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Shen D, Zhou Z, Xu Y, Shao C, Shi Y, Zhao W, Tang R, Pan H, Yu M, Hannig M, Fu B. Reversion of ACP Nanoparticles into Prenucleation Clusters via Surfactant for Promoting Biomimetic Mineralization: A Physicochemical Understanding of Biosurfactant Role in Biomineralization Process. Adv Healthc Mater 2024; 13:e2303488. [PMID: 38265149 DOI: 10.1002/adhm.202303488] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2023] [Revised: 11/21/2023] [Indexed: 01/25/2024]
Abstract
Amphiphilic biomolecules are abundant in mineralization front of biological hard tissues, which play a vital role in osteogenesis and dental hard tissue formation. Amphiphilic biomolecules function as biosurfactants, however, their biosurfactant role in biomineralization process has never been investigated. This study, for the first time, demonstrates that aggregated amorphous calcium phosphate (ACP) nanoparticles can be reversed into dispersed ultrasmall prenucleation clusters (PNCs) via breakdown and dispersion of the ACP nanoparticles by a surfactant. The reduced surface energy of ACP@TPGS and the electrostatic interaction between calcium ions and the pair electrons on oxygen atoms of C-O-C of D-α-tocopheryl polyethylene glycol succinate (TPGS) provide driving force for breakdown and dispersion of ACP nanoparticles into ultrasmall PNCs which promote in vitro and in vivo biomimetic mineralization. The ACP@TPGS possesses excellent biocompatibility without any irritations to oral mucosa and dental pulp. This study not only introduces surfactant into biomimetic mineralization field, but also excites attention to the neglected biosurfactant role during biomineralization process.
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Affiliation(s)
- Dongni Shen
- Stomatology Hospital, School of Stomatology, Zhejiang University School of Medicine, Zhejiang Provincial Clinical Research Center for Oral Diseases, Key Laboratory of Oral Biomedical Research of Zhejiang Province, Cancer Center of Zhejiang University, Engineering Research Center of Oral Biomaterials and Devices of Zhejiang Province, Hangzhou, Zhejiang, 310000, China
| | - Zihuai Zhou
- Stomatology Hospital, School of Stomatology, Zhejiang University School of Medicine, Zhejiang Provincial Clinical Research Center for Oral Diseases, Key Laboratory of Oral Biomedical Research of Zhejiang Province, Cancer Center of Zhejiang University, Engineering Research Center of Oral Biomaterials and Devices of Zhejiang Province, Hangzhou, Zhejiang, 310000, China
| | - Yuedan Xu
- Stomatology Hospital, School of Stomatology, Zhejiang University School of Medicine, Zhejiang Provincial Clinical Research Center for Oral Diseases, Key Laboratory of Oral Biomedical Research of Zhejiang Province, Cancer Center of Zhejiang University, Engineering Research Center of Oral Biomaterials and Devices of Zhejiang Province, Hangzhou, Zhejiang, 310000, China
| | - Changyu Shao
- Stomatology Hospital, School of Stomatology, Zhejiang University School of Medicine, Zhejiang Provincial Clinical Research Center for Oral Diseases, Key Laboratory of Oral Biomedical Research of Zhejiang Province, Cancer Center of Zhejiang University, Engineering Research Center of Oral Biomaterials and Devices of Zhejiang Province, Hangzhou, Zhejiang, 310000, China
| | - Ying Shi
- Stomatology Hospital, School of Stomatology, Zhejiang University School of Medicine, Zhejiang Provincial Clinical Research Center for Oral Diseases, Key Laboratory of Oral Biomedical Research of Zhejiang Province, Cancer Center of Zhejiang University, Engineering Research Center of Oral Biomaterials and Devices of Zhejiang Province, Hangzhou, Zhejiang, 310000, China
| | - Weijia Zhao
- Stomatology Hospital, School of Stomatology, Zhejiang University School of Medicine, Zhejiang Provincial Clinical Research Center for Oral Diseases, Key Laboratory of Oral Biomedical Research of Zhejiang Province, Cancer Center of Zhejiang University, Engineering Research Center of Oral Biomaterials and Devices of Zhejiang Province, Hangzhou, Zhejiang, 310000, China
| | - Ruikang Tang
- Center for Biomaterials and Biopathways, Department of Chemistry, Zhejiang University, Hangzhou, Zhejiang Province, 310000, China
| | - Haihua Pan
- Qiushi Academy for Advanced Studies, Zhejiang University, Hangzhou, Zhejiang Province, 310000, China
| | - Mengfei Yu
- Stomatology Hospital, School of Stomatology, Zhejiang University School of Medicine, Zhejiang Provincial Clinical Research Center for Oral Diseases, Key Laboratory of Oral Biomedical Research of Zhejiang Province, Cancer Center of Zhejiang University, Engineering Research Center of Oral Biomaterials and Devices of Zhejiang Province, Hangzhou, Zhejiang, 310000, China
| | - Matthias Hannig
- Clinic of Operative Dentistry, Periodontology and Preventive Dentistry, Saarland University, 66424, Homburg, Saarland, Germany
| | - Baiping Fu
- Stomatology Hospital, School of Stomatology, Zhejiang University School of Medicine, Zhejiang Provincial Clinical Research Center for Oral Diseases, Key Laboratory of Oral Biomedical Research of Zhejiang Province, Cancer Center of Zhejiang University, Engineering Research Center of Oral Biomaterials and Devices of Zhejiang Province, Hangzhou, Zhejiang, 310000, China
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2
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Seredin P, Goloshchapov D, Buylov N, Kashkarov V, Shikhaliev K, Potapov A, Ippolitov Y, Kartsev V, Kuyumchyan S, de Oliveira Freitas R. A Study of the Peculiarities of the Formation of a Hybrid Interface Based on Polydopamine between Dental Tissues and Dental Composites, Using IR and Raman Microspectroscopy, at the Submicron Level. Int J Mol Sci 2023; 24:11636. [PMID: 37511394 PMCID: PMC10380397 DOI: 10.3390/ijms241411636] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2023] [Revised: 07/14/2023] [Accepted: 07/17/2023] [Indexed: 07/30/2023] Open
Abstract
The creation of buffer (hybrid) layers that provide improved adhesion to two heterogeneous materials is a promising and high-priority research area in the field of dental materials science. In our work, using FTIR and Raman microspectroscopy at the submicron level in a system of dental composites/intact dental enamel, we assessed the molecular features of formation and chemically visualized the hybrid interface formed on the basis of a nature-like adhesive, polydopamine (PDA). It is shown that a homogeneous bioinspired PDA-hybrid interface with an increased content of O-Ca-O bonds can be created using traditional methods of dental tissue pretreatment (diamond micro drilling, acid etching), as well as the subsequent alkalinization procedure and the developed synthesis technology. The development of the proposed technology for accelerated deposition of PDA-hybrid layers, as well as the creation of self-assembled biomimetic nanocomposites with antibacterial properties, may in the future find clinical application for minimally invasive dental restoration procedures.
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Affiliation(s)
- Pavel Seredin
- Solid State Physics and Nanostructures Department, Voronezh State University, University Sq. 1, 394018 Voronezh, Russia
| | - Dmitry Goloshchapov
- Solid State Physics and Nanostructures Department, Voronezh State University, University Sq. 1, 394018 Voronezh, Russia
| | - Nikita Buylov
- Solid State Physics and Nanostructures Department, Voronezh State University, University Sq. 1, 394018 Voronezh, Russia
| | - Vladimir Kashkarov
- Solid State Physics and Nanostructures Department, Voronezh State University, University Sq. 1, 394018 Voronezh, Russia
| | - Khidmet Shikhaliev
- Laboratory of Organic Additives for the Processes of Chemical and Electrochemical Deposition of Metals and Alloys Used in the Electronics Industry, Voronezh State University, University Sq. 1, 394018 Voronezh, Russia
| | - Andrey Potapov
- Laboratory of Organic Additives for the Processes of Chemical and Electrochemical Deposition of Metals and Alloys Used in the Electronics Industry, Voronezh State University, University Sq. 1, 394018 Voronezh, Russia
| | - Yuri Ippolitov
- Department of Pediatric Dentistry with Orthodontia, Voronezh State Medical University, Studentcheskaya St. 11, 394006 Voronezh, Russia
| | | | - Sergey Kuyumchyan
- Saint Petersburg State University Hospital, 154, Fontanka River Embankment, 198103 St. Petersburg, Russia
| | - Raul de Oliveira Freitas
- Brazilian Synchrotron Light Laboratory (LNLS), Brazilian Center for Research in Energy and Materials (CNPEM), Campinas 13083-970, Sao Paulo, Brazil
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3
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Agarwal S, Aiello CD, Kattnig DR, Banerjee AS. The Dynamical Ensemble of the Posner Molecule Is Not Symmetric. J Phys Chem Lett 2021; 12:10372-10379. [PMID: 34668712 DOI: 10.1021/acs.jpclett.1c02796] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
The Posner molecule, Ca9(PO4)6, has long been recognized to have biochemical relevance in various physiological processes. It has found recent attention for its possible role as a biological quantum information processor, whereby the molecule purportedly maintains long-lived nuclear spin coherences among its 31P nuclei (presumed to be symmetrically arranged), allowing it to function as a room temperature qubit. The structure of the molecule has been of much dispute in the literature, although the S6 point group symmetry has often been assumed and exploited in calculations. Using a variety of simulation techniques (including ab initio molecular dynamics and structural relaxation), rigorous data analysis tools, and by exploring thousands of individual configurations, we establish that the molecule predominantly assumes low-symmetry structures (Cs and Ci) at room temperature, as opposed to the higher-symmetry configurations explored previously. Our findings have important implications for the viability of this molecule as a qubit.
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Affiliation(s)
- Shivang Agarwal
- Department of Electrical and Computer Engineering, University of California, Los Angeles 90095, United States
| | - Clarice D Aiello
- Department of Electrical and Computer Engineering, University of California, Los Angeles 90095, United States
| | - Daniel R Kattnig
- Department of Physics and Living Systems Institute, University of Exeter, Exeter EX4 4QD, U.K
| | - Amartya S Banerjee
- Department of Materials Science and Engineering, University of California, Los Angeles 90095, United States
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4
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Millán Á, Lanzer P, Sorribas V. The Thermodynamics of Medial Vascular Calcification. Front Cell Dev Biol 2021; 9:633465. [PMID: 33937234 PMCID: PMC8080379 DOI: 10.3389/fcell.2021.633465] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Accepted: 03/18/2021] [Indexed: 12/14/2022] Open
Abstract
Medial vascular calcification (MVC) is a degenerative process that involves the deposition of calcium in the arteries, with a high prevalence in chronic kidney disease (CKD), diabetes, and aging. Calcification is the process of precipitation largely of calcium phosphate, governed by the laws of thermodynamics that should be acknowledged in studies of this disease. Amorphous calcium phosphate (ACP) is the key constituent of early calcifications, mainly composed of Ca2+ and PO4 3- ions, which over time transform into hydroxyapatite (HAP) crystals. The supersaturation of ACP related to Ca2+ and PO4 3- activities establishes the risk of MVC, which can be modulated by the presence of promoter and inhibitor biomolecules. According to the thermodynamic parameters, the process of MVC implies: (i) an increase in Ca2+ and PO4 3- activities (rather than concentrations) exceeding the solubility product at the precipitating sites in the media; (ii) focally impaired equilibrium between promoter and inhibitor biomolecules; and (iii) the progression of HAP crystallization associated with nominal irreversibility of the process, even when the levels of Ca2+ and PO4 3- ions return to normal. Thus, physical-chemical processes in the media are fundamental to understanding MVC and represent the most critical factor for treatments' considerations. Any pathogenetical proposal must therefore comply with the laws of thermodynamics and their expression within the medial layer.
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Affiliation(s)
- Ángel Millán
- Instituto de Nanociencia y Materiales de Aragón (INMA), CSIC-Universidad de Zaragoza, Zaragoza, Spain
| | - Peter Lanzer
- Division of Cardiovascular Disease, Department of Internal Medicine, Health Care Center Bitterfeld, Bitterfeld-Wolfen gGmbH, Bitterfeld-Wolfen, Germany
| | - Víctor Sorribas
- Molecular Toxicology Group, Department of Biochemistry and Molecular and Cell Biology, University of Zaragoza, Zaragoza, Spain
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5
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Cruz MAE, Ferreira CR, Tovani CB, de Oliveira FA, Bolean M, Caseli L, Mebarek S, Millán JL, Buchet R, Bottini M, Ciancaglini P, Paula Ramos A. Phosphatidylserine controls calcium phosphate nucleation and growth on lipid monolayers: A physicochemical understanding of matrix vesicle-driven biomineralization. J Struct Biol 2020; 212:107607. [PMID: 32858148 DOI: 10.1016/j.jsb.2020.107607] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Revised: 08/15/2020] [Accepted: 08/19/2020] [Indexed: 12/12/2022]
Abstract
Bone biomineralization is an exquisite process by which a hierarchically organized mineral matrix is formed. Growing evidence has uncovered the involvement of one class of extracellular vesicles, named matrix vesicles (MVs), in the formation and delivery of the first mineral nuclei to direct collagen mineralization. MVs are released by mineralization-competent cells equipped with a specific biochemical machinery to initiate mineral formation. However, little is known about the mechanisms by which MVs can trigger this process. Here, we present a combination of in situ investigations and ex vivo analysis of MVs extracted from growing-femurs of chicken embryos to investigate the role played by phosphatidylserine (PS) in the formation of mineral nuclei. By using self-assembled Langmuir monolayers, we reconstructed the nucleation core - a PS-enriched motif thought to trigger mineral formation in the lumen of MVs. In situ infrared spectroscopy of Langmuir monolayers and ex situ analysis by transmission electron microscopy evidenced that mineralization was achieved in supersaturated solutions only when PS was present. PS nucleated amorphous calcium phosphate that converted into biomimetic apatite. By using monolayers containing lipids extracted from native MVs, mineral formation was also evidenced in a manner that resembles the artificial PS-enriched monolayers. PS-enrichment in lipid monolayers creates nanodomains for local increase of supersaturation, leading to the nucleation of ACP at the interface through a multistep process. We posited that PS-mediated nucleation could be a predominant mechanism to produce the very first mineral nuclei during MV-driven bone/cartilage biomineralization.
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Affiliation(s)
- Marcos A E Cruz
- Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, FFCLRP - Universidade de São Paulo - Departamento de Química, Brazil
| | - Claudio R Ferreira
- Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, FFCLRP - Universidade de São Paulo - Departamento de Química, Brazil
| | - Camila B Tovani
- Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, FFCLRP - Universidade de São Paulo - Departamento de Química, Brazil
| | | | - Maytê Bolean
- Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, FFCLRP - Universidade de São Paulo - Departamento de Química, Brazil
| | - Luciano Caseli
- Institute of Environmental, Chemical and Pharmaceutical Sciences - Federal University of Sao Paulo, Brazil
| | - Saida Mebarek
- Universite de Lyon, ICBMS UMR 5246 CNRS, Villeurbanne, France
| | - José Luis Millán
- Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037, USA
| | - Rene Buchet
- Universite de Lyon, ICBMS UMR 5246 CNRS, Villeurbanne, France
| | - Massimo Bottini
- Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037, USA; Department of Experimental Medicine, University of Rome Tor Vergata, 00133 Rome, Italy
| | - Pietro Ciancaglini
- Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, FFCLRP - Universidade de São Paulo - Departamento de Química, Brazil.
| | - Ana Paula Ramos
- Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, FFCLRP - Universidade de São Paulo - Departamento de Química, Brazil.
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7
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Gebauer D, Wolf SE. Designing Solid Materials from Their Solute State: A Shift in Paradigms toward a Holistic Approach in Functional Materials Chemistry. J Am Chem Soc 2019; 141:4490-4504. [DOI: 10.1021/jacs.8b13231] [Citation(s) in RCA: 87] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Affiliation(s)
- Denis Gebauer
- Department of Chemistry, Physical Chemistry, University of Konstanz, 78457 Konstanz, Germany
| | - Stephan E. Wolf
- Department of Materials Science and Engineering, Institute of Glass and Ceramics and Interdisciplinary Center for Functional Particle Systems, Friedrich-Alexander-University Erlangen-Nuremberg, 91058 Erlangen, Germany
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8
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Yang X, Wang M, Yang Y, Cui B, Xu Z, Yang X. Physical origin underlying the prenucleation-cluster-mediated nonclassical nucleation pathways for calcium phosphate. Phys Chem Chem Phys 2019; 21:14530-14540. [PMID: 30984939 DOI: 10.1039/c9cp00919a] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The involvement of prenucleation clusters (PNCs) in crystallization from a supersaturated solution has been recently admitted within the framework of nonclassical nucleation theory; however, little is known about PNCs, at the quantitative level, for their formation mechanism and stability, the new phase formed by them, as well as their impact on nucleation barriers. Herein, using the sophisticated free energy calculations with a cumulative simulation time of over 5 μs, we identify a thermodynamically favored pathway of the PNC-mediated nucleation for calcium phosphate, starting with the ion pair association in solution. We demonstrate that such an ion association occurs not only between cations and anions, but also for the polyatomic species with charges of the same sign, which, in fact, leads to PNC formation via the consecutive coordination of the phosphate ions to calcium. The free energy decomposition calculations illustrate that the water phase is capable to either hinder or promote ion association for the abovementioned processes, and its specific role is intricately related to the characteristics of the hydration shell around calcium ions. The favorable interactions between the highly charged species play a crucial role in stabilizing the PNC complexes and the aggregates formed by PNCs. Furthermore, our present work reveals that the uptake of an extra calcium ion is the first and mandatory step to trigger PNC aggregation into amorphous calcium phosphate (ACP) by eliminating the related free energy barriers. Our theoretical study successfully provides quantitative explanations to a large set of experimental data in the field, which is currently under intense discussions associated with the nonclassical nucleation mechanism. The combination of computational methods developed in our present work offers a feasible and general solution to quantitatively and systematically study ion associations and crystal nucleation/growth in an aqueous solution at the atomic level, which are normally inaccessible to most of the existing experimental acquisitions.
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Affiliation(s)
- Xiao Yang
- College of Chemical Engineering, State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing 210009, China.
| | - Mingzhu Wang
- College of Chemical Engineering, State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing 210009, China.
| | - Yang Yang
- Department of Chemistry, Lehigh University, 6 East Packer Avenue, Bethlehem, PA 18015, USA
| | - Beiliang Cui
- Network Information Center, Nanjing Tech University, Nanjing 210009, China
| | - Zhijun Xu
- College of Chemical Engineering, State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing 210009, China.
| | - Xiaoning Yang
- College of Chemical Engineering, State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing 210009, China.
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9
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Innocenti Malini R, L. Freeman C, Harding JH. Interaction of stable aggregates drives the precipitation of calcium phosphate in supersaturated solutions. CrystEngComm 2019. [DOI: 10.1039/c9ce00658c] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Using molecular dynamics simulations, we show for the first time that calcium phosphate nanoparticles of eight formula units are thermodynamically stable and could be key in the nucleation of amorphous calcium phosphate.
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Affiliation(s)
- R. Innocenti Malini
- Empa
- Swiss Federal Laboratories for Materials Science and Technology
- Laboratory for Biomimetic Membranes and Textiles
- St. Gallen 9014
- Switzerland
| | - C. L. Freeman
- Department of Materials Science and Engineering
- University of Sheffield
- Sheffield
- UK
| | - J. H. Harding
- Department of Materials Science and Engineering
- University of Sheffield
- Sheffield
- UK
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10
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Fan HX, Gou BD, Gao YX, Wu G, Zhang TL. Pseudo-equilibrium equation of calcium phosphate precipitation from aqueous solution. Phys Chem Chem Phys 2019; 21:22057-22066. [DOI: 10.1039/c9cp04250d] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
For a precipitation reaction involving an amorphous phase, the equilibrium equation takes the general form (middle), which converts to the conventional “reaction quotient” (left) and the “solubility product” (right) in two limit cases, respectively.
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Affiliation(s)
- Hong-Xing Fan
- State Environmental Protection Engineering Center for Mercury Pollution Prevention and Control
- Beijing Synchrotron Radiation Facility
- Institute of High Energy Physics
- Chinese Academy of Sciences
- Beijing 100049
| | - Bao-Di Gou
- Department of Chemical Biology
- Peking University School of Pharmaceutical Sciences
- Beijing 100191
- P. R. China
| | - Yu-Xi Gao
- State Environmental Protection Engineering Center for Mercury Pollution Prevention and Control
- Beijing Synchrotron Radiation Facility
- Institute of High Energy Physics
- Chinese Academy of Sciences
- Beijing 100049
| | - Gang Wu
- Department of Biochemistry
- Baotou Medical College
- Inner Mongolia University of Science & Technology
- Baotou 014010
- P. R. China
| | - Tian-Lan Zhang
- Department of Chemical Biology
- Peking University School of Pharmaceutical Sciences
- Beijing 100191
- P. R. China
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11
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Player TC, Hore PJ. Posner qubits: spin dynamics of entangled Ca 9(PO 4) 6 molecules and their role in neural processing. J R Soc Interface 2018; 15:20180494. [PMID: 30381344 PMCID: PMC6228494 DOI: 10.1098/rsif.2018.0494] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2018] [Accepted: 10/08/2018] [Indexed: 11/12/2022] Open
Abstract
It has been suggested that 31P nuclear spins in Ca9(PO4)6 molecules could form the basis of a quantum mechanism for neural processing in the brain. A fundamental requirement of this proposal is that spins in different Ca9(PO4)6 molecules can become entangled and remain so for periods (estimated at many hours) that hugely exceed typical 31P spin relaxation times. Here, we consider the coherent and incoherent spin dynamics of Ca9(PO4)6 arising from dipolar and scalar spin-spin interactions and derive an upper bound of 37 min on the entanglement lifetime under idealized physiological conditions. We argue that the spin relaxation in Ca9(PO4)6 is likely to be much faster than this estimate.
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Affiliation(s)
- Thomas C Player
- Department of Chemistry, University of Oxford, Oxford OX1 3QZ, UK
| | - P J Hore
- Department of Chemistry, University of Oxford, Oxford OX1 3QZ, UK
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12
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Swift MW, Van de Walle CG, Fisher MPA. Posner molecules: from atomic structure to nuclear spins. Phys Chem Chem Phys 2018; 20:12373-12380. [DOI: 10.1039/c7cp07720c] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The Posner molecule, Ca9(PO4)6, a possible intermediate step in bone growth, may also protect the constituent 31P spins from decoherence.
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