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Suslova EV, Ulyanov AN, Kozlov AP, Shashurin DA, Savilov SV, Chelkov GA. Composition and Electronic Structure of La 2O 3/CNFs@C Core-Shell Nanoparticles with Variable Oxygen Content. NANOMATERIALS (BASEL, SWITZERLAND) 2023; 13:2945. [PMID: 37999299 PMCID: PMC10674885 DOI: 10.3390/nano13222945] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2023] [Revised: 11/08/2023] [Accepted: 11/10/2023] [Indexed: 11/25/2023]
Abstract
La2O3 nanoparticles stabilized on carbon nanoflake (CNF) matrix were synthesized and graphitized to produce core-shell structures La2O3/CNFs@C. Further oxidation of these structures by nitric acid vapors for 1, 3 or 6 h was performed, and surface-oxidized particles La2O3/CNFs@C_x (x = 1, 3, 6) were produced. Bulk and surface compositions of La2O3/CNFs@C and La2O3/CNFs@C_x were investigated by thermogravimetric analysis and X-ray photoelectron spectroscopy. With increasing the duration of oxidation, the oxygen and La2O3 content in the La2O3/CNFs@C_x samples increased. The electronic structures of samples were assessed by electron paramagnetic resonance. Two paramagnetic centers were associated with unpaired localized and mobile electrons and were registered in all samples. The correlation between bulk and surface compositions of the samples and their electronic structures was investigated for the first time. The impact of the ratio between sp2- and sp3-hybridized C atoms, the number and nature of oxygen-containing groups on the surface and the presence and proportion of coordinated La atoms on the EPR spectra was demonstrated.
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Affiliation(s)
- Evgeniya V. Suslova
- Department of Chemistry, Lomonosov Moscow State University, 119991 Moscow, Russia (A.P.K.)
| | - Alexander N. Ulyanov
- Department of Chemistry, Lomonosov Moscow State University, 119991 Moscow, Russia (A.P.K.)
| | - Alexey P. Kozlov
- Department of Chemistry, Lomonosov Moscow State University, 119991 Moscow, Russia (A.P.K.)
| | - Denis A. Shashurin
- Faculty of Medicine, Lomonosov Moscow State University, 119991 Moscow, Russia
| | - Serguei V. Savilov
- Department of Chemistry, Lomonosov Moscow State University, 119991 Moscow, Russia (A.P.K.)
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Ladikan O, Silyavka E, Mitrofanov A, Laptenkova A, Shilovskikh V, Kolonitckii P, Ivanov N, Remezov A, Fedorova A, Khripun V, Pestova O, Podolskaya EP, Sukhodolov NG, Selyutin AA. Thin Films of Lanthanide Stearates as Modifiers of the Q-Sense Device Sensor for Studying Insulin Adsorption. ACS OMEGA 2022; 7:24973-24981. [PMID: 35910105 PMCID: PMC9330115 DOI: 10.1021/acsomega.1c07300] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/27/2021] [Accepted: 06/30/2022] [Indexed: 06/15/2023]
Abstract
This article presents new possibilities of using thin films of lanthanide stearates as sorbent materials. Modification of the Q-sense device resonator with monolayers of lanthanide stearates by the Langmuir-Schaeffer method made it possible to study the process of insulin protein adsorption on the surface of new thin-film sorbents. The resulting films were also characterized by compression isotherms, chemical analysis, scanning electron microscopy, and mass spectrometry. The transition of stearic acid to salt was recorded by IR spectroscopy. Using the LDI MS method, the main component of thin films, lanthanide distearate, was established. The presence of Eu2+ in thin films was revealed. In the case of europium stearate, the maximum value of insulin adsorption was obtained, -1.67·10-10 mole/cm2. The findings suggest the possibility of using thin films of lanthanide stearates as a sorption material for the proteomics determination of the quantitative protein content in complex fluid systems by specific adsorption on modified surfaces and isolation of such proteins from complex mixtures.
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Affiliation(s)
- Olga Ladikan
- St.
Petersburg State University, Universitetskaya emb. 7-9, 199034 St. Petersburg, Russia
| | - Elena Silyavka
- St.
Petersburg State University, Universitetskaya emb. 7-9, 199034 St. Petersburg, Russia
| | - Andrei Mitrofanov
- St.
Petersburg State University, Universitetskaya emb. 7-9, 199034 St. Petersburg, Russia
- Leibniz-Institut
für Polymerforschung Dresden e.V., Hohe Str. 6, 01069 Dresden, Germany
| | - Anastasia Laptenkova
- St.
Petersburg State University, Universitetskaya emb. 7-9, 199034 St. Petersburg, Russia
| | - Vladimir Shilovskikh
- St.
Petersburg State University, Universitetskaya emb. 7-9, 199034 St. Petersburg, Russia
| | - Petr Kolonitckii
- St.
Petersburg State University, Universitetskaya emb. 7-9, 199034 St. Petersburg, Russia
| | - Nikita Ivanov
- St.
Petersburg State University, Universitetskaya emb. 7-9, 199034 St. Petersburg, Russia
| | - Andrey Remezov
- St.
Petersburg State University, Universitetskaya emb. 7-9, 199034 St. Petersburg, Russia
| | - Anna Fedorova
- St.
Petersburg State University, Universitetskaya emb. 7-9, 199034 St. Petersburg, Russia
| | - Vassily Khripun
- St.
Petersburg State University, Universitetskaya emb. 7-9, 199034 St. Petersburg, Russia
| | - Olga Pestova
- St.
Petersburg State University, Universitetskaya emb. 7-9, 199034 St. Petersburg, Russia
| | - Ekaterina P. Podolskaya
- Golikov
Research Center of Toxicology, Bekhtereva Street 1, 192019 St. Petersburg, Russia
- Institute
for Analytical Instrumentation of the Russian Academy of Science, Ivana Chernykh Street 31-33 lit.
A, 198095 St. Petersburg, Russia
| | - Nikolai G. Sukhodolov
- St.
Petersburg State University, Universitetskaya emb. 7-9, 199034 St. Petersburg, Russia
- Institute
for Analytical Instrumentation of the Russian Academy of Science, Ivana Chernykh Street 31-33 lit.
A, 198095 St. Petersburg, Russia
| | - Artem A. Selyutin
- St.
Petersburg State University, Universitetskaya emb. 7-9, 199034 St. Petersburg, Russia
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