1
|
Dwivedi N, Siddiqui MA, Srivastava S, Sinha N. 1 H- 13 C cross-polarization kinetics to probe hydration-dependent organic components of bone extracellular matrix. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2023; 61:397-406. [PMID: 36946081 DOI: 10.1002/mrc.5347] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Revised: 02/17/2023] [Accepted: 03/19/2023] [Indexed: 06/09/2023]
Abstract
Bone is a living tissue made up of organic proteins, inorganic minerals, and water. The organic component of bone (mainly made up of Type-I collagen) provides flexibility and tensile strength. Solid-state nuclear magnetic resonance (ssNMR) is one of the few techniques that can provide atomic-level structural insights of such biomaterials in their native state. In the present article, we employed the variable contact time cross-polarization (1 H-13 C CP) kinetics experiments to study the hydration-dependent atomic-level structural changes in the bone extracellular matrix (ECM). The natural abundant 13 C CP intensity of the bone ECM is measured by varying CP contact time and best fitted to the nonclassical kinetic model. Different relaxation parameters were measured by the best-fit equation corresponding to the different hydration conditions of the bone ECM. The associated changes in the measured parameters due to varying levels of hydration observed at different sites of collagen protein have provided its structural arrangements and interaction with water molecules in bone ECM. Overall, the present study reveals a better understanding of the kinetics of the organic part inside the bone ECM that will help in comprehending the disease-associated pathways.
Collapse
Affiliation(s)
- Navneet Dwivedi
- Centre of Biomedical Research, SGPGIMS Campus, Raebareli Road, Lucknow, 226014, India
- Department of Physics, Integral University, Lucknow, 226026, India
| | - Mohd Adnan Siddiqui
- Centre of Biomedical Research, SGPGIMS Campus, Raebareli Road, Lucknow, 226014, India
| | - Seema Srivastava
- Department of Physics, Integral University, Lucknow, 226026, India
| | - Neeraj Sinha
- Centre of Biomedical Research, SGPGIMS Campus, Raebareli Road, Lucknow, 226014, India
| |
Collapse
|
2
|
Valentini C, Montes-García V, Livio PA, Chudziak T, Raya J, Ciesielski A, Samorì P. Tuning the electrical properties of graphene oxide through low-temperature thermal annealing. NANOSCALE 2023; 15:5743-5755. [PMID: 36880730 DOI: 10.1039/d2nr06091d] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
During the last fifteen years, the reduction of electrically insulating graphene oxide (GO) through the elimination of oxygen containing functional groups and the restoration of sp2 conjugation yielding its conducting form, known as reduced graphene oxide (rGO), has been widely investigated as a scalable and low-cost method to produce materials featuring graphene-like characteristics. Among various protocols, thermal annealing represents an attractive green approach compatible with industrial processes. However, the high temperatures typically required to accomplish this process are energetically demanding and are incompatible with the use of plastic substrates often desired for flexible electronics applications. Here, we report a systematic study on the low-temperature annealing of GO by optimizing different annealing conditions, i.e., temperature, time, and reduction atmosphere. We show that the reduction is accompanied by structural changes of GO, which affect its electrochemical performance when used as an electrode material in supercapacitors. We demonstrate that thermally-reduced GO (TrGO) obtained under air or inert atmosphere at relatively low temperatures (<300 °C) exhibits low film resistivities (10-2-10-4 Ω m) combined with unaltered resistance after 2000 bending cycles when supported on plastic substrates. Moreover, it exhibits enhanced electrochemical characteristics with a specific capacitance of 208 F g-1 and a capacitance retention of >99% after 2000 cycles. The reported strategy is an important step forward toward the development of environmentally friendly TrGO for future electrical or electrochemical applications.
Collapse
Affiliation(s)
- Cataldo Valentini
- Université de Strasbourg and CNRS, ISIS, 8 allée Gaspard Monge, 67000 Strasbourg, France.
| | - Verónica Montes-García
- Université de Strasbourg and CNRS, ISIS, 8 allée Gaspard Monge, 67000 Strasbourg, France.
| | - Pietro Antonio Livio
- Université de Strasbourg and CNRS, ISIS, 8 allée Gaspard Monge, 67000 Strasbourg, France.
| | - Tomasz Chudziak
- Centre for Advanced Technologies, Adam Mickiewicz University, Uniwersytetu Poznańskiego 10, 61-614 Poznań, Poland
- Faculty of Chemistry, Adam Mickiewicz University, Uniwersytetu Poznańskiego 8, 61-614 Poznań, Poland
| | - Jésus Raya
- Université de Strasbourg, CNRS, Membrane Biophysics and NMR, Institute of Chemistry, 1 Rue Blaise Pascal, 67000 Strasbourg, France
| | - Artur Ciesielski
- Université de Strasbourg and CNRS, ISIS, 8 allée Gaspard Monge, 67000 Strasbourg, France.
- Centre for Advanced Technologies, Adam Mickiewicz University, Uniwersytetu Poznańskiego 10, 61-614 Poznań, Poland
| | - Paolo Samorì
- Université de Strasbourg and CNRS, ISIS, 8 allée Gaspard Monge, 67000 Strasbourg, France.
| |
Collapse
|
3
|
Klimavicius V, Maršalka A, Kizalaite A, Zarkov A, Kareiva A, Aidas K, Hirschinger J, Balevicius V. Step-by-step from amorphous phosphate to nano-structured calcium hydroxyapatite: monitoring by solid-state 1H and 31P NMR and spin dynamics. Phys Chem Chem Phys 2022; 24:18952-18965. [PMID: 35916288 DOI: 10.1039/d2cp02108k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The solid-state 1H, 31P NMR spectra and cross-polarization (CP MAS) kinetics in the series of samples containing amorphous phosphate phase (AMP), composite of AMP + nano-structured calcium hydroxyapatite (nano-CaHA) and high-crystalline nano-CaHA were studied under moderate spinning rates (5-30 kHz). The combined analysis of the solid-state 1H and 31P NMR spectra provides the possibility to determine the hydration numbers of the components and the phase composition index. A broad set of spin dynamics models (isotropic/anisotropic, relaxing/non-relaxing, secular/semi-non-secular) was applied and fitted to the experimental CP MAS data. The anisotropic model with the angular averaging of dipolar coupling was applied for AMP and nano-CaHA for the first time. It was deduced that the spin diffusion in AMP is close to isotropic, whereas it is highly anisotropic in nano-CaHA being close to the Ising-type. This can be caused by the different number of internuclear interactions that must be explicitly considered in the spin system for AMP (I-S spin pair) and nano-CaHA (IN-S spin system with N ≥ 2). The P-H distance in nano-CaHA was found to be significantly shorter than its crystallographic value. An underestimation can be caused by several factors, among those - proton conductivity via a large-amplitude motion of protons (O-H tumbling and the short-range diffusion) that occurs along OH- chains. The P-H distance deduced for AMP, i.e. the compound with HPO42- as the dominant structure, is fairly well matched to the crystallographic data. This means that the CP MAS kinetics is a capable technique to obtain complementary information on the proton localization in H-bonds and the proton transfer in the cases where traditional structure determination methods fail.
Collapse
Affiliation(s)
| | - Arūnas Maršalka
- Institute of Chemical Physics, Vilnius University, LT-10257 Vilnius, Lithuania.
| | - Agne Kizalaite
- Institute of Chemistry, Vilnius University, LT-03225, Vilnius, Lithuania
| | - Aleksej Zarkov
- Institute of Chemistry, Vilnius University, LT-03225, Vilnius, Lithuania
| | - Aivaras Kareiva
- Institute of Chemistry, Vilnius University, LT-03225, Vilnius, Lithuania
| | - Kęstutis Aidas
- Institute of Chemical Physics, Vilnius University, LT-10257 Vilnius, Lithuania.
| | - Jérôme Hirschinger
- Institut de Chimie, Université de Strasbourg, UMR 7177 CNRS, Strasbourg, France
| | - Vytautas Balevicius
- Institute of Chemical Physics, Vilnius University, LT-10257 Vilnius, Lithuania.
| |
Collapse
|
4
|
Mauel A, Pötzschner B, Meides N, Siegel R, Strohriegl P, Senker J. Quantification of photooxidative defects in weathered microplastics using 13C multiCP NMR spectroscopy. RSC Adv 2022; 12:10875-10885. [PMID: 35425044 PMCID: PMC8988274 DOI: 10.1039/d2ra00470d] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2022] [Accepted: 03/29/2022] [Indexed: 11/21/2022] Open
Abstract
Weathering of microplastics made of commodity plastics like polystyrene, polypropylene and polyethylene introduces polar polymer defects as a result of photooxidation and mechanical stress. Thus, hydrophobic microplastic particles gradually become hydrophilic, consisting of polar oligomers with a significant amount of oxygen-bearing functional groups. This turnover continuously changes interactions between microplastics and natural colloidal matter. To be able to develop a better understanding of this complex weathering process, quantification of the corresponding defect proportions is a first and essential step. Using polystyrene, 13C enriched at the α position to 23%, we demonstrate that 13C cross polarisation (CP) NMR spectroscopy allows for probing the typical alcohol, peroxo, keto and carboxyl defects. Even the discrimination between in- and end-chain ketones, carboxylic acids and esters as well as ketal functions was possible. Combined with multiCP excitation, defect proportions could be determined with excellent accuracy down to 0.1%. For materials with 13C in natural abundance, this accounts for a detection limit of roughly 1%. The best trade-off between measurement time and accuracy for the quantification of the defect intensities for multiCP excitation was obtained for CP block lengths shorter than 250 μs and total build-up times longer than 2 ms. Further measurement time reduction is possible by using multiCP excitation to calibrate intensities obtained from series of 13C CP MAS NMR spectra. As photooxidation is an important degradation mechanism for microplastics in the environment, we expect these parameters to be transferable for probing defect proportions of weathered microplastics in general. We demonstrate an efficient strategy to characterise weathering-induced photooxidative defects in microplastics. The central 13C cross polarisation NMR spectra offer high resolution and are quantitative when combined with multiple excitation.![]()
Collapse
Affiliation(s)
- Anika Mauel
- Department of Inorganic Chemistry III, University of Bayreuth, Universitätsstraße 30 95447 Bayreuth Germany
| | - Björn Pötzschner
- Department of Inorganic Chemistry III, University of Bayreuth, Universitätsstraße 30 95447 Bayreuth Germany
| | - Nora Meides
- Department of Macromolecular Chemistry I, University of Bayreuth, Universitätsstraße 30 95447 Bayreuth Germany
| | - Renée Siegel
- Department of Inorganic Chemistry III, University of Bayreuth, Universitätsstraße 30 95447 Bayreuth Germany
| | - Peter Strohriegl
- Department of Macromolecular Chemistry I, University of Bayreuth, Universitätsstraße 30 95447 Bayreuth Germany
| | - Jürgen Senker
- Department of Inorganic Chemistry III, University of Bayreuth, Universitätsstraße 30 95447 Bayreuth Germany
| |
Collapse
|
5
|
Klimavicius V, Dagys L, Klimkevičius V, Lengvinaitė D, Aidas K, Balčiu Nas S, Banys J, Chizhik V, Balevicius V. Solid-State NMR and Impedance Spectroscopy Study of Spin Dynamics in Proton-Conducting Polymers: An Application of Anisotropic Relaxing Model. J Phys Chem B 2021; 125:12592-12602. [PMID: 34748346 PMCID: PMC8607415 DOI: 10.1021/acs.jpcb.1c06533] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
![]()
The 1H–13C cross-polarization (CP)
kinetics in poly[2-(methacryloyloxy)ethyltrimethylammonium chloride]
(PMETAC) was studied under moderate (10 kHz) magic-angle spinning
(MAS). To elucidate the role of adsorbed water in spin diffusion and
proton conductivity, PMETAC was degassed under vacuum. The CP MAS
results were processed by applying the anisotropic Naito and McDowell
spin dynamics model, which includes the complete scheme of the rotating
frame spin–lattice relaxation pathways. Some earlier studied
proton-conducting and nonconducting polymers were added to the analysis
in order to prove the capability of the used approach and to get more
general conclusions. The spin-diffusion rate constant, which describes
the damping of the coherences, was found to be strongly depending
on the dipolar I–S coupling constant (DIS). The spin diffusion, associated with the incoherent thermal
equilibration with the bath, was found to be most probably independent
of DIS. It was deduced that the drying
scarcely influences the spin-diffusion rates; however, it significantly
(1 order of magnitude) reduces the rotating frame spin–lattice
relaxation times. The drying causes the polymer hardening that reflects
the changes of the local order parameters. The impedance spectroscopy
was applied to study proton conductivity. The activation energies
for dielectric relaxation and proton conductivity were determined,
and the vehicle-type conductivity mechanism was accepted. The spin-diffusion
processes occur on the microsecond scale and are one order faster
than the dielectric relaxation. The possibility to determine the proton
location in the H-bonded structures in powders using CP MAS technique
is discussed.
Collapse
Affiliation(s)
| | - Laurynas Dagys
- Department of Chemistry, University of Southampton, SO17 1BJ Southampton, U.K
| | | | - Dovilė Lengvinaitė
- Institute of Chemical Physics, Vilnius University, LT-10257 Vilnius, Lithuania
| | - Kęstutis Aidas
- Institute of Chemical Physics, Vilnius University, LT-10257 Vilnius, Lithuania
| | - Sergejus Balčiu Nas
- Institute of Applied Electrodynamics and Telecommunications, Vilnius University, LT-10257 Vilnius, Lithuania
| | - Juras Banys
- Institute of Applied Electrodynamics and Telecommunications, Vilnius University, LT-10257 Vilnius, Lithuania
| | - Vladimir Chizhik
- Faculty of Physics, St. Petersburg State University, 198504 St. Petersburg, Russia
| | - Vytautas Balevicius
- Institute of Chemical Physics, Vilnius University, LT-10257 Vilnius, Lithuania
| |
Collapse
|
6
|
Dagys L, Klimkevičius V, Klimavicius V, Balčiūnas S, Banys J, Balevicius V. Cross‐polarization with magic‐angle spinning kinetics and impedance spectroscopy study of proton mobility, local disorder, and thermal equilibration in
hydrogen‐bonded
poly(methacrylic acid). JOURNAL OF POLYMER SCIENCE 2020. [DOI: 10.1002/pol.20200592] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- Laurynas Dagys
- Institute of Chemical Physics Vilnius University Vilnius Lithuania
- Department of Chemistry University of Southampton Southampton UK
| | | | - Vytautas Klimavicius
- Institute of Chemical Physics Vilnius University Vilnius Lithuania
- Eduard‐Zintl Institute for Inorganic and Physical Chemistry University of Technology Darmstadt Darmstadt Germany
| | - Sergejus Balčiūnas
- Institute of Applied Electrodynamics and Telecommunications Vilnius University Vilnius Lithuania
| | - Jūras Banys
- Institute of Applied Electrodynamics and Telecommunications Vilnius University Vilnius Lithuania
| | | |
Collapse
|