Ruslan Garifullin - Academia.edu (original) (raw)

Papers by Ruslan Garifullin

Materials Today Bio, 2021

The electroactivity as a supramolecular feature of intelligently designed self-assembled systems ... more The electroactivity as a supramolecular feature of intelligently designed self-assembled systems stimulates a wide interest in development of new stimuli-responsive biomaterials. A diverse set of nanostructures are fabricated through programmed self-assembly of molecules for functional materials. Electroactive groups are conjugated as a functional moiety for organic semiconductor applications. In this review, we present recent examples of selfassembling peptide molecules and electroactive units for supramolecular functional electronic and optical materials with potential biomedical and bioelectronics applications.

Materials Science and Engineering: C, 2021

Synthetic oligopeptides are a promising alternative to natural full-length growth factors and ext... more Synthetic oligopeptides are a promising alternative to natural full-length growth factors and extracellular matrix (ECM) proteins in tissue regeneration and therapeutic angiogenesis applications. In this work, angiogenic properties of dual and triple compositions containing RGD, GHK peptides and copper (II) ions (Cu2+) were for the first time studied. To reveal specific in vitro effects of these compositions in threedimensional scaffold, adamantyl group bearing peptides, namely Ada-Ahx-GGRGD (1) and Ada-Ahx-GGGHK (2), were effectively immobilized in bioinert pHEMA macroporous cryogel via host-guest βcyclodextrin-adamantane interaction. The cryogels were additionally functionalized with Cu2+ via the formation of GHK-Cu complex. Angiogenic responses of HUVECs grown within the cryogel ECM model were analyzed. The results demonstrate that the combination of RGD with GHK and further with Cu2+ dramatically increases cell proliferation, differentiation, and production of a series of angiogenesis related cytokines and growth factors. Furthermore, the level of glutathione, a key cellular antioxidant and redox regulator, was altered in relation to the angiogenic effects. These results are of particular interest for establishing the role of multiple peptide signals on regeneration related processes and for developing improved tissue engineering materials.

Materials Advances, 2021

This study reveals enhanced cancer-targeting properties of peptide composition consisting of RGD ... more This study reveals enhanced cancer-targeting properties of peptide composition consisting of RGD and GHK recognized as important cell adhesion factor and pleiotropic modulator of cellular functions, respectively. C12-GGRGD-NH2 and C12-GGGHK-NH2...

Proceedings of 6th International Electronic Conference on Medicinal Chemistry, 2020

ACS Applied Bio Materials, 2019

Oligopeptides are versatile cell modulators resembling pleiotropic activities of ECM proteins and... more Oligopeptides are versatile cell modulators resembling pleiotropic activities of ECM proteins and growth factors. Studying the role of cellinstructive peptide signals within 3D scaffolds, yet poorly known, requires effective approaches to introducing bioactive sequences into appropriate materials. We synthesized RGD and GHK motif based peptides 1 and 2 linked to the terminal adamantyl group (Ad) and their fluorescent derivatives 3 and 4. Poly(hydroxyethyl methacrylate) (pHEMA) cryogels with additional PEG/βcyclodextrin (CD) units were prepared as an inert macroporous scaffold capable to bind the adamantylated peptides via affinity CD-Ad complexation. According to toluidine blue staining, the CD moieties were effectively and stably incorporated in the pHEMA cryogels at nanomolar amounts per milligram of material. The CD component gradually increased the thickness and swelling ability of the polymer walls of cryogels, resulting in a noticeable decrease in macropore size and modulation of viscoelastic properties. The labeled peptides exhibited fast kinetics of specific binding to the CD-modified cryogels and were simultaneously immobilized by coincubation. The peptide loading approached ca. 0.31 mg per cm 2 of cryogel sheet. A well-defined mitogenic effect of the immobilized peptides (2 < 1≪ 1 + 2) was revealed toward 3T3 and PC-12 cells. The synergistic action of RGD and GHK peptides induced a profound change in cell behavior/morphology attributed to a growth-factor-like activity of the composition. Altogether, our results provide an effective procedure for the preparation of CDmodified pHEMA cryogels and their uniform in situ functionalization with bioactive peptide(s) of interest and an informative study of cellular responses in the functionalized scaffolds.

Frontiers in Pharmacology, 2018

Although delocalized lipophilic cations have been identified as effective cellular and mitochondr... more Although delocalized lipophilic cations have been identified as effective cellular and mitochondrial carriers for a range of natural and synthetic drug molecules, little is known about their effects on pharmacological properties of peptides. The effect of triphenylphosphonium (TPP) cation on bioactivity of antioxidant tetrapeptides based on the model opioid YRFK motif was studied. Two tetrapeptide variants with L-arginine (YRFK) and D-arginine (YrFK) were synthesized and coupled with carboxyethyl-TPP (TPP-3) and carboxypentyl-TPP (TPP-6) units. The TPP moiety noticeably promoted YRFK cleavage by trypsin, but effectively prevented digestion of more resistant YrFK attributed, respectively, to structure-organizing and shielding effects of the TPP cation on conformational variants of the tetrapeptide motif. The TPP moiety enhanced radical scavenging activity of the modified YRFK in a model Fenton-like reaction, whereas decreased reactivity was revealed for both YrFK and its TPP derivative. The starting motifs and modified oligopeptides, especially the TPP-6 derivatives, suppressed acute oxidative stress in neuronal PC-12 cells during a brief exposure similarly with glutathione. The effect of oligopeptides was compared upon culturing of PC-12 cells with CoCl 2 , L-glutamic acid, or menadione to mimic physiologically relevant oxidative states. The cytoprotective activity of oligopeptides significantly depended on the type of oxidative factor, order of treatment and peptide structure. Pronounced cell-protective effect was established for the TPP-modified oligopeptides, which surpassed that of the unmodified motifs. The protease-resistant TPP-modified YrFK showed the highest activity when administered 24 h prior to the cell damage. Our results suggest that the TPP cation can be used as a modifier for small therapeutic peptides to improve their pharmacokinetic and pharmacological properties.

European Biophysics Journal, 2018

Macromolecular bioscience, Jan 10, 2018

Dentin phosphoprotein (DPP) is a major component of the dentin matrix playing crucial role in hyd... more Dentin phosphoprotein (DPP) is a major component of the dentin matrix playing crucial role in hydroxyapatite deposition during bone mineralization, making it a prime candidate for the design of novel materials for bone and tooth regeneration. The bioactivity of DPP-derived proteins is controlled by the phosphorylation and dephosphorylation of the serine residues. Here an enzyme-responsive peptide nanofiber system inducing biomineralization is demonstrated. It closely emulates the structural and functional properties of DPP and facilitates apatite-like mineral deposition. The DPP-mimetic peptide molecules self-assemble through dephosphorylation by alkaline phosphatase (ALP), an enzyme participating in tooth and bone matrix mineralization. Nanofiber network formation is also induced through addition of calcium ions. The gelation process following nanofiber formation produces a mineralized extracellular matrix like material, where scaffold properties and phosphate groups promote minera...

Biomacromolecules, Jan 25, 2017

Chirality and morphology are essential factors for protein function and interactions with other b... more Chirality and morphology are essential factors for protein function and interactions with other biomacromolecules. Extracellular matrix (ECM) proteins are also similar to other proteins in this sense; however, the complexity of the natural ECM makes it difficult to study these factors at the cellular level. The synthetic peptide nanomaterials harbor great promise in mimicking specific ECM molecules as model systems. In this work, we demonstrate that mechanosensory responses of stem cells are directly regulated by the chirality and morphology of ECM-mimetic peptide nanofibers with strictly controlled characteristics. Structural signals presented on L-amino acid containing cylindrical nanofibers (L-VV) favored the formation of integrin 1-based focal adhesion complexes, which increased the osteogenic potential of stem cells through the activation of nuclear YAP. On the other hand, twisted ribbon-like nanofibers (L-FF and D-FF) guided the cells into round shapes and decreased the format...

physica status solidi (a), 2016

Here peptide amphiphile (PA) nanofiber network is exploited as a three-dimensional soft template ... more Here peptide amphiphile (PA) nanofiber network is exploited as a three-dimensional soft template to construct anatase TiO 2 and wurtzite ZnO nanonetworks. Atomic layer deposition (ALD) technique is used to coat the organic nanonetwork template with TiO 2 and ZnO. ALD method enables uniform and conformal coatings with precisely controlled TiO 2 and ZnO thickness. The resulting semiconducting metal oxide nanonetworks are utilized as anodic materials in dye-sensitized solar cells. Effect of metal oxide layer thickness on device performance is studied. The devices based on thin TiO 2 coatings (<10 nm) demonstrate considerable dependence on material thickness, whereas thicker (>17 nm) ZnO-based devices do not show an explicit correlation.

ACS Applied Materials & Interfaces, 2016

Template-directed synthesis of nanomaterials can provide benefits such as small crystalline size,... more Template-directed synthesis of nanomaterials can provide benefits such as small crystalline size, high surface area, large surface-to-volume ratio, and structural stability. These properties are important for shorter distance in ion/electron movement and better electrode surface/electrolyte contact for energy storage applications. Here nanostructured FePO 4 cathode materials were synthesized by using peptide nanostructures as a template inspired by biomineralization process. The amorphous, high surface area FePO 4 nanostructures were utilized as a cathode for lithium-ion batteries. Discharge capacity of 155 mAh/g was achieved at C/20 current rate. The superior properties of biotemplated and nanostructured amorphous FePO 4 are shown compared to template-free crystalline FePO 4 .

SPIE Proceedings, 2015

Recent experimental research efforts on developing functional nanostructured III-nitride and meta... more Recent experimental research efforts on developing functional nanostructured III-nitride and metal-oxide materials via low-temperature atomic layer deposition (ALD) will be reviewed. Ultimate conformality, a unique propoerty of ALD process, is utilized to fabricate core-shell and hollow tubular nanostructures on various nano-templates including electrospun nanofibrous polymers, self-assembled peptide nanofibers, metallic nanowires, and multi-wall carbon nanotubes (MWCNTs). III-nitride and metal-oxide coatings were deposited on these nano-templates via thermal and plasma-enhanced ALD processes with thickness values ranging from a few mono-layers to 40 nm. Metal-oxide materials studied include ZnO, TiO2, HfO2, ZrO2, and Al2O3. Standard ALD growth recipes were modified so that precursor molecules have enough time to diffuse and penetrate within the layers/pores of the nano-template material. As a result, uniform and conformal coatings on high-surface area nano-templates were demonstrated. Substrate temperatures were kept below 200C and within the self-limiting ALD window, so that temperature-sensitive template materials preserved their integrity III-nitride coatings were applied to similar nano-templates via plasma-enhanced ALD (PEALD) technique. AlN, GaN, and InN thin-film coating recipes were optimized to achieve self-limiting growth with deposition temperatures as low as 100C. BN growth took place only for >350C, in which precursor decomposition occured and therefore growth proceeded in CVD regime. III-nitride core-shell and hollow tubular single and multi-layered nanostructures were fabricated. The resulting metal-oxide and III-nitride core-shell and hollow nano-tubular structures were used for photocatalysis, dye sensitized solar cell (DSSC), energy storage and chemical sensing applications. Significantly enhanced catalysis, solar efficiency, charge capacity and sensitivity performance are reported. Moreover, core-shell metal-oxide and III-nitride materials showed promise to be used in applications where flexibility is critical like functional membranes, textile and flexible electronic applications.

Chemical Communications, 2015

Induced supramolecular chirality was investigated in the self-assembled peptide amphiphile (PA) n... more Induced supramolecular chirality was investigated in the self-assembled peptide amphiphile (PA) nanosystems.

Photochemistry and Photobiology, 2014

The design and synthesis of a phthalocyanine-Gd-DOTA conjugate is presented to open the way to no... more The design and synthesis of a phthalocyanine-Gd-DOTA conjugate is presented to open the way to novel molecular theranostics, combining the properties of MRI contrast imaging with photodynamic therapy. The rational design of the conjugate integrates isomeric purity of the phthalocyanine core substitution, suitable biocompatibility with the use of polyoxo water-solubilizing substituents, and a convergent synthetic strategy ended by the use of click chemistry to graft the Gd-DOTA moiety to the phthalocyanine. Photophysical and photochemical properties, contrast imaging experiments and preliminary in vitro investigations proved that such a combination is relevant and lead to a new type of potential theranostic agent.

RSC Advances, 2013

Peptide-polymer nanofibrous networks can be developed to obtain hybrid systems providing both fun... more Peptide-polymer nanofibrous networks can be developed to obtain hybrid systems providing both functionalities of peptides and stability and processability of the polymers. In this work, a bio-inspired heavy metal binding peptide was synthesized and noncovalently immobilized on water-insoluble electrospun hydroxypropyl-beta-cyclodextrin nanofibers (CDNF). The peptide functionalized hybrid nanofibers were able to bind to heavy metal ions and facilitated removal of metal ions from water. The peptide-polymer scavenging system has potential for development of further molecular recognition systems with various peptide sequences or host-guest inclusion complexes.

Scientific Reports, 2013

A solvent-free fabrication of TiO 2 and ZnO nanonetworks is demonstrated by using supramolecular ... more A solvent-free fabrication of TiO 2 and ZnO nanonetworks is demonstrated by using supramolecular nanotemplates with high coating conformity, uniformity, and atomic scale size control. Deposition of TiO 2 and ZnO on three-dimensional nanofibrous network template is accomplished. Ultrafine control over nanotube diameter allows robust and systematic evaluation of the electrochemical properties of TiO 2 and ZnO nanonetworks in terms of size-function relationship. We observe hypsochromic shift in UV absorbance maxima correlated with decrease in wall thickness of the nanotubes. Photocatalytic activities of anatase TiO 2 and hexagonal wurtzite ZnO nanonetworks are found to be dependent on both the wall thickness and total surface area per unit of mass. Wall thickness has effect on photoexcitation properties of both TiO 2 and ZnO due to band gap energies and total surface area per unit of mass. The present work is a successful example that concentrates on nanofabrication of intact three-dimensional semiconductor nanonetworks with controlled band gap energies.

Journal of Materials Chemistry A, 2013

One-dimensional titania nanostructures can serve as a support for light absorbing molecules and r... more One-dimensional titania nanostructures can serve as a support for light absorbing molecules and result in an improvement in the short circuit current (J sc) and open circuit voltage (V oc) as a nanostructured and high-surface-area material in dye-sensitized solar cells. Here, self-assembled amyloid-like peptide nanofibers were exploited as an organic template for the growth of one-dimensional titania nanostructures. Nanostructured titania layers were utilized as anodic materials in dye sensitized solar cells (DSSCs). The photovoltaic performance of the DSSC devices was assessed and an enhancement in the overall cell performance compared to unstructured titania was observed.