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Touqeer M, Esmaeilzadeh B, Meng W, Wang J, Maqbool SA, Zheng S, Junwei L, Hou Y, Lu Q. A novel STM for quality atomic resolution with piezoelectric motor of high compactness and simplicity. Ultramicroscopy 2024; 263:113983. [PMID: 38749338 DOI: 10.1016/j.ultramic.2024.113983] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Revised: 03/14/2024] [Accepted: 04/25/2024] [Indexed: 06/16/2024]
Abstract
Scanning tunneling microscope (STM) is a renowned scientific tool for obtaining high-resolution atomic images of materials. Herein, we present an innovative design of the scanning unit with a compact yet powerful inertial piezoelectric motor inspired by the Spider Drive motor principle. The scanning unit mainly consists of a small 9 mm long piezoelectric tube scanner (PTS), one end of which is coaxially connected to the main sapphire body of the STM. Of particular emphasis in this design is the piezoelectric shaft (PS), constructed from piezoelectric material instead of conventional metallic or zirconium materials. The PS is a rectangular piezoelectric stack composed of two piezoelectric plates, which are elastically clamped on the inner wall of the PTS via a spring strip. The PTS and PS expand and contract independently with each other to improve the inertial force and reduce the threshold voltage. To ensure the stability of the PS and balance the stepping performance of the inertial motor, a counterweight, and a matching conical spring are fixed at the tail of the PS. This innovative design allows for the assessment of scanning unit performance by applying a driving signal, threshold voltage is 50 V at room temperature. Step sizes vary from 0.1 to 1 µm by changing the driving signal at room temperature. Furthermore, we successfully obtained atomic-resolution images of a highly oriented pyrolytic graphite (HOPG) sample and low drift rates of 23.4 pm/min and 34.6 pm/min in X-Y plane and Z direction, respectively, under ambient conditions. This small, compact STM unit has the potential for the development of a rotatable STM for use in cryogen-free magnets, and superconducting magnets.
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Affiliation(s)
- Muhammad Touqeer
- High Magnetic Field Laboratory, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui 230031, People's Republic of China; University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
| | - Behnam Esmaeilzadeh
- High Magnetic Field Laboratory, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui 230031, People's Republic of China; University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
| | - Wenjie Meng
- High Magnetic Field Laboratory, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui 230031, People's Republic of China; Anhui Key Laboratory of Low-Energy Quantum Materials and Devices, High Magnetic Field Laboratory, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui 230031, China
| | - Jihao Wang
- High Magnetic Field Laboratory, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui 230031, People's Republic of China; Anhui Key Laboratory of Low-Energy Quantum Materials and Devices, High Magnetic Field Laboratory, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui 230031, China
| | - Syed Asad Maqbool
- High Magnetic Field Laboratory, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui 230031, People's Republic of China; University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
| | - Shaofeng Zheng
- High Magnetic Field Laboratory, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui 230031, People's Republic of China; University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
| | - Liu Junwei
- High Magnetic Field Laboratory, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui 230031, People's Republic of China; University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
| | - Yubin Hou
- High Magnetic Field Laboratory, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui 230031, People's Republic of China; Anhui Key Laboratory of Low-Energy Quantum Materials and Devices, High Magnetic Field Laboratory, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui 230031, China
| | - Qingyou Lu
- High Magnetic Field Laboratory, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui 230031, People's Republic of China; University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China; Anhui Key Laboratory of Low-Energy Quantum Materials and Devices, High Magnetic Field Laboratory, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui 230031, China; Anhui Laboratory of Advanced Photon Science and Technology, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China.
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Geng T, Wang J, Meng W, Zhang J, Feng Q, Hou Y, Lu Q. A Novel Atomically Resolved Scanning Tunneling Microscope Capable of Working in Cryogen-Free Superconducting Magnet. MICROMACHINES 2023; 14:637. [PMID: 36985044 PMCID: PMC10059664 DOI: 10.3390/mi14030637] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Revised: 03/04/2023] [Accepted: 03/09/2023] [Indexed: 06/18/2023]
Abstract
We present a novel homebuilt scanning tunneling microscope (STM) with atomic resolution integrated into a cryogen-free superconducting magnet system with a variable temperature insert. The STM head is designed as a nested structure of double piezoelectric tubes (PTs), which are connected coaxially through a sapphire frame whose top has a sample stage. A single shaft made of tantalum, with the STM tip on top, is held firmly by a spring strip inside the internal PT. The external PT drives the shaft to the tip-sample junction based on the SpiderDrive principle, and the internal PT completes the subsequent scanning and imaging work. The STM head is simple, compact, and easy to assemble. The excellent performance of the device was demonstrated by obtaining atomic-resolution images of graphite and low drift rates of 30.2 pm/min and 41.4 pm/min in the X-Y plane and Z direction, respectively, at 300K. In addition, we cooled the sample to 1.6 K and took atomic-resolution images of graphite and NbSe2. Finally, we performed a magnetic field sweep test from 0 T to 9 T at 70 K, obtaining distinct graphite images with atomic resolution under varying magnetic fields. These experiments show our newly developed STM's high stability, vibration resistance, and immunity to high magnetic fields.
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Affiliation(s)
- Tao Geng
- High Magnetic Field Laboratory, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China
- University of Science and Technology of China, Hefei 230026, China
| | - Jihao Wang
- High Magnetic Field Laboratory, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei 230031, China
- High Magnetic Field Laboratory of Anhui Province, Hefei 230031, China
| | - Wenjie Meng
- High Magnetic Field Laboratory, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei 230031, China
- High Magnetic Field Laboratory of Anhui Province, Hefei 230031, China
| | - Jing Zhang
- High Magnetic Field Laboratory, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei 230031, China
- High Magnetic Field Laboratory of Anhui Province, Hefei 230031, China
| | - Qiyuan Feng
- High Magnetic Field Laboratory, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei 230031, China
- High Magnetic Field Laboratory of Anhui Province, Hefei 230031, China
| | - Yubin Hou
- High Magnetic Field Laboratory, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei 230031, China
- High Magnetic Field Laboratory of Anhui Province, Hefei 230031, China
| | - Qingyou Lu
- High Magnetic Field Laboratory, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China
- University of Science and Technology of China, Hefei 230026, China
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei 230031, China
- High Magnetic Field Laboratory of Anhui Province, Hefei 230031, China
- Anhui Laboratory of Advanced Photon Science and Technology, University of Science and Technology of China, Hefei 230026, China
- Hefei National Research Center for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei 230026, China
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Geng T, Wang J, Meng W, Zhang J, Feng Q, Lu Y, Hou Y, Lu Q. A cryogen-free superconducting magnet based scanning tunneling microscope for liquid phase measurement. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2023; 94:033705. [PMID: 37012773 DOI: 10.1063/5.0121761] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Accepted: 02/25/2023] [Indexed: 06/19/2023]
Abstract
Scanning tunneling microscopes (STMs) that work in ultra-high vacuum and low temperatures are commonly used in condensed matter physics, but an STM that works in a high magnetic field to image chemical molecules and active biomolecules in solution has never been reported. Here, we present a liquid-phase STM for use in a 10 T cryogen-free superconducting magnet. The STM head is mainly constructed with two piezoelectric tubes. A large piezoelectric tube is fixed at the bottom of a tantalum frame to perform large-area imaging. A small piezoelectric tube mounted at the free end of the large one performs high-precision imaging. The imaging area of the large piezoelectric tube is four times that of the small one. The high compactness and rigidity of the STM head make it functional in a cryogen-free superconducting magnet with huge vibrations. The performance of our homebuilt STM was demonstrated by the high-quality, atomic-resolution images of a graphite surface, as well as the low drift rates in the X-Y plane and Z direction. Furthermore, we successfully obtained atomic-resolution images of graphite in solution conditions while sweeping the field from 0 to 10 T, illustrating the new STM's immunity to magnetic fields. The sub-molecular images of active antibodies and plasmid DNA in solution conditions show the device's capability of imaging biomolecules. Our STM is suitable for studying chemical molecules and active biomolecules in high magnetic fields.
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Affiliation(s)
- Tao Geng
- High Magnetic Field Laboratory, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui 230031, China
| | - Jihao Wang
- High Magnetic Field Laboratory, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui 230031, China
| | - Wengjie Meng
- High Magnetic Field Laboratory, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui 230031, China
| | - Jing Zhang
- High Magnetic Field Laboratory, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui 230031, China
| | - Qiyuan Feng
- High Magnetic Field Laboratory, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui 230031, China
| | - Yalin Lu
- University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Yubin Hou
- High Magnetic Field Laboratory, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui 230031, China
| | - Qingyou Lu
- High Magnetic Field Laboratory, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui 230031, China
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Abstract
Enzymatic reactions and noncovalent (i.e., supramolecular) interactions are two fundamental nongenetic attributes of life. Enzymatic noncovalent synthesis (ENS) refers to a process where enzymatic reactions control intermolecular noncovalent interactions for spatial organization of higher-order molecular assemblies that exhibit emergent properties and functions. Like enzymatic covalent synthesis (ECS), in which an enzyme catalyzes the formation of covalent bonds to generate individual molecules, ENS is a unifying theme for understanding the functions, morphologies, and locations of molecular ensembles in cellular environments. This review intends to provide a summary of the works of ENS within the past decade and emphasize ENS for functions. After comparing ECS and ENS, we describe a few representative examples where nature uses ENS, as a rule of life, to create the ensembles of biomacromolecules for emergent properties/functions in a myriad of cellular processes. Then, we focus on ENS of man-made (synthetic) molecules in cell-free conditions, classified by the types of enzymes. After that, we introduce the exploration of ENS of man-made molecules in the context of cells by discussing intercellular, peri/intracellular, and subcellular ENS for cell morphogenesis, molecular imaging, cancer therapy, and other applications. Finally, we provide a perspective on the promises of ENS for developing molecular assemblies/processes for functions. This review aims to be an updated introduction for researchers who are interested in exploring noncovalent synthesis for developing molecular science and technologies to address societal needs.
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Affiliation(s)
- Hongjian He
- Department of Chemistry, Brandeis University, 415 South Street, Waltham, Massachusetts 02454, United States
| | - Weiyi Tan
- Department of Chemistry, Brandeis University, 415 South Street, Waltham, Massachusetts 02454, United States
| | - Jiaqi Guo
- Department of Chemistry, Brandeis University, 415 South Street, Waltham, Massachusetts 02454, United States
| | - Meihui Yi
- Department of Chemistry, Brandeis University, 415 South Street, Waltham, Massachusetts 02454, United States
| | - Adrianna N Shy
- Department of Chemistry, Brandeis University, 415 South Street, Waltham, Massachusetts 02454, United States
| | - Bing Xu
- Department of Chemistry, Brandeis University, 415 South Street, Waltham, Massachusetts 02454, United States
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Martínez-Pedrero F, Ortega F, Codina J, Calero C, Rubio RG. Controlled disassembly of colloidal aggregates confined at fluid interfaces using magnetic dipolar interactions. J Colloid Interface Sci 2020; 560:388-397. [DOI: 10.1016/j.jcis.2019.10.008] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Revised: 09/03/2019] [Accepted: 10/03/2019] [Indexed: 10/25/2022]
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Wu J, Zheng Z, Chong Y, Li X, Pu L, Tang Q, Yang L, Wang X, Wang F, Liang G. Immune Responsive Release of Tacrolimus to Overcome Organ Transplant Rejection. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2018; 30:e1805018. [PMID: 30255648 DOI: 10.1002/adma.201805018] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Revised: 09/01/2018] [Indexed: 06/08/2023]
Abstract
Transplant rejection is the key problem in organ transplantation and, in clinic, immunosuppressive agents such as tacrolimus are directly administered to the recipients after surgery for T-cell inhibition. However, direct administration of tacrolimus may bring severe side effects to the recipients. Herein, by rational design of two hydrogelators NapPhePheGluTyrOH (1) and Nap d-Phe dPheGluTyrOH (2), a facile method of immune responsive release of tacrolimus is developed from their hydrogels to overcome organ transplantation rejection. Upon incubation with protein tyrosine kinase, which is activated in T cells after organ transplantation, the tacrolimus-encapsulating Gel 1 or Gel 2 is disassembled to release tacrolimus. Cell experiments show that both Gel 1 and Gel 2 have better inhibition effect on the activated T cells than free drug tacrolimus. Liver transplantation experiments indicate that, after 7 days of treatment of same dose tacrolimus, the recipient rats in the Gel 2 group show significantly extended median survival time of 22 days while the recipients treated with conventional tacrolimus medication have a median survival time of 13 days. It is expected herein that this "smart" facile method of immune responsive release of tacrolimus can be applied to overcome organ transplantation rejection in clinic in the near future.
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Affiliation(s)
- Jindao Wu
- Key Laboratory of Living Donor Liver Transplantation of Ministry of Public Health, Department of Liver Transplantation Center of The First Affiliated Hospital of Nanjing Medical University, Analysis Center, Nanjing Medical University, 140 Hanzhong Road, Nanjing, Jiangsu, 210029, China
| | - Zhen Zheng
- CAS Key Laboratory of Soft Matter Chemistry, Department of Chemistry, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui, 230026, China
| | - Yuanyuan Chong
- Department of Chemical Physics, School of Chemistry and Materials Science, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui, 230026, China
| | - Xiangcheng Li
- Key Laboratory of Living Donor Liver Transplantation of Ministry of Public Health, Department of Liver Transplantation Center of The First Affiliated Hospital of Nanjing Medical University, Analysis Center, Nanjing Medical University, 140 Hanzhong Road, Nanjing, Jiangsu, 210029, China
| | - Liyong Pu
- Key Laboratory of Living Donor Liver Transplantation of Ministry of Public Health, Department of Liver Transplantation Center of The First Affiliated Hospital of Nanjing Medical University, Analysis Center, Nanjing Medical University, 140 Hanzhong Road, Nanjing, Jiangsu, 210029, China
| | - Qiyun Tang
- Key Laboratory of Living Donor Liver Transplantation of Ministry of Public Health, Department of Liver Transplantation Center of The First Affiliated Hospital of Nanjing Medical University, Analysis Center, Nanjing Medical University, 140 Hanzhong Road, Nanjing, Jiangsu, 210029, China
| | - Liu Yang
- Key Laboratory of Living Donor Liver Transplantation of Ministry of Public Health, Department of Liver Transplantation Center of The First Affiliated Hospital of Nanjing Medical University, Analysis Center, Nanjing Medical University, 140 Hanzhong Road, Nanjing, Jiangsu, 210029, China
| | - Xuehao Wang
- Key Laboratory of Living Donor Liver Transplantation of Ministry of Public Health, Department of Liver Transplantation Center of The First Affiliated Hospital of Nanjing Medical University, Analysis Center, Nanjing Medical University, 140 Hanzhong Road, Nanjing, Jiangsu, 210029, China
| | - Fuqiang Wang
- Key Laboratory of Living Donor Liver Transplantation of Ministry of Public Health, Department of Liver Transplantation Center of The First Affiliated Hospital of Nanjing Medical University, Analysis Center, Nanjing Medical University, 140 Hanzhong Road, Nanjing, Jiangsu, 210029, China
| | - Gaolin Liang
- CAS Key Laboratory of Soft Matter Chemistry, Department of Chemistry, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui, 230026, China
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Chen X, Guo T, Hou Y, Zhang J, Meng W, Lu Q. A High Rigidity and Precision Scanning Tunneling Microscope with Decoupled XY and Z Scans. SCANNING 2017; 2017:1020476. [PMID: 29270242 PMCID: PMC5706072 DOI: 10.1155/2017/1020476] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Accepted: 10/15/2017] [Indexed: 06/07/2023]
Abstract
A new scan-head structure for the scanning tunneling microscope (STM) is proposed, featuring high scan precision and rigidity. The core structure consists of a piezoelectric tube scanner of quadrant type (for XY scans) coaxially housed in a piezoelectric tube with single inner and outer electrodes (for Z scan). They are fixed at one end (called common end). A hollow tantalum shaft is coaxially housed in the XY-scan tube and they are mutually fixed at both ends. When the XY scanner scans, its free end will bring the shaft to scan and the tip which is coaxially inserted in the shaft at the common end will scan a smaller area if the tip protrudes short enough from the common end. The decoupled XY and Z scans are desired for less image distortion and the mechanically reduced scan range has the superiority of reducing the impact of the background electronic noise on the scanner and enhancing the tip positioning precision. High quality atomic resolution images are also shown.
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Affiliation(s)
- Xu Chen
- Sino-German Engineering College, TongJi University, Shanghai 201804, China
| | - Tengfei Guo
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory of the Chinese Academy of Sciences, Hefei, Anhui 230031, China
| | - Yubin Hou
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory of the Chinese Academy of Sciences, Hefei, Anhui 230031, China
| | - Jing Zhang
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory of the Chinese Academy of Sciences, Hefei, Anhui 230031, China
| | - Wenjie Meng
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory of the Chinese Academy of Sciences, Hefei, Anhui 230031, China
| | - Qingyou Lu
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory of the Chinese Academy of Sciences, Hefei, Anhui 230031, China
- Hefei National Laboratory for Physical Sciences at Microscale, University of Science and Technology of China, Hefei, Anhui 230026, China
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Wu C, Zheng Z, Guo Y, Tian C, Xue Q, Liang G. Fluorine substitution enhances the self-assembling ability of hydrogelators. NANOSCALE 2017; 9:11429-11433. [PMID: 28770916 DOI: 10.1039/c7nr02499a] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
When supramolecular hydrogels are applied as tissue culture scaffolds, their mechanical strength and biocompatibility are the two most important factors that must be considered. However, systematic studies on the structure-mechanical property (or structure-cytotoxicity) relationship of hydrogels are rare. Herein, we rationally designed three hydrogelators and their corresponding phosphate precursors, and systematically studied their self-assembling ability and cytotoxicity. The results indicated that fluorine substitution, but not trifluoromethyl substitution with more fluorine atoms, to the phenylalanine motif enhanced the self-assembling ability and cytotoxicity of the hydrogelators (or precursors). We envision that our preliminary study of hydrogelator fluorination would provide a strategy for the development of supramolecular hydrogels for wider biomedical applications.
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Affiliation(s)
- Chengfan Wu
- CAS Key Laboratory of Soft Matter Chemistry, Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, China.
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