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Comparative studies of the biological efficacies of Ag and Ag-MgO nanocomposite formed by the green synthesis route. INORG CHEM COMMUN 2022. [DOI: 10.1016/j.inoche.2021.109082] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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Zhou S, Wei Z, Sun Y, Zhu Z, Xie Z, Ma H, Yin J, Wang J, Yang J. Biocompatible linear diamides derivative-nucleated biodegradable poly(ethylene succinate): Tailored crystallization kinetics, aggregated structure and thermal degradation. Polym Degrad Stab 2021. [DOI: 10.1016/j.polymdegradstab.2020.109428] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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Ma H, Wei Z, Zhou S, Zhu H, Tang J, Yin J, Yue J, Yang J. Supernucleation, crystalline structure and thermal stability of bacterially synthesized poly(3-hydroxybutyrate) polyester tailored by thymine as a biocompatible nucleating agent. Int J Biol Macromol 2020; 165:1562-1573. [PMID: 33058980 DOI: 10.1016/j.ijbiomac.2020.10.044] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Revised: 09/28/2020] [Accepted: 10/06/2020] [Indexed: 11/18/2022]
Abstract
Naturally occurring thymine (TM) was incorporated into bacterial poly(3-hydroxybutyrate) (PHB) polyester to fabricate a novel and green biocomposite. Both 0.5% and 1% TM exhibit supernucleation effect on PHB, and crystallization kinetics suggests TM significantly increased Tc and Xc, and substantially shortened t1/2 of PHB. Epitaxial nucleation caused by a perfect crystal lattice matching between PHB and TM, was proposed to elucidate nucleation mechanism of PHB. Hydrogen bond interaction exists between CO, C-O-C groups of PHB and -CH3 (or -CH)/-NH- group of TM. TM interacted with CO group of PHB crystalline phase rather than that of amorphous one. In addition, two new IR crystalline bands assigned to C-O-C group of PHB appeared in the presence of TM, which arises from shift of two amorphous ones, respectively. TM enhanced onset thermal degradation temperature of PHB, mainly attributed to increased degree of crystallinity of PHB and flame retardance effect of TM.
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Affiliation(s)
- Huimin Ma
- Tianjin Key Laboratory of Hazardous Waste Safety Disposal and Recycling Technology, School of Environmental Science and Safety Engineering, Tianjin University of Technology, 391 Binshui Xidao, Xiqing District, Tianjin 300384, China
| | - Ziyu Wei
- Tianjin Key Laboratory of Hazardous Waste Safety Disposal and Recycling Technology, School of Environmental Science and Safety Engineering, Tianjin University of Technology, 391 Binshui Xidao, Xiqing District, Tianjin 300384, China; CAS Center for Excellence in Nanoscience, CAS Key Laboratory for Biological Effects of Nanomaterials and Nanosafety, National Center for Nanoscience and Technology (NCNST), No. 11 Beiyitiao, Zhongguancun, Beijing 100190, China
| | - Shanshan Zhou
- Tianjin Key Laboratory of Hazardous Waste Safety Disposal and Recycling Technology, School of Environmental Science and Safety Engineering, Tianjin University of Technology, 391 Binshui Xidao, Xiqing District, Tianjin 300384, China
| | - Haibo Zhu
- Tianjin Key Laboratory of Hazardous Waste Safety Disposal and Recycling Technology, School of Environmental Science and Safety Engineering, Tianjin University of Technology, 391 Binshui Xidao, Xiqing District, Tianjin 300384, China; Tianjin Fire Research Institute of the Ministry of Emergency Management, Tianjin 300381, China
| | - Jingjing Tang
- Tianjin Key Laboratory of Hazardous Waste Safety Disposal and Recycling Technology, School of Environmental Science and Safety Engineering, Tianjin University of Technology, 391 Binshui Xidao, Xiqing District, Tianjin 300384, China
| | - Jing Yin
- Tianjin Key Laboratory of Hazardous Waste Safety Disposal and Recycling Technology, School of Environmental Science and Safety Engineering, Tianjin University of Technology, 391 Binshui Xidao, Xiqing District, Tianjin 300384, China
| | - Junjie Yue
- Tianjin Key Laboratory of Hazardous Waste Safety Disposal and Recycling Technology, School of Environmental Science and Safety Engineering, Tianjin University of Technology, 391 Binshui Xidao, Xiqing District, Tianjin 300384, China.
| | - Jinjun Yang
- Tianjin Key Laboratory of Hazardous Waste Safety Disposal and Recycling Technology, School of Environmental Science and Safety Engineering, Tianjin University of Technology, 391 Binshui Xidao, Xiqing District, Tianjin 300384, China.
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Kang EY, Park SB, Choi B, Baek SW, Ko KW, Rhim WK, Park W, Kim IH, Han DK. Enhanced mechanical and biological characteristics of PLLA composites through surface grafting of oligolactide on magnesium hydroxide nanoparticles. Biomater Sci 2020; 8:2018-2030. [PMID: 32080689 DOI: 10.1039/c9bm01863h] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Poly(l-lactic acid) (PLLA) is a biocompatible and biodegradable polymer that has received much attention as a biomedical material. However, PLLA also produces by-products that acidify the surrounding tissues during in vivo degradation, which induces inflammatory responses. To overcome these problems, magnesium hydroxide nanoparticles (nano-magnesium hydroxide; nMH) were added to the PLLA matrix as a bioactive filler that can suppress inflammatory responses by neutralizing the acidified environment caused by the degradation of PLLA. Despite the advantages of nMH, the strong cohesion of these nanoparticles toward each other makes it difficult to manufacture a polymer matrix containing homogeneous nanoparticles through thermal processing. Here, we prepared two types of surface-modified nMH with oligolactide (ODLLA) utilizing grafting to (GT) and grafting from (GF) strategies to improve the mechanical and biological characteristics of the organic-inorganic hybrid composite. The incorporation of surface-modified nMH not only enhanced mechanical properties, such as Young's modulus, but also improved homogeneity of magnesium hydroxide particles in the PLLA matrix due to the increase in interfacial interaction. Additionally, the PLLA composites with surface-modified nMH exhibited reduced bulk erosion during hydrolytic degradation with lower cytotoxicity and immunogenicity. Hemocompatibility tests on the PLLA composites with nMH showed a higher albumin to fibrinogen ratio (AFR) and a lower influence of platelet activation, when compared with unmodified control samples. Taken all together, the surface-modified nMH could be seen to successfully improve the physical and biological characteristics of polymer composites. We believe this technology has great potential for the development of hybrid nanocomposites for biomedical devices, including cardiovascular implants.
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Affiliation(s)
- Eun Young Kang
- Department of Biomedical Science, CHA University, 335 Pangyo-ro, Bundang-gu, Seongnam-si, Gyeonggi 13488, Republic of Korea. and Department of Biological Science, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul 02841, Republic of Korea
| | - Sung-Bin Park
- Department of Biomedical Science, CHA University, 335 Pangyo-ro, Bundang-gu, Seongnam-si, Gyeonggi 13488, Republic of Korea.
| | - Bogyu Choi
- Department of Biomedical Science, CHA University, 335 Pangyo-ro, Bundang-gu, Seongnam-si, Gyeonggi 13488, Republic of Korea.
| | - Seung-Woon Baek
- Department of Biomedical Science, CHA University, 335 Pangyo-ro, Bundang-gu, Seongnam-si, Gyeonggi 13488, Republic of Korea. and Department of Biomedical Engineering, Sungkyunkwan University, 2066 Seobu-ro, Jangan-gu, Gyeonggi-do 16419, Republic of Korea
| | - Kyoung-Won Ko
- Department of Biomedical Science, CHA University, 335 Pangyo-ro, Bundang-gu, Seongnam-si, Gyeonggi 13488, Republic of Korea.
| | - Won-Kyu Rhim
- Department of Biomedical Science, CHA University, 335 Pangyo-ro, Bundang-gu, Seongnam-si, Gyeonggi 13488, Republic of Korea.
| | - Wooram Park
- Department of Biomedical Science, CHA University, 335 Pangyo-ro, Bundang-gu, Seongnam-si, Gyeonggi 13488, Republic of Korea.
| | - Ik-Hwan Kim
- Department of Biological Science, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul 02841, Republic of Korea
| | - Dong Keun Han
- Department of Biomedical Science, CHA University, 335 Pangyo-ro, Bundang-gu, Seongnam-si, Gyeonggi 13488, Republic of Korea.
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Effects of Magnesium Oxide (MgO) Shapes on In Vitro and In Vivo Degradation Behaviors of PLA/MgO Composites in Long Term. Polymers (Basel) 2020; 12:polym12051074. [PMID: 32397097 PMCID: PMC7284841 DOI: 10.3390/polym12051074] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 04/27/2020] [Accepted: 04/28/2020] [Indexed: 11/17/2022] Open
Abstract
Biodegradable devices for medical applications should be with an appropriate degradation rate for satisfying the various requirements of bone healing. In this study, composite materials of polylactic acid (PLA)/stearic acid-modified magnesium oxide (MgO) with a 1 wt% were prepared through blending extrusion, and the effects of the MgO shapes on the composites’ properties in in vitro and in vivo degradation were investigated. The results showed that the long-term degradation behaviors of the composite samples depended significantly on the filler shape. The degradation of the composites is accelerated by the increase in the water uptake rate of the PLA matrix and the composite containing the MgO nanoparticles was influenced more severely by the enhanced hydrophilicity. Furthermore, the pH value of the phosphate buffer solution (PBS) was obviously regulated by the dissolution of MgO through the neutralization of the acidic product of the PLA degradation. In addition, the improvement of the in vivo degrading process of the composite illustrated that the PLA/MgO materials can effectively regulate the degradation of the PLA matrix as well as raise its bioactivity, indicating the composites for utilization as a biomedical material matching the different requirements for bone-related repair.
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Shuai C, Zan J, Yang Y, Peng S, Yang W, Qi F, Shen L, Tian Z. Surface modification enhances interfacial bonding in PLLA/MgO bone scaffold. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2020; 108:110486. [DOI: 10.1016/j.msec.2019.110486] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2019] [Revised: 11/11/2019] [Accepted: 11/22/2019] [Indexed: 12/18/2022]
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Lei XX, Lu H, Lu L, Xu HQ, Zhou YG, Zou J. Improving the Thermal and Mechanical Properties of Poly(l-lactide) by Forming Nanocomposites with an in Situ Ring-Opening Intermediate of Poly(l-lactide) and Polyhedral Oligomeric Silsesquioxane. NANOMATERIALS 2019; 9:nano9050748. [PMID: 31096704 PMCID: PMC6566323 DOI: 10.3390/nano9050748] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/31/2019] [Revised: 05/04/2019] [Accepted: 05/13/2019] [Indexed: 12/13/2022]
Abstract
In this study, a series of poly(l-lactide) and (3-amino)-propylheptaisobutyl cage silsesquioxane (PLLA-AMPOSS) intermediates were first fabricated using single-arm in situ solution polymerization of LLA monomers and AMPOSS nanoparticles with different contents, 0.02-1.00 mol%. Then, the PLLA-AMPOSS intermediate with 0.5 mol% AMPOSS was selected as a representative and investigated by nuclear magnetic resonance (NMR) and X-ray diffraction (XRD). Afterwards, it was added into the pure PLLA with different mass fractions. Finally, the thermal behavior, crystallization kinetics, morphological characteristics, and mechanical properties of the obtained PLLA/PLLA-AMPOSS nanocomposites were carefully measured and investigated by differential scanning calorimetry (DSC), polarizing microscopy (POM), scanning electron microscopy (SEM), and tensile test. After comparing the PLLA-AMPOSS intermediate and PLLA/AMPOSS blend, the results show that the ring-open polymerization of PLLA-AMPOSS intermediate was successful. The results also show that the existence of PLLA-AMPOSS has a strong influence on the crystallization behavior of PLLA/PLLA-AMPOSS composites, which can be attributed to the heterogeneous nucleation effect of PLLA-AMPOSS. In addition, it was also found from the tensile test results that the addition of the PLLA-AMPOSS nanofiller improved the tensile strength and strain at break of PLLA/PLLA-AMPOSS nanocomposites. All of these results indicate the good nucleating effect of PLLA-AMPOSS and that the AMPOSS disperses well in the PLLA/PLLA-AMPOSS nanocomposites. A conclusion can be drawn that the selective nucleating agent and the combined method of in situ ring-opening polymerization and physical blending are feasible and effective.
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Affiliation(s)
- Xiu-Xiu Lei
- School of Materials Science and Engineering, Jiangsu University of Science and Technology, Zhenjiang 212003, China.
| | - Hao Lu
- School of Materials Science and Engineering, Jiangsu University of Science and Technology, Zhenjiang 212003, China.
| | - Lei Lu
- School of Materials Science and Engineering, Jiangsu University of Science and Technology, Zhenjiang 212003, China.
| | - Hai-Qing Xu
- Jiangsu Provincial Engineering Laboratory for Advanced Materials of Salt Chemical Industry, Huaiyin Institute of Technology, Huai'an 223003, China.
| | - Ying-Guo Zhou
- School of Materials Science and Engineering, Jiangsu University of Science and Technology, Zhenjiang 212003, China.
| | - Jun Zou
- School of Materials Science and Engineering, Jiangsu University of Science and Technology, Zhenjiang 212003, China.
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Zhao Y, Liu B, Bi H, Yang J, Li W, Liang H, Liang Y, Jia Z, Shi S, Chen M. The Degradation Properties of MgO Whiskers/PLLA Composite In Vitro. Int J Mol Sci 2018; 19:E2740. [PMID: 30217013 PMCID: PMC6165512 DOI: 10.3390/ijms19092740] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2018] [Revised: 08/28/2018] [Accepted: 08/30/2018] [Indexed: 11/24/2022] Open
Abstract
In this study, composite films of stearic acid⁻modified magnesium oxide whiskers (Sa⁻w-MgO)/poly-l-lactic acid (PLLA) were prepared through solution casting, and the in vitro degradation properties and cytocompatibility of the composites with different whisker contents were investigated. The results showed that the degradation behavior of the composite samples depended significantly on the whisker content, and the degradation rate increased with the addition of MgO content. Furthermore, the degradation of the composites with higher contents of whiskers was influenced more severely by the hydrophilicity and pH value, leading to more final weight loss, but the decomposition rate decreased gradually. Furthermore, the pH value of the phosphate buffer solution (PBS) was obviously regulated by the dissolution of MgO whiskers through neutralization of the acidic product of PLLA degradation. The cytocompatibility of the composites also increased remarkably, as determined from the cell viability results, and was higher than that of PLLA at the chosen whisker content. This was beneficial for the cell affinity of the material, as it notably led to an enhanced biocompatibility of the PLLA, in favor of promoting cell proliferation, which significantly improved its bioactivity, as well.
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Affiliation(s)
- Yun Zhao
- School of Materials Science and Engineering, Tianjin University of Technology, Tianjin 300384, China.
- Key Laboratory of Display Materials and Photoelectric Device (Ministry of Education), Tianjin University of Technology, Tianjin 300384, China.
| | - Bei Liu
- School of Materials Science and Engineering, Tianjin University of Technology, Tianjin 300384, China.
| | - Hongwei Bi
- Tianjin Sannie Bioengineering Technology Co., Ltd., Tianjin 300384, China.
| | - Jinjun Yang
- School of Environmental Science and Safety Engineering, Tianjin University of Technology, Tianjin 300384, China.
| | - Wei Li
- School of Materials Science and Engineering, Tianjin University of Technology, Tianjin 300384, China.
- Key Laboratory of Display Materials and Photoelectric Device (Ministry of Education), Tianjin University of Technology, Tianjin 300384, China.
| | - Hui Liang
- School of Materials Science and Engineering, Tianjin University of Technology, Tianjin 300384, China.
| | - Yue Liang
- School of Materials Science and Engineering, Tianjin University of Technology, Tianjin 300384, China.
| | - Zhibin Jia
- School of Materials Science and Engineering, Tianjin University of Technology, Tianjin 300384, China.
| | - Shuxin Shi
- School of Materials Science and Engineering, Tianjin University of Technology, Tianjin 300384, China.
| | - Minfang Chen
- School of Materials Science and Engineering, Tianjin University of Technology, Tianjin 300384, China.
- Key Laboratory of Display Materials and Photoelectric Device (Ministry of Education), Tianjin University of Technology, Tianjin 300384, China.
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Polycondensation of a Perylene Bisimide Derivative and L-Malic Acid as Water-Soluble Conjugates for Fluorescent Labeling of Live Mammalian Cells. Polymers (Basel) 2018; 10:polym10050559. [PMID: 30966593 PMCID: PMC6415357 DOI: 10.3390/polym10050559] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2018] [Revised: 05/16/2018] [Accepted: 05/22/2018] [Indexed: 12/23/2022] Open
Abstract
Based on simple mixing and polymerization of a hydroxyl-containing derivative of perylene bisimide (PBI) and l-malic acid, here, we demonstrate a new type of dye-polymer conjugate, PBI-poly(α,β-malic acid) (PBI–PMA). Benefiting from the excellent water-solubility of weak polyanionic PMA structure and the high fluorescence of PBI, the PBI-PMA conjugates readily dissolve in water, displaying strong pH-dependent fluorescence with the highest intensity at pH 6. Due to the excellent biocompatibility of PMA, those conjugates showed low cytotoxicity on L929 cells. Using L929 and HeLa cells, we also confirmed that the PBI-PMA-labeled cells display intense fluorescence. Overall, the PBI-PMA conjugate demonstrates high potential as a cell labeling agent with its synthesis ease, good solubility in aqueous medium, low cytotoxicity, and high fluorescence.
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Ge M, Ge K, Gao F, Yan W, Liu H, Xue L, Jin Y, Ma H, Zhang J. Biomimetic mineralized strontium-doped hydroxyapatite on porous poly(l-lactic acid) scaffolds for bone defect repair. Int J Nanomedicine 2018; 13:1707-1721. [PMID: 29599615 PMCID: PMC5866725 DOI: 10.2147/ijn.s154605] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Introduction poly(l-lactic acid) (PLLA) has been approved for clinical use by the US Food and Drug Administration (FDA); however, their stronger hydrophobicity and relatively fast degradation rate restricted their widespread application. In consideration of the composition of bone, the inorganic–organic composite has a great application prospect in bone tissue engineering. Many inorganic–organic composite scaffolds were prepared by directly mixing the active ingredient, but this method is uncontrolled and will lead to lack of homogeneity in the polymer matrix. Strontium (Sr) is an admirable addition to improve the bioactivity and bone induction of hydroxyapatite (HA). To our knowledge, the application of biomimetic mineralized strontium-doped hydroxyapatite on porous poly(l-lactic acid) (Sr-HA/PLLA) scaffolds for bone defect repair has never been reported till date. Biomimetic mineralized Sr-HA/PLLA porous scaffold was developed in this study. The results indicated that the Sr-HA/PLLA porous scaffold could improve the surface hydrophobicity, reduce the acidic environment of the degradation, and enhance the osteoinductivity; moreover, the ability of protein adsorption and the modulus of compression were increased. The results also clearly showed the effectiveness of the Sr-HA/PLLA porous scaffold in promoting cell adhesion, proliferation, and alkaline phosphatase (ALP) activity. The micro computed tomography (micro-CT) results showed that more new bones were formed by Sr-HA/PLLA porous scaffold treatment. The histological results confirmed the osteoinductivity of the Sr-HA/PLLA porous scaffold. The results suggested that the Sr-HA/PLLA porous scaffold has a good application prospect in bone tissue engineering in the future. Purpose The purpose of this study was to promote the bone repair. Materials and methods Surgical operation of rabbits was carried out in this study. Results The results showed that formation of a large number of new bones by the Sr-HA/PLLA porous scaffold treatment is possible. Conclusion Biomimetic mineralized Sr-HA/PLLA porous scaffold could effectively promote the restoration of bone defects in vivo.
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Affiliation(s)
- Min Ge
- Department of Chemistry, College of Chemistry and Environmental Science, Hebei University, Baoding, People's Republic of China.,Key Laboratory of Chemical Biology of Hebei Province, Key Laboratory of Medicinal Chemistry and Molecular Diagnosis of the Ministry of Education, Hebei University, Baoding, People's Republic of China
| | - Kun Ge
- Department of Chemistry, College of Chemistry and Environmental Science, Hebei University, Baoding, People's Republic of China.,Department of Science and Technology, Affiliated Hospital of Hebei University, Baoding, People's Republic of China
| | - Fei Gao
- Department of Orthopedics, Affiliated Hospital of Hebei University, Baoding, People's Republic of China
| | - Weixiao Yan
- Department of Chemistry, College of Chemistry and Environmental Science, Hebei University, Baoding, People's Republic of China.,Key Laboratory of Chemical Biology of Hebei Province, Key Laboratory of Medicinal Chemistry and Molecular Diagnosis of the Ministry of Education, Hebei University, Baoding, People's Republic of China
| | - Huifang Liu
- Key Laboratory of Chemical Biology of Hebei Province, Key Laboratory of Medicinal Chemistry and Molecular Diagnosis of the Ministry of Education, Hebei University, Baoding, People's Republic of China
| | - Li Xue
- Department of Chemistry, College of Chemistry and Environmental Science, Hebei University, Baoding, People's Republic of China
| | - Yi Jin
- Department of Chemistry, College of Chemistry and Environmental Science, Hebei University, Baoding, People's Republic of China.,Key Laboratory of Chemical Biology of Hebei Province, Key Laboratory of Medicinal Chemistry and Molecular Diagnosis of the Ministry of Education, Hebei University, Baoding, People's Republic of China
| | - Haiyun Ma
- Department of Chemistry, College of Chemistry and Environmental Science, Hebei University, Baoding, People's Republic of China
| | - Jinchao Zhang
- Department of Chemistry, College of Chemistry and Environmental Science, Hebei University, Baoding, People's Republic of China.,Key Laboratory of Chemical Biology of Hebei Province, Key Laboratory of Medicinal Chemistry and Molecular Diagnosis of the Ministry of Education, Hebei University, Baoding, People's Republic of China
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