Ihor M. Tkachenko, Yuriy I. Kurioz, Ruslan M. Kravchuk, Alexander L. Tolstov, Anatoliy V. Glushchenko, Vassili G. Nazarenko and Valery V. Shevchenko
A novel light-responsive poly(arylene ether) copolymer with both azobenzene and perfluorinated biphenylene units as well as meta-linked fragments in the main polymer chain is synthesized. The copolymer is synthesized using aromatic nucleophilic substitution reaction from decafluorobiphenyl and two dihydroxyl-substituted monomers, fluorinated bis-azobenzene-based phenol derivative, and resorcinol. The chemical structure of the copolymer is characterized using 1H, 19F NMR, FTIR, Raman and UV/vis spectroscopy techniques. The polymer shows remarkable solubility in organic solvents resulting in the formation of robust, self-supporting films. It displays impressive mechanical characteristics as well as remarkable resistance to thermo-oxidative degradation. Under UV light irradiation, photoisomerization occurs both in solution and in the solid copolymer film. The solid polymer films exhibit intense and stable birefringence changes upon the irradiation, enabling the fabrication of diffraction gratings. The study indicates that this synthetic approach is a simple and effective method for designing light-responsive materials.
{"title":"Development of a light-responsive fluorinated poly(arylene ether) copolymer containing azobenzene groups in the main polymer chain†","authors":"Ihor M. Tkachenko, Yuriy I. Kurioz, Ruslan M. Kravchuk, Alexander L. Tolstov, Anatoliy V. Glushchenko, Vassili G. Nazarenko and Valery V. Shevchenko","doi":"10.1039/D3ME00150D","DOIUrl":"10.1039/D3ME00150D","url":null,"abstract":"<p >A novel light-responsive poly(arylene ether) copolymer with both azobenzene and perfluorinated biphenylene units as well as <em>meta</em>-linked fragments in the main polymer chain is synthesized. The copolymer is synthesized using aromatic nucleophilic substitution reaction from decafluorobiphenyl and two dihydroxyl-substituted monomers, fluorinated bis-azobenzene-based phenol derivative, and resorcinol. The chemical structure of the copolymer is characterized using <small><sup>1</sup></small>H, <small><sup>19</sup></small>F NMR, FTIR, Raman and UV/vis spectroscopy techniques. The polymer shows remarkable solubility in organic solvents resulting in the formation of robust, self-supporting films. It displays impressive mechanical characteristics as well as remarkable resistance to thermo-oxidative degradation. Under UV light irradiation, photoisomerization occurs both in solution and in the solid copolymer film. The solid polymer films exhibit intense and stable birefringence changes upon the irradiation, enabling the fabrication of diffraction gratings. The study indicates that this synthetic approach is a simple and effective method for designing light-responsive materials.</p>","PeriodicalId":91,"journal":{"name":"Molecular Systems Design & Engineering","volume":" 2","pages":" 149-157"},"PeriodicalIF":3.6,"publicationDate":"2023-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135504576","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Taisei Kaku, Koichi Deura, Tomoka Yoshii, Daniel Citterio and Yuki Hiruta
The separation capacity of a column typically remains constant. By applying stimuli-responsive materials to the stationary phase, the separation capacity in a single column can be tuned; however, the separation mode is not completely switched. In this study, we aimed to develop a cation/anion-exchange mode switching chromatography approach, in which the monomer ratio is adjusted, enabling the surface charge to become either negative or positive in response to mobile phase pH. Three types of beads were prepared, each modified with a pH-responsive mixed-charge polymer combining a cationic monomer, a pH-responsive carboxylic acid monomer, a neutral monomer, and a cross-linking monomer. The composition ratio of the cationic monomer to the pH-responsive carboxylic acid monomer was set at 1 : 2 so that the cation-exchange mode occurs at a pH above the pKa and the anion-exchange mode occurs below the pKa. At a pH below the pKa, the retention factor of the negatively charged compound increased. In contrast, at a pH above the pKa, the retention factor of the positively charged compound increased, confirming the charge switching on the bead surface. Switching to the cation- and anion-exchange mode enabled the separation of five basic antidepressants and acidic non-steroidal anti-inflammatory drugs, respectively. Utilizing a pH-responsive mixed-charge polymer, we attributed a cation/anion-exchange mode to a single column.
{"title":"Cation/anion-exchange mode switching chromatography utilizing pH-responsive mixed charge polymer-modified silica beads†","authors":"Taisei Kaku, Koichi Deura, Tomoka Yoshii, Daniel Citterio and Yuki Hiruta","doi":"10.1039/D3ME00100H","DOIUrl":"10.1039/D3ME00100H","url":null,"abstract":"<p >The separation capacity of a column typically remains constant. By applying stimuli-responsive materials to the stationary phase, the separation capacity in a single column can be tuned; however, the separation mode is not completely switched. In this study, we aimed to develop a cation/anion-exchange mode switching chromatography approach, in which the monomer ratio is adjusted, enabling the surface charge to become either negative or positive in response to mobile phase pH. Three types of beads were prepared, each modified with a pH-responsive mixed-charge polymer combining a cationic monomer, a pH-responsive carboxylic acid monomer, a neutral monomer, and a cross-linking monomer. The composition ratio of the cationic monomer to the pH-responsive carboxylic acid monomer was set at 1 : 2 so that the cation-exchange mode occurs at a pH above the p<em>K</em><small><sub>a</sub></small> and the anion-exchange mode occurs below the p<em>K</em><small><sub>a</sub></small>. At a pH below the p<em>K</em><small><sub>a</sub></small>, the retention factor of the negatively charged compound increased. In contrast, at a pH above the p<em>K</em><small><sub>a</sub></small>, the retention factor of the positively charged compound increased, confirming the charge switching on the bead surface. Switching to the cation- and anion-exchange mode enabled the separation of five basic antidepressants and acidic non-steroidal anti-inflammatory drugs, respectively. Utilizing a pH-responsive mixed-charge polymer, we attributed a cation/anion-exchange mode to a single column.</p>","PeriodicalId":91,"journal":{"name":"Molecular Systems Design & Engineering","volume":" 1","pages":" 56-62"},"PeriodicalIF":3.6,"publicationDate":"2023-11-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2024/me/d3me00100h?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135446903","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Tongyi Wang, Yongsheng Liu, Jiawei Li, Jun Zhang, Jian Hou, Youguo Yan and Xiao Wang
Polyurethane (PU) materials have been widely used for developing microcapsules due to their excellent polymerization, encapsulation, and controlled release properties. These unique properties endow PU-based microcapsules with desired functions for enhanced oil recovery (EOR). However, there are some special requirements for PU-based microcapsules in their application of the EOR process, such as they are expected to exhibit good stability at room temperature but thermo-responsive swelling-release properties in the oil reservoir. To enhance the functionality of PU-based microcapsules for EOR, after validating the swelling-release behaviors of PU-based microcapsules, we employed all-atom molecular dynamics (MD) simulations to study the effects of molecular structure of PU-based polymers on thermo-responsivity of microcapsules. The simulation results demonstrate that the diisocyanate segments have significant influence on swelling behaviors of PUs. The different diisocyanate segments, including isophorone diisocyanate (IPDI), toluene diisocyanate (TDI), 4,4′-diphenylmethane diisocyanate (MDI), and hexamethylene diisocyanate (HDI), have different impacts on the flexibility of the polymer, which further influence the network structure of the polymer matrix. The different swelling behaviors of PU-based polymers were further analyzed from energetic and kinetic perspectives, and it is demonstrated that TDI–PU can combine stability and thermo-responsivity together. In addition, the introduction of anionic functional groups can further facilitate the swelling process. The findings in this study serve as a foundation for future studies toward the development of polymer flooding technology and provide valuable molecular insights into the swelling mechanism of PU-based polymers.
{"title":"Designing polyurethane-based microcapsules with tailored swelling behaviours for enhanced oil recovery†","authors":"Tongyi Wang, Yongsheng Liu, Jiawei Li, Jun Zhang, Jian Hou, Youguo Yan and Xiao Wang","doi":"10.1039/D3ME00137G","DOIUrl":"10.1039/D3ME00137G","url":null,"abstract":"<p >Polyurethane (PU) materials have been widely used for developing microcapsules due to their excellent polymerization, encapsulation, and controlled release properties. These unique properties endow PU-based microcapsules with desired functions for enhanced oil recovery (EOR). However, there are some special requirements for PU-based microcapsules in their application of the EOR process, such as they are expected to exhibit good stability at room temperature but thermo-responsive swelling-release properties in the oil reservoir. To enhance the functionality of PU-based microcapsules for EOR, after validating the swelling-release behaviors of PU-based microcapsules, we employed all-atom molecular dynamics (MD) simulations to study the effects of molecular structure of PU-based polymers on thermo-responsivity of microcapsules. The simulation results demonstrate that the diisocyanate segments have significant influence on swelling behaviors of PUs. The different diisocyanate segments, including isophorone diisocyanate (IPDI), toluene diisocyanate (TDI), 4,4′-diphenylmethane diisocyanate (MDI), and hexamethylene diisocyanate (HDI), have different impacts on the flexibility of the polymer, which further influence the network structure of the polymer matrix. The different swelling behaviors of PU-based polymers were further analyzed from energetic and kinetic perspectives, and it is demonstrated that TDI–PU can combine stability and thermo-responsivity together. In addition, the introduction of anionic functional groups can further facilitate the swelling process. The findings in this study serve as a foundation for future studies toward the development of polymer flooding technology and provide valuable molecular insights into the swelling mechanism of PU-based polymers.</p>","PeriodicalId":91,"journal":{"name":"Molecular Systems Design & Engineering","volume":" 1","pages":" 46-55"},"PeriodicalIF":3.6,"publicationDate":"2023-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134888591","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The emerging perovskite solar cells (PSCs) have been explored as the most promising photovoltaic technology in the past decade, with the sharp increase of the power conversion efficiency (PCE) from 3.8% to certified 26.1%, comparable to that of crystalline silicon solar cells. Compared to conventional PSCs, inverted PSCs show attractive advantages, such as high device stability, negligible hysteresis and excellent compatibility with flexible and tandem devices. Self-assembled monolayers (SAMs) have been considered as one of the most promising hole-transporting materials (HTMs) for inverted PSCs owing to their low costs and material consumption and simple device fabrication with high PCEs. This review summarizes the recent developments in highly efficient SAMs as HTMs for inverted PSCs. On the basis of the anchoring group, three categories of SAMs are identified and discussed: SAMs with phosphonic acid, SAMs with carboxylic acid, and SAMs based on other anchoring groups. Finally, a future outlook of SAMs for high-performance inverted PSCs is provided. We hope that this review will be useful for the further design of SAMs toward the eventual commercialization of PSCs.
在锚定基团的基础上,讨论了高性能倒钙钛矿太阳能电池中三种自组装单层空穴传输材料。
{"title":"Self-assembled monolayers as hole-transporting materials for inverted perovskite solar cells","authors":"Zhong-Rui Lan, Jiang-Yang Shao and Yu-Wu Zhong","doi":"10.1039/D3ME00144J","DOIUrl":"10.1039/D3ME00144J","url":null,"abstract":"<p >The emerging perovskite solar cells (PSCs) have been explored as the most promising photovoltaic technology in the past decade, with the sharp increase of the power conversion efficiency (PCE) from 3.8% to certified 26.1%, comparable to that of crystalline silicon solar cells. Compared to conventional PSCs, inverted PSCs show attractive advantages, such as high device stability, negligible hysteresis and excellent compatibility with flexible and tandem devices. Self-assembled monolayers (SAMs) have been considered as one of the most promising hole-transporting materials (HTMs) for inverted PSCs owing to their low costs and material consumption and simple device fabrication with high PCEs. This review summarizes the recent developments in highly efficient SAMs as HTMs for inverted PSCs. On the basis of the anchoring group, three categories of SAMs are identified and discussed: SAMs with phosphonic acid, SAMs with carboxylic acid, and SAMs based on other anchoring groups. Finally, a future outlook of SAMs for high-performance inverted PSCs is provided. We hope that this review will be useful for the further design of SAMs toward the eventual commercialization of PSCs.</p>","PeriodicalId":91,"journal":{"name":"Molecular Systems Design & Engineering","volume":" 12","pages":" 1440-1455"},"PeriodicalIF":3.6,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2023/me/d3me00144j?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135319612","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Qiushi Deng, José María Castillo-Robles, Ernane de Freitas Martins, Pablo Ordejón, Jan-Niclas Gorges, Philipp Eiden, Xiao-Bo Chen, Patrick Keil and Ivan Cole
An in-depth understanding of corrosion inhibitor behaviour(s) at the metal–solution interface governed by unique molecular features is the key premise to realising molecular tailoring for pronounced metal protection. This study investigated the distinct adsorption behaviours induced by merely replacing the chemical functionality upon benzothiazole, i.e., 2-mercaptobenzothiazole (2-MBT) and 2-aminobenzothiazole (2-ABT), towards electro-galvanised steel (ZE) corrosion using both experimental and theoretical approaches. Electrochemical results confirm that both inhibitor candidates act as corrosion inhibitors for ZE in NaCl solution. The underlying interactions of the inhibitor molecule with the targeting metal, dissolved metal ions and corrosion products were explored by means of X-ray photoelectron spectroscopy, focused ion beam scanning electron microscopy and Raman spectroscopy. It is suggested that 2-MBT facilitates the precipitation upon the ZE by complexing with the released Zn2+ in solution, while 2-ABT promotes preferentially thin inhibitor film formation initiated by chemisorption. Density functional theory (DFT) reveals that at high concentrations the molecules tend to adsorb vertically (slightly tilted) at the surface, where the presented heteroatoms enhance surface–molecule interaction. In addition, DFT suggests that the strong binding strength of 2-MBT could facilitate the formation of complexes with displaced Zn. Based on the proposed mechanisms, the adsorption stability upon polarised ZE surfaces was determined, which reveals that 2-MBT forms a thick inhibitor layer at a relatively high polarisation state, whereas 2-ABT dissociates from the surface with the increasing value of surface overpotential. The findings of this study provide structural understanding that underpins inhibitor tailoring and molecular design to achieve the desired inhibition properties.
深入了解腐蚀抑制剂在金属-溶液界面上受独特分子特征支配的行为,是实现分子定制以提供明显金属保护的关键前提。本研究采用实验和理论方法,研究了仅通过更换苯并噻唑(即 2-巯基苯并噻唑 (2-MBT) 和 2-氨基苯并噻唑 (2-ABT))的化学官能团而引起的电镀锌钢 (ZE) 腐蚀的不同吸附行为。电化学结果证实,这两种候选抑制剂都是 NaCl 溶液中 ZE 的腐蚀抑制剂。通过 X 射线光电子能谱、聚焦离子束扫描电子显微镜和拉曼光谱,研究了抑制剂分子与目标金属、溶解金属离子和腐蚀产物之间的潜在相互作用。结果表明,2-MBT 通过与溶液中释放的 Zn2+ 复配,促进了 ZE 上的沉淀,而 2-ABT 则通过化学吸附作用优先促进了抑制剂薄膜的形成。密度泛函理论(DFT)显示,在高浓度下,分子倾向于垂直(略微倾斜)吸附在表面上,在这种情况下,所呈现的杂原子会增强表面与分子之间的相互作用。此外,DFT 还表明,2-MBT 的强结合力可促进与移位的 Zn 形成复合物。根据所提出的机制,测定了极化 ZE 表面的吸附稳定性,结果表明 2-MBT 在相对较高的极化状态下会形成较厚的抑制剂层,而 2-ABT 则会随着表面过电势值的增加而从表面解离。本研究的发现为抑制剂的定制和分子设计提供了结构上的理解,从而实现理想的抑制特性。
{"title":"Inhibitory behaviour and adsorption stability of benzothiazole derivatives as corrosion inhibitors towards galvanised steel†","authors":"Qiushi Deng, José María Castillo-Robles, Ernane de Freitas Martins, Pablo Ordejón, Jan-Niclas Gorges, Philipp Eiden, Xiao-Bo Chen, Patrick Keil and Ivan Cole","doi":"10.1039/D3ME00153A","DOIUrl":"10.1039/D3ME00153A","url":null,"abstract":"<p >An in-depth understanding of corrosion inhibitor behaviour(s) at the metal–solution interface governed by unique molecular features is the key premise to realising molecular tailoring for pronounced metal protection. This study investigated the distinct adsorption behaviours induced by merely replacing the chemical functionality upon benzothiazole, <em>i.e.</em>, 2-mercaptobenzothiazole (2-MBT) and 2-aminobenzothiazole (2-ABT), towards electro-galvanised steel (ZE) corrosion using both experimental and theoretical approaches. Electrochemical results confirm that both inhibitor candidates act as corrosion inhibitors for ZE in NaCl solution. The underlying interactions of the inhibitor molecule with the targeting metal, dissolved metal ions and corrosion products were explored by means of X-ray photoelectron spectroscopy, focused ion beam scanning electron microscopy and Raman spectroscopy. It is suggested that 2-MBT facilitates the precipitation upon the ZE by complexing with the released Zn<small><sup>2+</sup></small> in solution, while 2-ABT promotes preferentially thin inhibitor film formation initiated by chemisorption. Density functional theory (DFT) reveals that at high concentrations the molecules tend to adsorb vertically (slightly tilted) at the surface, where the presented heteroatoms enhance surface–molecule interaction. In addition, DFT suggests that the strong binding strength of 2-MBT could facilitate the formation of complexes with displaced Zn. Based on the proposed mechanisms, the adsorption stability upon polarised ZE surfaces was determined, which reveals that 2-MBT forms a thick inhibitor layer at a relatively high polarisation state, whereas 2-ABT dissociates from the surface with the increasing value of surface overpotential. The findings of this study provide structural understanding that underpins inhibitor tailoring and molecular design to achieve the desired inhibition properties.</p>","PeriodicalId":91,"journal":{"name":"Molecular Systems Design & Engineering","volume":" 1","pages":" 29-45"},"PeriodicalIF":3.6,"publicationDate":"2023-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135261206","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Mohammad Bashiri, Mona Hosseini-Sarvari and Sara Fakhraee
A crucial challenge in using organo-metal complexes for photocatalytic organic reactions is the need to develop applications of homogeneous photocatalysts that can effectively function under visible light conditions. For the first time, the use of binuclear complexes containing ferrocenyl-hydrazides as a ligand and nickel or copper as central metals as homogeneous photocatalysts in the oxidation of organic compounds is presented. The new organometal photocatalysts were prepared and identified using techniques, such as FT-IR spectroscopy, NMR spectroscopy, XRD, XRF, XPS, SEM, TGA, EDX, UV-visible, and photocurrent measurements. The oxidation of benzylic C(sp3)–H bonds to produce oxygenated molecules and the selective conversion of C–C double bonds to benzaldehyde can be achieved using bis-ferrocenyl hydrazide complexes with electron-withdrawing or electron-donating groups on the hydrazide moiety under visible-light irradiation in an air atmosphere, at ambient temperature and without the need for external oxidants. The synthesized complexes also can be used to oxygenate 1H-indole to 1H-indole-2,3-dione. The investigation of the role of donating and withdrawing functional groups in the synthesized complexes for selected oxidation reactions is a significant benefit of this report. It was found that only the [(FcHz)2Ni] and [(FcHz)2Cu] complexes without functional groups were able to provide a suitable response in the oxidation of the compounds. Additionally, the theoretical DFT and TD-DFT methodologies enabled us to describe the photocatalytic oxidation behavior of these metal complexes. The calculations showed conformational changes in the structure of metal complexes after oxidation. The molecular orbital and natural transition orbital analyses revealed the nature of electronic transitions in the UV-visible absorption bands.
{"title":"Bis-ferrocenyl-hydrazide metal complexes: studying electronic functional groups as newly potent homogeneous photocatalysts for C(sp3)–H and C(sp2)–H bond oxidation utilizing visible light condition†","authors":"Mohammad Bashiri, Mona Hosseini-Sarvari and Sara Fakhraee","doi":"10.1039/D3ME00133D","DOIUrl":"10.1039/D3ME00133D","url":null,"abstract":"<p >A crucial challenge in using organo-metal complexes for photocatalytic organic reactions is the need to develop applications of homogeneous photocatalysts that can effectively function under visible light conditions. For the first time, the use of binuclear complexes containing ferrocenyl-hydrazides as a ligand and nickel or copper as central metals as homogeneous photocatalysts in the oxidation of organic compounds is presented. The new organometal photocatalysts were prepared and identified using techniques, such as FT-IR spectroscopy, NMR spectroscopy, XRD, XRF, XPS, SEM, TGA, EDX, UV-visible, and photocurrent measurements. The oxidation of benzylic C(sp<small><sup>3</sup></small>)–H bonds to produce oxygenated molecules and the selective conversion of C–C double bonds to benzaldehyde can be achieved using bis-ferrocenyl hydrazide complexes with electron-withdrawing or electron-donating groups on the hydrazide moiety under visible-light irradiation in an air atmosphere, at ambient temperature and without the need for external oxidants. The synthesized complexes also can be used to oxygenate 1<em>H</em>-indole to 1<em>H</em>-indole-2,3-dione. The investigation of the role of donating and withdrawing functional groups in the synthesized complexes for selected oxidation reactions is a significant benefit of this report. It was found that only the [(FcHz)<small><sub>2</sub></small>Ni] and [(FcHz)<small><sub>2</sub></small>Cu] complexes without functional groups were able to provide a suitable response in the oxidation of the compounds. Additionally, the theoretical DFT and TD-DFT methodologies enabled us to describe the photocatalytic oxidation behavior of these metal complexes. The calculations showed conformational changes in the structure of metal complexes after oxidation. The molecular orbital and natural transition orbital analyses revealed the nature of electronic transitions in the UV-visible absorption bands.</p>","PeriodicalId":91,"journal":{"name":"Molecular Systems Design & Engineering","volume":" 1","pages":" 112-139"},"PeriodicalIF":3.6,"publicationDate":"2023-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135261209","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Victoria T. Adeleke, Oluwakemi Ebenezer, Madison Lasich and Samuel M. Mugo
Detection of cortisol (Cort), a stress hormone, is essential in monitoring chronic and mental health stress. As such, there is growing interest in the development of cortisol molecularly imprinted polymers (MIPs) as molecular receptors for sensor development. Of the cortisol MIPs described in the literature, the optimization of the functional monomers has been through trial-and-error experimentation. Through a computational approach, the number of optimization experiments can be reduced, which is time efficient and cost effective, while reducing chemical wastage. In addition to density functional theory (DFT) calculations, this study used an atomistic molecular dynamics simulation approach that resembles that of the real-life experimental methods to elucidate the compatibility of template-monomer-crosslinkers-solvent for cortisol MIP receptors that can efficiently recognize and capture cortisol from biological fluids. The functional monomer investigated were 4-vinylpyridine (4VP), acrylic acid (AA), acrylamide (AM), glycidyl methacrylate (GMA), 2-hydroxyethyl methacrylate (HEMA) and methylacrylic acid (MAA) with ethylene glycol dimethacrylate (EGDMA) as the crosslinker. The intermolecular hydrogen bonds and the template-monomer binding energies obtained through DFT suggested Cort-MAA as the most stable complex both in the gas phase and solution. Considering the calculated solvent energies, acetonitrile was recommended as a porogenic solvent. Through molecular dynamics simulation, various parameters were analyzed to explain the compatibility of the functional monomer with the cortisol template in the MIP development. From blend analysis of template-monomer, Cort-4VP was found to be the most miscible complex. For template-monomer-crosslinker (EGDMA), the mean square displacement (MSD) and diffusion coefficient analyses indicated 1 : 2 (cortisol/monomer) as the ratio in which the complexes are most stable. The highest peaks observed from the Radial distribution function were for Cort-MAA and Cort-AA at 1 : 4 indicating better interactions of the functional monomers with the Cort. Investigating the effect of solvents for template-monomer-crosslinker-solvent, the lowest MSD was at 1 : 4 with three complexes having the lowest values for solubility parameters at 1 : 4 confirming this ratio to be generally suitable for the composition of cortisol MIPs pre-polymerization.
{"title":"Theoretical insights into the compatibility of template-monomer-crosslinker-solvent for cortisol molecularly imprinted polymer pre-polymerization†","authors":"Victoria T. Adeleke, Oluwakemi Ebenezer, Madison Lasich and Samuel M. Mugo","doi":"10.1039/D3ME00077J","DOIUrl":"10.1039/D3ME00077J","url":null,"abstract":"<p >Detection of cortisol (Cort), a stress hormone, is essential in monitoring chronic and mental health stress. As such, there is growing interest in the development of cortisol molecularly imprinted polymers (MIPs) as molecular receptors for sensor development. Of the cortisol MIPs described in the literature, the optimization of the functional monomers has been through trial-and-error experimentation. Through a computational approach, the number of optimization experiments can be reduced, which is time efficient and cost effective, while reducing chemical wastage. In addition to density functional theory (DFT) calculations, this study used an atomistic molecular dynamics simulation approach that resembles that of the real-life experimental methods to elucidate the compatibility of template-monomer-crosslinkers-solvent for cortisol MIP receptors that can efficiently recognize and capture cortisol from biological fluids. The functional monomer investigated were 4-vinylpyridine (4VP), acrylic acid (AA), acrylamide (AM), glycidyl methacrylate (GMA), 2-hydroxyethyl methacrylate (HEMA) and methylacrylic acid (MAA) with ethylene glycol dimethacrylate (EGDMA) as the crosslinker. The intermolecular hydrogen bonds and the template-monomer binding energies obtained through DFT suggested Cort-MAA as the most stable complex both in the gas phase and solution. Considering the calculated solvent energies, acetonitrile was recommended as a porogenic solvent. Through molecular dynamics simulation, various parameters were analyzed to explain the compatibility of the functional monomer with the cortisol template in the MIP development. From blend analysis of template-monomer, Cort-4VP was found to be the most miscible complex. For template-monomer-crosslinker (EGDMA), the mean square displacement (MSD) and diffusion coefficient analyses indicated 1 : 2 (cortisol/monomer) as the ratio in which the complexes are most stable. The highest peaks observed from the Radial distribution function were for Cort-MAA and Cort-AA at 1 : 4 indicating better interactions of the functional monomers with the Cort. Investigating the effect of solvents for template-monomer-crosslinker-solvent, the lowest MSD was at 1 : 4 with three complexes having the lowest values for solubility parameters at 1 : 4 confirming this ratio to be generally suitable for the composition of cortisol MIPs pre-polymerization.</p>","PeriodicalId":91,"journal":{"name":"Molecular Systems Design & Engineering","volume":" 1","pages":" 99-111"},"PeriodicalIF":3.6,"publicationDate":"2023-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134980425","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Amphiphilic molecules spontaneously form self-assembly structures depending on physical conditions such as the molecular structure, concentration, and temperature. These structures exhibit various functionalities according to their morphology. The critical packing parameter (CPP) is used to correlate self-organized structures with the chemical composition. However, accurately calculating it requires information about both the molecular shape and molecular aggregates, making it challenging to apply directly in molecular design. We aimed to predict the self-assembled structure of a molecule directly from its chemical structure and to analyze the factors influencing it using machine learning. Dissipative particle dynamics simulations were used to reproduce many self-assembly structures comprising various chemical structures, and their CPPs were calculated. Machine learning models were built using the chemical structures as input data and the CPPs as output data. As a result, both random forest and the gated recurrent unit showed high prediction accuracy. Feature importance analysis and sample size dependence revealed that the amphiphilic nature of molecules significantly influences the self-assembly structures. Additionally, selecting an appropriate molecular structure representation for each algorithm is crucial. The study results should contribute to product development in the fields of materials science, materials chemistry, and medical materials.
{"title":"Machine learning prediction of self-assembly and analysis of molecular structure dependence on the critical packing parameter","authors":"Yuuki Ishiwatari, Takahiro Yokoyama, Tomoya Kojima, Taisuke Banno and Noriyoshi Arai","doi":"10.1039/D3ME00151B","DOIUrl":"10.1039/D3ME00151B","url":null,"abstract":"<p >Amphiphilic molecules spontaneously form self-assembly structures depending on physical conditions such as the molecular structure, concentration, and temperature. These structures exhibit various functionalities according to their morphology. The critical packing parameter (CPP) is used to correlate self-organized structures with the chemical composition. However, accurately calculating it requires information about both the molecular shape and molecular aggregates, making it challenging to apply directly in molecular design. We aimed to predict the self-assembled structure of a molecule directly from its chemical structure and to analyze the factors influencing it using machine learning. Dissipative particle dynamics simulations were used to reproduce many self-assembly structures comprising various chemical structures, and their CPPs were calculated. Machine learning models were built using the chemical structures as input data and the CPPs as output data. As a result, both random forest and the gated recurrent unit showed high prediction accuracy. Feature importance analysis and sample size dependence revealed that the amphiphilic nature of molecules significantly influences the self-assembly structures. Additionally, selecting an appropriate molecular structure representation for each algorithm is crucial. The study results should contribute to product development in the fields of materials science, materials chemistry, and medical materials.</p>","PeriodicalId":91,"journal":{"name":"Molecular Systems Design & Engineering","volume":" 1","pages":" 20-28"},"PeriodicalIF":3.6,"publicationDate":"2023-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2024/me/d3me00151b?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135102806","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Moki K. Thanusing, Peidong Shen, Brett L. Pollard and Luke A. Connal
Water-harvesting polymer materials have the potential to create new sources of potable water. However, a holistic understanding of the relationship between polymer structure and water-harvesting properties is lacking compared to studies on specific materials. In this work, we synthesised a library of methacrylic acid-co-poly(ethylene glycol) methyl ether methacrylate)-based hydrogels (poly(MAA-co-PEGMA)) with directed modifications, including composition, crosslinker lengths, crosslinking density and preparation of the hydrogels. MAA serves as a hygroscopic monomer while PEGMA provides hydrophilicity and thermoresponsive properties. The water uptake and release capabilities of all materials was also assessed. The optimised composition of the copolymer (75 : 5 : 20 MAA : EGDMA : PEGMA, mole%) has a water uptake of 98 mg g−1 polymer at 60% RH after 24 hours. The poly(MAA-co-PEGMA) materials also show a capability for water release, showing no significant decrease in water uptake capacity after repeated uptake-release cycles. Minimum temperatures for water release could easily be adjusted with polymer composition, ranging from 50–70 °C. The data presented in this body of work serves as a foundation for future efforts in creating thermoresponsive, water-harvesting polymers with real-world applications.
{"title":"Rational design of water-harvesting hydrogels†","authors":"Moki K. Thanusing, Peidong Shen, Brett L. Pollard and Luke A. Connal","doi":"10.1039/D3ME00132F","DOIUrl":"10.1039/D3ME00132F","url":null,"abstract":"<p >Water-harvesting polymer materials have the potential to create new sources of potable water. However, a holistic understanding of the relationship between polymer structure and water-harvesting properties is lacking compared to studies on specific materials. In this work, we synthesised a library of methacrylic acid-<em>co</em>-poly(ethylene glycol) methyl ether methacrylate)-based hydrogels (poly(MAA-<em>co</em>-PEGMA)) with directed modifications, including composition, crosslinker lengths, crosslinking density and preparation of the hydrogels. MAA serves as a hygroscopic monomer while PEGMA provides hydrophilicity and thermoresponsive properties. The water uptake and release capabilities of all materials was also assessed. The optimised composition of the copolymer (75 : 5 : 20 MAA : EGDMA : PEGMA, mole%) has a water uptake of 98 mg g<small><sup>−1</sup></small> polymer at 60% RH after 24 hours. The poly(MAA-<em>co</em>-PEGMA) materials also show a capability for water release, showing no significant decrease in water uptake capacity after repeated uptake-release cycles. Minimum temperatures for water release could easily be adjusted with polymer composition, ranging from 50–70 °C. The data presented in this body of work serves as a foundation for future efforts in creating thermoresponsive, water-harvesting polymers with real-world applications.</p>","PeriodicalId":91,"journal":{"name":"Molecular Systems Design & Engineering","volume":" 1","pages":" 63-72"},"PeriodicalIF":3.6,"publicationDate":"2023-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135102818","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yin Lu, Nan Li, Yaliang Peng, Mohamed Gamal Mohamed, Shiao-Wei Kuo and Kan Zhang
A facile and eco-friendly synthetic strategy has been developed to achieve a series of hydrogen bonding-rich bio-based thermosetting resins in this study. Using both safe and green solvents, we successfully synthesized target bio-based bisbenzoxazines (DcTa-fa, DcTa-sa, and DcTa-da) with high purity from five different naturally resourced raw materials. The chemical structures of the obtained bisbenzoxazine monomers were verified by nuclear magnetic resonance technology (including 1H and 13C NMR, two-dimensional 1H–1H nuclear Overhauser effect spectroscopy (NOESY), and 1H–13C heteronuclear multiple quantum coherence (HMQC)) and Fourier transform infrared spectroscopy (FT-IR). The polymerization processes were systematically investigated by differential scanning calorimetry (DSC) and in situ FT-IR analysis. Contact angle measurements were conducted and the corresponding results revealed tunable surface properties during the polymerization process of each bio-based bisbenzoxazine resin. In order to understand the relationship between the chemical structure and surface properties, more detailed FT-IR analyses were carried out to investigate the hydrogen bonding networks in the resulting polybenzoxazines. Notably, poly(DcTa-fa) presented excellent thermal stability (Td10 of 377 °C, Yc of 53.7 wt%) and strong adhesion strength (5.232 ± 0.26 MPa), while poly(DcTa-sa) and poly(DcTa-da) showed outstanding surface properties with very low surface free energy values (22.91 and 22.84 mJ m−2). These results highlight the utility of smart and sustainable benzoxazine chemistry and offer a facile and green synthetic approach to access hydrogen bonding-rich bio-based benzoxazine resins with many attractive properties.
{"title":"Facile and eco-friendly synthesis of hydrogen bonding-rich bio-based bisbenzoxazine resins with low surface free energy, strong adhesion strength and high thermal stability†","authors":"Yin Lu, Nan Li, Yaliang Peng, Mohamed Gamal Mohamed, Shiao-Wei Kuo and Kan Zhang","doi":"10.1039/D3ME00066D","DOIUrl":"10.1039/D3ME00066D","url":null,"abstract":"<p >A facile and eco-friendly synthetic strategy has been developed to achieve a series of hydrogen bonding-rich bio-based thermosetting resins in this study. Using both safe and green solvents, we successfully synthesized target bio-based bisbenzoxazines (<strong>DcTa-fa</strong>, <strong>DcTa-sa</strong>, and <strong>DcTa-da</strong>) with high purity from five different naturally resourced raw materials. The chemical structures of the obtained bisbenzoxazine monomers were verified by nuclear magnetic resonance technology (including <small><sup>1</sup></small>H and <small><sup>13</sup></small>C NMR, two-dimensional <small><sup>1</sup></small>H–<small><sup>1</sup></small>H nuclear Overhauser effect spectroscopy (NOESY), and <small><sup>1</sup></small>H–<small><sup>13</sup></small>C heteronuclear multiple quantum coherence (HMQC)) and Fourier transform infrared spectroscopy (FT-IR). The polymerization processes were systematically investigated by differential scanning calorimetry (DSC) and <em>in situ</em> FT-IR analysis. Contact angle measurements were conducted and the corresponding results revealed tunable surface properties during the polymerization process of each bio-based bisbenzoxazine resin. In order to understand the relationship between the chemical structure and surface properties, more detailed FT-IR analyses were carried out to investigate the hydrogen bonding networks in the resulting polybenzoxazines. Notably, <strong>poly(DcTa-fa)</strong> presented excellent thermal stability (<em>T</em><small><sub>d10</sub></small> of 377 °C, <em>Y</em><small><sub>c</sub></small> of 53.7 wt%) and strong adhesion strength (5.232 ± 0.26 MPa), while <strong>poly(DcTa-sa)</strong> and <strong>poly(DcTa-da)</strong> showed outstanding surface properties with very low surface free energy values (22.91 and 22.84 mJ m<small><sup>−2</sup></small>). These results highlight the utility of smart and sustainable benzoxazine chemistry and offer a facile and green synthetic approach to access hydrogen bonding-rich bio-based benzoxazine resins with many attractive properties.</p>","PeriodicalId":91,"journal":{"name":"Molecular Systems Design & Engineering","volume":" 1","pages":" 86-98"},"PeriodicalIF":3.6,"publicationDate":"2023-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136373933","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}