, napotyka w trakcie wędrówki i wyprzedza białko. Białka zdolne do tworzenia kompleksów zabarwiają się w takich warunkach oraz wędrują szybciej od swoich nieskompleksowanych z barwnikiem odpowiedników. Po redukcji barwników dwutioninem sodowym z następowym zabarwieniem błękitem bromofenolowym, można uzyskać kompletny proteinogram rozdzielanej surowicy. Próby opracowania pół-automatycznej i automatycznej analizy uzyskiwanego w elektroforezie rozdziału plam zostały ostatnio podjęte.

EN

Two-dimensional agarose electrophoresis was used to create suitable conditions for the formation of protein complexes with supramolecular dyes. Ribbon-shaped dye molecule ligands adhere during complexation to the polypeptide backbone of β-conformation within protein clefts. The electrophoresis helps to remove the dye excess and the dye weakly attached to protein molecules. It simultaneously allows for the exposure of protein-dye complexes migrating faster than proteins not engaged in complexation. Abnormal and transiently destabilized native proteins become susceptible to penetration and binding by large supramolecular dye ligands. This includes many myeloma proteins as well as serpins, haptoglobins and immunoglobulins engaged in their natural complexes. Electrophoresis of serum proteins is conducted in two steps: the first is a standard electrophoresis while the second (perpen-dicular run) is modified by the contact and interaction of separated serum proteins (during the first step) with the added dye. The fast migrating dye, for which the starting position is retreated versus to that of proteins, meets and overruns the proteins. The proteins which are susceptible to dye penetration and binding become stained and their migration is accelerated. The complete proteinogram including the binding and non-binding dye proteins may be revealed by standard staining with bromophenol blue after removal of the supramolecular dye. An attempt for semi-automatic or automatic analysis of spots distributed in electrophoresis has been undertaken.

19

Synthesis and Structural Characterization of Self-Assembly Products Containing [Fe(CN)6]4- Building Blocks with Cationic {R3Sn}+ Fragments in the Absence or Presence of a Bidentate Uncharged LIgand {2L}

Ibrahim M., Morgan A., Mecky A., Etaiw S.

Polish Journal of Chemistry

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2004

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Vol. 78 / nr 2

173-185

EN

Spontaneous self-assembly of [Fe(CN)6]4- andR3Sn+ ions (R = Me, n-Bu or Ph) in the absence or presence of uncharged bidentate ligands (such as dioxane (diox), methylpyrazine (Mepyz), or 4,4_-bipyridine (bpy)) affords white precipitates. The products with the general composition [(R3Sn)4Fe(CN)6_2H2O_2L]; 2L = diox, Mepyz or bpy, have been obtained as host-guest polymeric architecture. The new compounds have been compared with their hydrated systems [(Me3Sn)4Fe(CN)6_xH2O]; x = 2 or 4 and with the water-free [(Me3Sn)4Fe(CN)6]. Results of extensive spectroscopic investigations (IR studies and X-ray powder diffractometry) suggest that the architecture of the novel host-guest systems involve three-dimensional networks, notably different from those of their parent system (containing fourH2Omolecules). These compounds show no ion-exchange activity towards NH4 + cations and are affected by moderate temperature. Also, these 3D-host-guest polymeric systems exhibit a high sensitivity to pH of the media.