Ilja Ignatjev

Ilja Ignatjev
Center for Physical Sciences and Technology | CPST · Organic Chemistry

About

46
Publications
6,471
Reads
How we measure 'reads'
A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text. Learn more
484
Citations

Publications

Publications (46)
Article
Full-text available
Utilizing a large portion of shrimp biowaste into valuable materials such as chitosan is one of the most required actions to sustain shrimp waste and promote green deal targets and circular economy principles in the aquaculture industry. This research aimed to optimize acidic demineralization using various HCl concentrations of 1, 2, 3, 4, 5, and 1...
Article
Full-text available
Cementitious materials are used to construct an engineered barrier in repositories for radioactive waste. The cement matrix may contain a variety of organic compounds, some of which are polymeric admixtures used as plasticizers. Superplasticizers (SPs) are highly effective organic cement additives for reducing water amount, increasing workability,...
Article
Full-text available
Generation of hybrid gold-silver nanoparticles from different metal ratios by thermal heating thin metal films on a glass surface with a nanosecond pulsed laser is presented. The optical properties of obtained nanoparticles are dependent on localized surface plasmon resonance (LSPR), which can be tuned in the range of 400–530 nm by varying the rati...
Article
Full-text available
Epitaxial lateral overgrowth (ELO) of GaN epilayers on a sapphire substrate was studied by using a laser-patterned graphene interlayer. Monolayer graphene was transferred onto the sapphire substrate using a wet transfer technique, and its quality was confirmed by Raman spectroscopy. The graphene layer was ablated using a femtosecond laser, which pr...
Article
Full-text available
To fabricate graphene-based high-frequency electronic and optoelectronic devices, there is a high demand for scalable low-contaminated graphene with high mobility. Graphene synthesized via chemical vapor deposition (CVD) on copper foil appears promising for this purpose, but residues from the polymethyl methacrylate (PMMA) layer, used for the wet t...
Article
In this study, two types of biosorbents were used to remove ¹³⁷Cs and plutonium isotopes from aqueous solutions - moss (Ptilium crista - castrensis) and oak sawdust (Quercus robur), both in the form of natural and modified state. Sorbent modification significantly increases the sorbent surface area (for moss sorbents - from 4.0 to 47.2 m²/g, and fo...
Article
Full-text available
The remote epitaxy of GaN epilayers on GaN/sapphire templates was studied by using different graphene interlayer types. Monolayer, bilayer, double-stack of monolayer, and triple-stack of monolayer graphenes were transferred onto GaN/sapphire templates using a wet transfer technique. The quality of the graphene interlayers was examined by Raman spec...
Article
Full-text available
Graphene research and technology development requires to reveal adsorption processes and understand how the defects change the physicochemical properties of the graphene-based systems. In this study, shell-isolated nanoparticle-enhanced Raman spectroscopy (SHINERS) and graphene-enhanced Raman spectroscopy (GERS) coupled with density functional theo...
Article
Keywords: multi-walled carbon nanotubes (MWCNT), iridium-doped, nanohybrid composite, Raman spectrum, energy-dispersive X-ray spectroscopy Multi-walled carbon nanotubes have been prepared by chemical vapour deposition pyrolysis of ethyl alcohol at 665°C. The addition of atoms other than carbon to the nanostructure, in our case the iridium component...
Article
Full-text available
Surface-enhanced Raman spectroscopy (SERS) substrates fabricated using a repeated laser treatment of thin gold films are demonstrated. The presented SERS substrates consist of the gold nanoparticles, whose density and size depend on the used film thickness and number of treated films. The larger number of the treated gold film layers increases the...
Article
Full-text available
Two kinds of natural silicate garnets from the known origin countries were investigated: pyralspites – pyrope (Russia), almandine (India), rhodolite (India), spessartine (India), blue colour-change garnet (Sri Lanka), and ugrandites – andradite (Russia), demantoid (Russia), topazolite (Russia), rainbow garnet (Japan), grossular (Kenya-Tanzania), co...
Article
This study aims to characterize the irradiated RBMK-1500 nuclear graphite in terms of both structural and radiological properties. The experimental results of morphological and structural analysis of the irradiated graphite samples by using SEM, Raman spectroscopy as well as the theoretical evaluation of primary displacement damage are presented. M...
Article
Full-text available
Remote epitaxy via graphene has recently attracted significant attention, since it provides the possibility to lift-off the grown epitaxial layer, reuse the substrate, and produce flexible devices. However, extensive research is still necessary to fully understand the III-nitride formation on the van der Waals surface of a two-dimensional material...
Article
Indium nitride epilayers were grown by metalorganic chemical vapour deposition (MOCVD) on graphene/SiC substrates with different terrace widths. Photoluminescence (PL) properties in the epilayers of different thickness and along the epilayer growth direction were studied with spatial resolution using confocal microscopy. The PL properties have been...
Article
Shell-isolated nanoparticles spread over the surface of sample material are widely used in various fields of analysis. Their stability has not yet been well established. In this report, the silica shell-isolated gold nanospheres were synthesized in aqueous medium. Their stability in water and 17 organic solvents was observed visually and employing...
Article
Studying the biochemistry of yeast cells has enabled scientists to understand many essential cellular processes in human cells. Further development of biotechnological and medical progress requires revealing surface chemistry in living cells by using a non-destructive and molecular structure sensitive technique. In this study shell-isolated nanopar...
Article
Full-text available
The properties of the planar junction between graphene layer and thin film metal structures are important for formation of the electronic devices integrating the structures of the two-dimensional materials. However, the properties of the graphene-metal contacts are still weakly controlled in the large area device fabrication. In this report for the...
Article
Concentric microring structures containing gold nanoparticles were fabricated using a Bessel-like beam array with the 30 μm and 60 μm periods. The fabricated structures coated with 5 nm thick gold layer demonstrate enhancement of Raman signals due to their induced localized plasmon resonance. The measured Raman signal intensity of self-assembled mo...
Article
Full-text available
Oxidised aluminum coatings are useful in various high technology applications to protect surfaces from negative environmental effects. In this study, aluminum discs and foils of industrial alloys were anodised in a sulphuric acid/oxalic acid electrolyte. Scanning electron microscopy was used to determine the pore diameter, distribution and surface...
Article
Electrochemically synthesised poly-L-lysine (PLL) was employed to attach functionalised graphene (fG) to the electrode surface. The electropolymerisation conditions such as pH, monomer concentration, potential scan rate and number of cycles were optimised. Despite reports in the literature about electrochemical synthesis of PLL at pH between 8 and...
Article
Formation of a self-assembled monolayer onto the polycrystalline gold substrate from thiols containing a terminal phenylalanine (Phe) ring and intrachain amide groups (HS-(CH2)7-CONH-(CH2)2-C6H5) was characterized by vibrational sum frequency generation (SFG) spectroscopy. The temporal evolution of the characteristic Phe ring stretching vibration ν...
Article
Electropolymerisation of riboflavin (Rf) was performed in different media in order to optimise the best conditions for the creation of a stable and electroactive polymerised riboflavin (PRf) film. Electropolymerisation was performed using cyclic voltammetry (CV) in solutions with various pH in different potential windows. Different electrode substr...
Article
Utilizing surface-immobilized synthetic lipid substrates containing the redox-active ferrocene groups, the enzymatic activity of lipase from Thermomyces lanuginosus was measured by the cyclic voltammetry method. The activity was correlated with the surface density of the protein by the ATR-IR spectroscopy and the total internal reflection ellipsome...
Article
Full-text available
In this study, the metallisation of acrylonitrile-butadiene-styrene (ABS) plastics has been investigated. The adhesion of the metallic layer on ABS was studied by the cross-cut test. Raman spectroscopy was used to evaluate the components of ABS plastics. The results indicate that Raman spectroscopy can be applied for rapid determination of suitabil...
Article
Raman (RS), surface-enhanced Raman scattering (SERS), electrochemistry, and isotopic effect methods were used to characterize selective adsorption of two isotopically labeled bradykinin analogues, [(Phe-D5)5]BK and [(Phe-D5)8]BK, a hormone which is known to be involved in small-cell and non-small-cell lung carcinoma and prostate cancer. The investi...
Article
Surface-enhanced Raman scattering, electrochemistry, and generalized two-dimensional correlation analysis (G2DCA) methods were used to characterize bradykinin (BK), a hormone which is known to be involved in small-cell and non-small-cell lung carcinoma and prostate cancer. BK was deposited onto Ag, Au, and Cu electrode surfaces under different appl...
Article
Full-text available
Adsorption of decapeptide neuromedin B (NMB) on copper electrode has been investigated by in situ surface-enhanced Raman scattering (SERS) spectroelectrochemistry in the temperature interval from 12 to 72 °C at -0.600 and -1.000 V potentials. It was found that intensities of peptide bands decrease at temperatures above 30 °C with higher decrease sl...
Article
Surface-enhanced Raman scattering, electrochemistry, and generalized two-dimensional correlation analysis methods were used to characterize phyllolitorin and a peptide derived from Pseudophryne guntheri (PG-L). Phyllolitorin and PG-L were deposited onto Ag, Au, and Cu electrode surfaces at different applied electrode potentials in an aqueous soluti...
Article
Full-text available
Surface-enhanced Raman scattering (SERS), electrochemistry, and generalized two-dimensional correlation analysis (G2DCA) methods were used to define neuromedin B (NMB) ordered superstructures on Ag, Au, and Cu electrode surfaces at different applied electrode potentials in an aqueous solution at physiological pH. The orientation of NMB and the adso...
Article
Full-text available
We demonstrate a method for simultaneous structure and function determination of integral membrane proteins. Electrical impedance spectroscopy shows that Staphylococcus aureus alpha-hemolysin channels in membranes tethered to gold have the same properties as those formed in free-standing bilayer lipid membranes. Neutron reflectometry provides high-...
Article
Full-text available
This paper presents computational modeling of response kinetics of bioelectroanalytical system based on solid supported lipase substrate and lipase interaction. The model assumes that lipase substrate is formed by dripping and drying a small amount of the ethanol solution of 9-(5’-ferrocenylpentanoyloxy)nonyl disulfide (FPONDS) and that lipase...
Article
Surface plasmon resonance ellipsometry (SPRE) was used to investigate a multilayer system produced by Thermomyces Lanuginosus lipase (TLL) deposited from buffer solution onto chemically formed octadecanthiole (ODT) self-assembled monolayer grown on a gold surface. The angular dependence of the ellipsometric parameters ψ and Δ was also investigated...
Article
The infrared-visible sum-frequency generation (SFG) vibrational spectroscopy was used to probe enzymatic activity of Thermomyces lanuginosus lipase (TLL) at air/water interface. A monolayer of amphiphilic O-palmitoyl-2,3-dicyanohydroquinone (PDCHQ), containing target ester group and two CN groups serving as vibrational markers, was utilized as an e...
Article
Full-text available
This paper presents computational modeling of response kinetics of bioelectroanalytical system based on the interfacial action of enzyme lipas e. The model also assumes that the substrate of enzyme is located on the surface of micelles which are spread in the solution under study. Two distinct mathematical models have been developed and evaluated t...
Article
Full-text available
In our previous work was showed that the SPR technique is very effective for in situ observation of the lipase interaction with MNFcP (9 merkaptononyl – 5' – ferrocenylpentanoate). However, the investigation was performed with only monochromatic 633nm light at the beginning and at the end of the reaction. In this work, the results of the investigat...
Article
Full-text available
The surface plasmon resonance method was used for determination of 9-(5'-ferrocenylpentanoyloxy) nonyl disulfide (FPONDS) and lipase thin film thicknesses and optical constants. Surface plasmons were excited in the Kretchmann con-figuration on the thin 50 nm gold film on the BK7 or SF10 glass prism. Sufficient sensitivity of the method for investig...
Article
A novel electrochemical technique for the general assay of lipase activity is described. The method utilizes a solid-supported lipase substrate, which is formed by dripping and drying a small amount of an ethanol solution of 9-(5'-ferrocenylpentanoyloxy)nonyl disulfide (FPONDS) onto gold modified by a hexanethiol self-assembled monolayer. The redox...
Article
The possibility to oxidise electrochemically 5-(6-methyl-2,4-dioxo-1,2,3,4-tetrahydro-3-pyrimidinyl)-methyl-1,3,4-oxadiazole-2-thione was investiga-ted in order to synthesise its oxygen analogue. However, we have disco-vered that while using Pt electrodes the yield of the reaction is very low due to passivation of metal surface, caused by the irrev...

Network

Cited By