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Higaki Y, Masuda T, Shiomoto S, Tanaka Y, Kiuchi H, Harada Y, Tanaka M. Pronounced Cold Crystallization and Hydrogen Bonding Distortion of Water Confined in Microphases of Double Zwitterionic Block Copolymer Aqueous Solutions. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2024; 40:19612-19618. [PMID: 39227353 DOI: 10.1021/acs.langmuir.4c02254] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/05/2024]
Abstract
Advanced materials leveraging water control are garnering considerable interest, with the state of water emerging as a critical aspect of material design. This study explored the impact of microphase separation on water using aqueous solutions of double zwitterionic diblock copolymers, specifically poly(carboxybetaine methacrylate) and poly(sulfobetaine methacrylate) (PCB2-b-PSB4). These copolymers form a mesoscale periodic ordered lattice structure consisting of two distinct aqueous phases. Through differential scanning calorimetry and X-ray emission spectroscopy, it was found that water in these PCB2-b-PSB4 aqueous solutions exhibits pronounced cold crystallization and subtle distortions in hydrogen-bonding configurations.
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Affiliation(s)
- Yuji Higaki
- Faculty of Science and Technology, Oita University, 700 Dannoharu, Oita 870-1192, Japan
| | - Takumi Masuda
- Graduate School of Engineering, Oita University, 700 Dannoharu, Oita 870-1192, Japan
| | - Shohei Shiomoto
- Institute for Materials Chemistry and Engineering, Kyushu University, Fukuoka 819-0395, Japan
| | - Yukiko Tanaka
- Institute for Materials Chemistry and Engineering, Kyushu University, Fukuoka 819-0395, Japan
| | - Hisao Kiuchi
- Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581, Japan
- Synchrotron Radiation Research Organization, The University of Tokyo, Sayo-gun, Hyogo 679-5148, Japan
| | - Yoshihisa Harada
- Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581, Japan
- Synchrotron Radiation Research Organization, The University of Tokyo, Sayo-gun, Hyogo 679-5148, Japan
| | - Masaru Tanaka
- Institute for Materials Chemistry and Engineering, Kyushu University, Fukuoka 819-0395, Japan
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Mochizuki A, Udagawa A, Miwa Y, Oda Y, Yoneyama K, Okuda C. Blood compatibility of poly(propylene glycol diester) and its water structure observed by differential scanning calorimetry and 2H-nuclear magnetic resonance spectroscopy. JOURNAL OF BIOMATERIALS SCIENCE. POLYMER EDITION 2024; 35:1258-1272. [PMID: 38457333 DOI: 10.1080/09205063.2024.2324505] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2023] [Accepted: 11/17/2023] [Indexed: 03/10/2024]
Abstract
Recently, we applied solution 2H-nuclear magnetic resonance spectroscopy (2H NMR) to analyze the water (deuterium oxide, D2O) structure in several biopolymers at ambient temperature. We established that polymers with good blood compatibility (i.e. poly(2-methoxyethyl acrylate) (PMEA)) have water observed at high magnetic fields (upfield) compared with bulk water. Polymers containing poly(propylene glycol) (PPG) or poly(propylene oxide) (PPO) exhibit good compatibility; however, the reason for this remains unclear. In addition, reports on the blood compatibility of PPO/PPG are limited. Therefore, PPG diester (PPGest) was prepared as a model polymer, and its blood compatibility and water structure were investigated. PPGest exhibited excellent blood compatibility. The water in PPGest was observed upfield by 2H NMR, and it was defined as non-freezing water via differential scanning calorimetry. Based on these observations, the relationship between the blood compatibility and water structure of PPGest is discussed by comparing with those of PMEA, and the reason for the good performance of PPG/PPO-based polymers is discussed.
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Affiliation(s)
- Akira Mochizuki
- Department of Bio-Medical Engineering, School of Engineering, Tokai University, Isehara, Japan
| | - Ayaka Udagawa
- Department of Bio-Medical Engineering, School of Engineering, Tokai University, Isehara, Japan
| | | | - Yoshiki Oda
- Technology Joint Management Office of Tokai University, Hiratsuka, Japan
| | - Konatsu Yoneyama
- Department of Bio-Medical Engineering, School of Engineering, Tokai University, Isehara, Japan
| | - Chihiro Okuda
- Department of Bio-Medical Engineering, School of Engineering, Tokai University, Isehara, Japan
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3
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Higuchi Y, Saleh MA, Anada T, Tanaka M, Hishida M. Rotational Dynamics of Water near Osmolytes by Molecular Dynamics Simulations. J Phys Chem B 2024; 128:5008-5017. [PMID: 38728154 DOI: 10.1021/acs.jpcb.3c08470] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/12/2024]
Abstract
The behavior of water molecules around organic molecules has attracted considerable attention as a crucial factor influencing the properties and functions of soft matter and biomolecules. Recently, it has been suggested that the change in protein stability upon the addition of small organic molecules (osmolytes) is dominated by the change in the water dynamics caused by the osmolyte, where the dynamics of not only the directly interacting water molecules but also the long-range hydration layer affect the protein stability. However, the relation between the long-range structure of hydration water in various solutions and the water dynamics remains unclear at the molecular level. We performed density-functional tight-binding molecular dynamics simulations to elucidate the varying rotational dynamics of water molecules in 15 osmolyte solutions. A positive correlation was observed between the rotational relaxation time and our proposed normalized parameter obtained by dividing the number of hydrogen bonds between water molecules by the number of nearest-neighbor water molecules. For the 15 osmolyte solutions, an increase or a decrease in the value of the normalized parameter for the second hydration shell tended to result in water molecules with slow and fast rotational dynamics, respectively, thus illustrating the importance of the second hydration shell for the rotational dynamics of water molecules. Our simulation results are anticipated to advance the current understanding of water dynamics around organic molecules and the long-range structure of water molecules.
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Affiliation(s)
- Yuji Higuchi
- Research Institute for Information Technology, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Md Abu Saleh
- Department of Applied Chemistry, Graduate School of Engineering, Kyushu University, Fukuoka 819-0395, Japan
| | - Takahisa Anada
- Department of Applied Chemistry, Graduate School of Engineering, Kyushu University, Fukuoka 819-0395, Japan
- Institute for Materials Chemistry and Engineering, Kyushu University, Fukuoka 819-0395, Japan
| | - Masaru Tanaka
- Department of Applied Chemistry, Graduate School of Engineering, Kyushu University, Fukuoka 819-0395, Japan
- Institute for Materials Chemistry and Engineering, Kyushu University, Fukuoka 819-0395, Japan
| | - Mafumi Hishida
- Department of Chemistry, Faculty of Science, Tokyo University of Science, 1-3 Kagurazaka, Shinjuku, Tokyo 162-8601, Japan
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Hirayama T, Yamashita N, Yamamoto W, Shirode K, Okada A, Hatano N, Tsuchiya T, Yamada M. Adsorption Characteristics and Mechanical Responses of Lubricants Containing Polymer Additives under Fluid Lubrication with a Narrow Gap. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2024; 40:6229-6243. [PMID: 38483280 DOI: 10.1021/acs.langmuir.3c03725] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/27/2024]
Abstract
The adsorption behavior of poly(methyl acrylate) (PMA)-based polymer additives and their mechanical response under fluid lubrication in narrow gaps were investigated by using neutron reflectometry, microchannel devices, and the narrow gap viscometer. The surface adsorption layer formed by the polymer additive in a stationary field that was investigated by neutron reflectometry was only about 3 nm thick. On the other hand, when the sample oil containing the polymer additive was flowed into the microchannel device with channels about 500 nm deep, the adsorption layer grew over a long period of time and eventually formed a layer that appeared to be more than 100 nm thick. The mechanical response was measured during one-directional rotation with a constant gap length by using the narrow gap viscometer. The results showed that the effective viscosity increased in the low shear rate range. The same behavior was also observed in the reciprocating rotational tests, where the mechanical response showed a distinctive distortion only when the shear rate was low near 0 rpm. The results of the neutron reflectometer, incorporating the narrow gap viscometer, showed no effect of the rotational speed with regard to the structure of the homogeneous layer over a large area. However, the discrepancy between the reflectivity profile and the fitting curve became progressively more pronounced with time, confirming the formation of inhomogeneous structures with time. It is finally suggested that the inhomogeneous structure is due to the formation of local aggregates by PMA molecules, and it acts as flow resistance only in the low shear rate, resulting in an increase in effective viscosity.
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Affiliation(s)
- Tomoko Hirayama
- Department of Mechanical Science and Engineering, Graduate School of Engineering, Kyoto University Katsura, Nishikyo-ku, Kyoto 615-8540, Japan
| | - Naoki Yamashita
- Department of Mechanical Science and Engineering, Graduate School of Engineering, Kyoto University Katsura, Nishikyo-ku, Kyoto 615-8540, Japan
| | - Waka Yamamoto
- Department of Mechanical Science and Engineering, Graduate School of Engineering, Kyoto University Katsura, Nishikyo-ku, Kyoto 615-8540, Japan
| | - Kenta Shirode
- Department of Mechanical Science and Engineering, Graduate School of Engineering, Kyoto University Katsura, Nishikyo-ku, Kyoto 615-8540, Japan
| | - Akira Okada
- Department of Mechanical Science and Engineering, Graduate School of Engineering, Kyoto University Katsura, Nishikyo-ku, Kyoto 615-8540, Japan
| | - Naoya Hatano
- Department of Mechanical Science and Engineering, Graduate School of Engineering, Kyoto University Katsura, Nishikyo-ku, Kyoto 615-8540, Japan
| | - Toshiyuki Tsuchiya
- Department of Micro Engineering, Graduate School of Engineering, Kyoto University Katsura, Nishikyo-ku, Kyoto 615-8540, Japan
| | - Masako Yamada
- Neutron Science Division, Institute of Materials Structure Science, KEK 203-1 Shirakata, Naka-gun, Tokai-mura, Ibaraki 319-1106, Japan
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5
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Kikuchi T, Tominaga T, Murakami D, de Souza NR, Tanaka M, Seto H. Detailed dynamical features of the slow hydration water in the vicinity of poly(ethylene oxide) chains. J Chem Phys 2024; 160:064902. [PMID: 38341782 DOI: 10.1063/5.0185432] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Accepted: 01/09/2024] [Indexed: 02/13/2024] Open
Abstract
Poly(ethylene oxide) (PEO) is a well-known biocompatible polymer and has widely been used for medical applications. Recently, we have investigated the dynamic behavior of hydration water in the vicinity of PEO chains at physiological temperature and shown the presence of slow water with diffusion coefficient one order of magnitude less than that of bulk water. This could be evidence for the intermediate water that is critical for biocompatibility; however, its detailed dynamical features were not established. In this article, we analyze the quasi-elastic neutron scattering from hydration water through mode distribution analysis and present a microscopic picture of hydration water as well as its relation to cold crystallization.
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Affiliation(s)
- T Kikuchi
- Institute of Materials Structure Science, High Energy Accelerator Research Organization, Tsukuba 305-0801, Japan
| | - T Tominaga
- Neutron Science and Technology Center, Comprehensive Research Organization for Science and Society (CROSS), Tokai 319-1106, Japan
| | - D Murakami
- Faculty of Humanity-Oriented Science and Engineering, Kindai University, Iizuka 820-8555, Japan
| | - N R de Souza
- Australian Nuclear Science and Technology Organization, New Illawarra Rd., Lucas Heights, NSW 2234, Australia
| | - M Tanaka
- Institute for Materials Chemistry and Engineering, Kyushu University, Fukuoka 819-0395, Japan
| | - H Seto
- Institute of Materials Structure Science, High Energy Accelerator Research Organization, Tsukuba 305-0801, Japan
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6
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Moon JD, Webber TR, Brown DR, Richardson PM, Casey TM, Segalman RA, Shell MS, Han S. Nanoscale water-polymer interactions tune macroscopic diffusivity of water in aqueous poly(ethylene oxide) solutions. Chem Sci 2024; 15:2495-2508. [PMID: 38362435 PMCID: PMC10866362 DOI: 10.1039/d3sc05377f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2023] [Accepted: 11/30/2023] [Indexed: 02/17/2024] Open
Abstract
The separation and anti-fouling performance of water purification membranes is governed by both macroscopic and molecular-scale water properties near polymer surfaces. However, even for poly(ethylene oxide) (PEO) - ubiquitously used in membrane materials - there is little understanding of whether or how the molecular structure of water near PEO surfaces affects macroscopic water diffusion. Here, we probe both time-averaged bulk and local water dynamics in dilute and concentrated PEO solutions using a unique combination of experimental and simulation tools. Pulsed-Field Gradient NMR and Overhauser Dynamic Nuclear Polarization (ODNP) capture water dynamics across micrometer length scales in sub-seconds to sub-nanometers in tens of picoseconds, respectively. We find that classical models, such as the Stokes-Einstein and Mackie-Meares relations, cannot capture water diffusion across a wide range of PEO concentrations, but that free volume theory can. Our study shows that PEO concentration affects macroscopic water diffusion by enhancing the water structure and altering free volume. ODNP experiments reveal that water diffusivity near PEO is slower than in the bulk in dilute solutions, previously not recognized by macroscopic transport measurements, but the two populations converge above the polymer overlap concentration. Molecular dynamics simulations reveal that the reduction in water diffusivity occurs with enhanced tetrahedral structuring near PEO. Broadly, we find that PEO does not simply behave like a physical obstruction but directly modifies water's structural and dynamic properties. Thus, even in simple PEO solutions, molecular scale structuring and the impact of polymer interfaces is essential to capturing water diffusion, an observation with important implications for water transport through structurally complex membrane materials.
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Affiliation(s)
- Joshua D Moon
- Materials Department, University of California Santa Barbara California 93106 USA
- Department of Chemical Engineering, University of California Santa Barbara California 93106 USA
| | - Thomas R Webber
- Department of Chemical Engineering, University of California Santa Barbara California 93106 USA
| | - Dennis Robinson Brown
- Department of Chemical Engineering, University of California Santa Barbara California 93106 USA
| | - Peter M Richardson
- Materials Department, University of California Santa Barbara California 93106 USA
| | - Thomas M Casey
- Department of Chemistry and Biochemistry, University of California Santa Barbara California 93106 USA
| | - Rachel A Segalman
- Materials Department, University of California Santa Barbara California 93106 USA
- Department of Chemical Engineering, University of California Santa Barbara California 93106 USA
| | - M Scott Shell
- Department of Chemical Engineering, University of California Santa Barbara California 93106 USA
| | - Songi Han
- Department of Chemical Engineering, University of California Santa Barbara California 93106 USA
- Department of Chemistry and Biochemistry, University of California Santa Barbara California 93106 USA
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Hishida M. Correlation between Hydration States and Self-assembly Structures of Phospholipid and Surfactant Studied by Terahertz Spectroscopy. J Oleo Sci 2024; 73:419-427. [PMID: 38556277 DOI: 10.5650/jos.ess23188] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/02/2024] Open
Abstract
Phospholipids and surfactants form membranes and other self-assembled structures in water. However, it is not fully understood how the surrounding water (hydration water) is involved in their structure formation. In this paper, I summarize the results of our investigation of the long-range hydration state of phospholipids and surfactants at their surfaces by means of terahertz spectroscopy. By observing the collective rotational dynamics of water in the picosecond time scale, this technique allows us to observe not only the water directly bound to the solute, but also the weakly affected water outside of it. For example, PC phospholipids inhibit water dynamics over long distances, whereas PE phospholipids make water more mobile than bulk water. The causes of this difference in hydration and how it is involved in the structural formation of the membrane are reviewed.
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Affiliation(s)
- Mafumi Hishida
- Department of Chemistry, Faculty of Science, Tokyo University of Science
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8
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Hishida M, Kaneko A, Yamamura Y, Saito K. Contrasting Changes in Strongly and Weakly Bound Hydration Water of a Protein upon Denaturation. J Phys Chem B 2023; 127:6296-6305. [PMID: 37417885 PMCID: PMC10364084 DOI: 10.1021/acs.jpcb.3c02970] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2023] [Revised: 06/21/2023] [Indexed: 07/08/2023]
Abstract
Water is considered integral for the stabilization and function of proteins, which has recently attracted significant attention. However, the microscopic aspects of water ranging up to the second hydration shell, including strongly and weakly bound water at the sub-nanometer scale, are not yet well understood. Here, we combined terahertz spectroscopy, thermal measurements, and infrared spectroscopy to clarify how the strongly and weakly bound hydration water changes upon protein denaturation. With denaturation, that is, the exposure of hydrophobic groups in water and entanglement of hydrophilic groups, the number of strongly bound hydration water decreased, while the number of weakly bound hydration water increased. Even though the constraint of water due to hydrophobic hydration is weak, it extends to the second hydration shell as it is caused by the strengthening of hydrogen bonds between water molecules, which is likely the key microscopic mechanism for the destabilization of the native state due to hydration.
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Affiliation(s)
- Mafumi Hishida
- Department
of Chemistry, Faculty of Science, Tokyo
University of Science, 1-3 Kagurazaka, Shinjuku, Tokyo 162-8601, Japan
| | - Ayumi Kaneko
- Department
of Chemistry, Faculty of Pure and Applied Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8571, Japan
| | - Yasuhisa Yamamura
- Department
of Chemistry, Faculty of Pure and Applied Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8571, Japan
| | - Kazuya Saito
- Department
of Chemistry, Faculty of Pure and Applied Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8571, Japan
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Nakagawa H, Yamamoto N. Incoherent Neutron Scattering and Terahertz Time-Domain Spectroscopy on Protein and Hydration Water. Life (Basel) 2023; 13:life13020318. [PMID: 36836676 PMCID: PMC9961865 DOI: 10.3390/life13020318] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2022] [Accepted: 01/20/2023] [Indexed: 01/24/2023] Open
Abstract
Incoherent inelastic and quasi-elastic neutron scattering (INS) and terahertz time-domain spectroscopy (THz-TDS) are spectroscopy methods that directly detect molecular dynamics, with an overlap in the measured energy regions of each method. Due to the different characteristics of their probes (i.e., neutron and light), the information obtained and the sample conditions suitable for each method differ. In this review, we introduce the differences in the quantum beam properties of the two methods and their associated advantages and disadvantages in molecular spectroscopy. Neutrons are scattered via interaction with nuclei; one characteristic of neutron scattering is a large incoherent scattering cross-section of a hydrogen atom. INS records the auto-correlation functions of atomic positions. By using the difference in neutron scattering cross-sections of isotopes in multi-component systems, some molecules can be selectively observed. In contrast, THz-TDS observes the cross-correlation function of dipole moments. In water-containing biomolecular samples, the absorption of water molecules is particularly large. While INS requires large-scale experimental facilities, such as accelerators and nuclear reactors, THz-TDS can be performed at the laboratory level. In the analysis of water molecule dynamics, INS is primarily sensitive to translational diffusion motion, while THz-TDS observes rotational motion in the spectrum. The two techniques are complementary in many respects, and a combination of the two is very useful in analyzing the dynamics of biomolecules and hydration water.
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Affiliation(s)
- Hiroshi Nakagawa
- Materials Sciences Research Center, Japan Atomic Energy Agency, Tokai-mura 319-1195, Ibaraki, Japan
- J-PARC Center, Japan Atomic Energy Agency, Tokai-mura 319-1195, Ibaraki, Japan
- Correspondence: (H.N.); (N.Y.)
| | - Naoki Yamamoto
- Division of Biophysics, Department of Physiology, Jichi Medical University, Shimotsuke 329-0498, Tochigi, Japan
- Correspondence: (H.N.); (N.Y.)
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Shiomoto S, Inoue K, Higuchi H, Nishimura SN, Takaba H, Tanaka M, Kobayashi M. Characterization of Hydration Water Bound to Choline Phosphate-Containing Polymers. Biomacromolecules 2022; 23:2999-3008. [PMID: 35736642 DOI: 10.1021/acs.biomac.2c00484] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Zwitterionic methacrylate polymers with either choline phosphate (CP) (poly(MCP)) or phosphorylcholine (PC) (poly(MPC)) side groups were analyzed to characterize the bound hydration water molecules as nonfreezing water (NFW), intermediate water (IW), or free water (FW). This characterization was carried out by differential scanning calorimetry (DSC) of polymer/water systems, and the enthalpy changes of cold crystallization and melting were determined. The electron pair orientation of CP is opposite to that of PC, and the former binds the alkyl terminal groups at the phosphate esters. The numbers of NFW and IW molecules per monomer unit of poly(MCP) with an isopropyl terminal group were estimated to be 10.7 and 11.3 mol/mol, respectively, which were slightly greater than those of the poly(MCP) bearing an ethyl terminal group. More NFW and IW molecules hydrated the phosphobetaine polyzwitterions, poly(MCP) and poly(MPC), compared with carboxybetaine and sulfobetaine polymers. Moreover, the hydration states of polyelectrolytes were compared with the zwitterionic polymers. Finally, we discuss the relationship between the amount of hydration water and bio-inert properties.
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Affiliation(s)
- Shohei Shiomoto
- Graduate School of Engineering, Kogakuin University, Tokyo 192-0015, Japan
| | - Kaito Inoue
- Graduate School of Engineering, Kogakuin University, Tokyo 192-0015, Japan
| | - Hayato Higuchi
- Graduate School of Engineering, Kogakuin University, Tokyo 192-0015, Japan
| | - Shin-Nosuke Nishimura
- Institute for Materials Chemistry and Engineering, Kyushu University, Fukuoka 819-0395, Japan
| | - Hiromitsu Takaba
- School of Advanced Engineering, Kogakuin University, Tokyo 192-0015, Japan
| | - Masaru Tanaka
- Institute for Materials Chemistry and Engineering, Kyushu University, Fukuoka 819-0395, Japan
| | - Motoyasu Kobayashi
- School of Advanced Engineering, Kogakuin University, Tokyo 192-0015, Japan
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