Publications by authors named "Akhmadeev B"

The present work explores the specificity of supramolecular assemblies comprising dialkylaminostyrylhetarene dye molecules incorporated into phosphatidylcholine (PC) or phosphatidylserine (PS) aggregates. In PS-based assemblies, the dyes demonstrate a concentration-dependent fluorescent response, distinguishing anionic proteins such as bovine serum albumin (BSA) and pepsin from lysozyme (LYZ) in aqueous solutions. Conversely, no significant response is observed when the dyes are incorporated into the well-organized bilayers of neutral PC.

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To date, researchers in chase of economic cost-efficiency are faced with the problem of developing effective catalysts for water splitting without the use of platinoids. Herein, catalytic properties of hexanuclear rhenium cluster complexes are investigated in application to the hydrogen evolution reaction (HER). A paste composite electrode containing the cluster complexes was obtained, producing a current density of 10 mA cm at an extraordinarily low overpotential of 90 mV (RHE).

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Development of nanoparticles (NPs) serving as contrast enhancing agents in MRI requires a combination of high contrasting effect with the biosafety and hemocompatibility. This work demonstrates that bovine serum albumin (BSA) molecules bound to paramagnetic Mn ions are promising building blocks of such NPs. The desolvation-induced denaturation of BSA bound with Mn ions followed by the glutaraldehyde-facilitated cross-linking provides the uniform in size 102.

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The present work demonstrates the structure variation of hexarhenium anionic cluster units [{ReS}(CN)(OH)] (n = 0, 2, 4) as the strategy to develop Mn-containing nanoparticles (NPs) exhibiting pH-dependent leaching. The dicyanotetrahydroxo complex [{ReS}(CN)(OH)] is the optimal for the synthesis of the Mn-based NPs with a lamellar shape exhibiting the pH-dependent aggregation and magnetic relaxation behavior. The pH-dependent behavior of the NPs derives from the easy protonation of the apical hydroxo ligands of [{ReS}(CN)(OH)] cluster, which triggers partial leaching of Mn ions and aggregation of the NPs driven by the surface neutralization.

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The silica nanoparticles (SNs) co-doped with paramagnetic ([Mn(HL)],) and luminescent ([Ru(dipy)]) complexes are represented. The specific distribution of [Mn(HL)] within the SNs allows to achieve about ten-fold enhancing in magnetic relaxivities in comparison with those of [Mn(HL)] in solutions. The leaching of [Mn(HL)] from the shell can be minimized through the co-doping of [Ru(dipy)] into the core of the SNs.

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This work presents the synthesis of a new representative of hemicurcuminoids with a nonyloxy substituent () as a fluorescent amphiphilic structural element of vesicular aggregates based on phosphatidylcholine (PC), phosphatidylserine (PS), and 10,12-pentacosadiynoic acid (PCDA). Both X-ray diffraction analysis of the single crystal and H NMR spectra of in organic solvents indicate the predominance of the enol-tautomer of . DFT calculations show the predominance of the enol tautomer in supramolecular assemblies with PC, PS, and PCDA molecules.

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The present work introduces rational design of nanoparticulate Mn(II)-based contrast agents through both variation of the μ (inner) ligands within a series of hexarhenium cluster complexes [{Re(μ-Q)}(CN)] (ReQ, Q = S, Se or Te) and interfacial decoration of the nanoparticles (NPs) KMnReQ ( = 1.3 - 1.8) by a series of pluronics (F-68, P-123, F-127).

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A series of dialkylaminostyrylhetarene dyes constructed from electron-rich and electron-deficient moieties of various structures connected via vinylene π-bridges are introduced as temperature-sensitive luminophores. The temperature dependent emission of the dyes in the acidified dichloromethane solutions derives from temperature-induced shift of the equilibrium between neutral and protonated forms of the dyes. The heating-induced blue shift and intensification of emission of neutral form of the dyes make them a promising basis for development of nanoparticles exhibiting temperature-sensitivity in aqueous solutions at pH typical of biological liquids.

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New octahedral rhenium cluster complexes [{ReQ}(SO)] (Q = S or Se) were synthesized starting from [{ReQ}(HO)(OH)]·12HO. The complexes were crystallized as sodium salts and characterized by X-ray single-crystal diffraction and elemental analyses, IR, UV/vis and luminescence spectroscopies. Magnetic relaxation data demonstrate the complex formation of the cluster units with gadolinium ions.

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The present work introduces Gd3+ complexes with giant keplerate polyanions as a promising basis for MRI contrast agents. The impact of Gd3+ binding with different building blocks of keplerates on the magnetic relaxivity of the complexes is revealed by comparative study of the keplerates [{Mo6O21}12{Mo2O4(OAc)}30]42-, [{Mo6O21}12{Mo2O4(HPO4)}30]72-, and [{Mo6O21}12{Mo2O2S2(OAc)}30]42-. Unprecedentedly high longitudinal and transverse relaxivity values (up to 250 and 300 mM-1 s-1 correspondingly) are achieved for the keplerates possessing edl{Mo2O4(OAc)} and {Mo2O4(HPO42-)} moieties under their 1 : 1 complex formation with Gd3+.

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