BIOMACROMOLECULES
·
2020
·
IF 6.092
Zuowen Shi,Xu Zhang,Xiaodan Wang,Fangping Yang,Zikun Yu,Ying Ling,Hua Lu,Shifang Luan,Haoyu Tang
A series of cationic polypeptide imidazolium conjugates were prepared by ring-opening polymerization (ROP) of γ-4-(3-chloropropoxycarbonyl)benzyl-L- glutamic acid-based N-carboxyanhydride (CPBLG-NCA) initiated by various mono- or diamine initiators and subsequent side-chain modification with high grafting efficiency. Rapid and controlled ROP was achieved by polymerizing CPBLG-NCA in a dichloromethane/NaHCO3/H2O solvent mixture with the amine initiators. The resulting polypeptides bearing imidazolium iodide pendants showed reversible upper critical solution temperature (UCST)-type thermoresponsive properties in both ethanol and DI water while the polypeptides with tetrafluoroborate counter-anions showed a UCST in phosphate buffer saline (PBS). The cloud point temperature (Tcp) in ethanol and aqueous solutions can be tuned by both molecular weight and the end- or linkage-groups in the main chain. The cationic polypeptides showed good antibacterial activity against Staphylococcus aureus and low hemolysis. Our results provide a facile and rapid ROP strategy to develop new families of stimuli-responsive polypeptides with tunable properties as well as antibacterial polypeptides with optimized selectivity.
研究领域:
高分子化学
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生物材料科学
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有机合成
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产品关联
DOI
PubMed
高影响因子
Science China-Chemistry
·
2013
·Vol. 56
·期 6
·729-738
·
IF 1.327
Han JinDong,Ding JianXun,Wang ZhiChun,Yan ShiFeng,Zhuang XiuLi,Chen XueSi,Yin JingBo
Diethylamine, di- n -hexylamine, dicyclohexylamine and triethylamine have been used as initiators for the ring-opening polymerization of γ-benzyl- l -glutamate N -carboxyanhydride (BLG NCA) to synthesize poly(γ-benzyl- l -glutamate) (PBLG). The relationship between the molecular weight of PBLG and the molar ratio of monomer and initiator was studied. With dicyclohexylamine as initiator, the influence of monomer concentration, and reaction temperature and time on the polymerization of BLG NCA was examined. Three reagents were used for the deprotection of benzyl groups in PBLG, including hydrobromic acid/acetic acid (33 wt.%), NaOH aqueous solution and trimethylsilyl iodide (TMSI). Through examining the molecular weight of PLGA obtained using different deprotection methods, it was revealed that TMSI could minimize chain cleavage in the process of deprotection and retain the degree of polymerization. The biocompatibilities of PBLG obtained using different initiators were evaluated by a live/dead assay against L929 fibroblast cells. The in vitro cytotoxicities of PLGA obtained using different deprotecting agents were evaluated by a methyl thiazolyl tetrazolium assay. The results revealed that both PBLG and PLGA exhibited good biocompatibilities.
研究领域:
高分子化学
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生物材料学
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细胞生物学
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DOI
高影响因子
MACROMOLECULES
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2023
·
IF 5.5
Xinyan Yu,Yong Wang,Yutong Dong,Ning Zhao,Lifeng Zhang,Sunting Xuan,Zhengbiao Zhang
N-Methyl peptides, which are widely found in nature, have emerged as an intriguing material in both polymer science and the biomedical field. The inefficient synthesis of N-methyl peptides, however, has greatly impeded the progress toward their structure–property investigation and applications. Here, we report an efficient, moisture-tolerant, primary amine-initiated, and acetic acid-catalyzed ring-opening polymerization of enantiomerically pure N-methyl-α-amino acids N-carboxyanhydrides, yielding well-defined, stereoregular, and structurally diverse N-methyl polypeptides. The concentration of the acetic acid, polarity of solvents, and stiffness of polymer chains were found to be crucial to the rate of the polymerization. The acetic acid was proposed to activate the monomer through hydrogen bonding interaction, promote the release of CO2, and form an acid–base equilibrium with the secondary amine chain end. The obtained N-methyl polypeptides exhibited stable helix structures, revealing chain stiffness, consistent with the high glass transition temperatures (>250 °C) from DSC measurements. Moreover, preliminary studies indicated that N-methyl polypeptides are nontoxic both in vitro and in vivo and are enzymatically stable toward trypsin treatment. Together, this study provides a mild and efficient method for the preparation of N-methyl polypeptides, opening avenues for their further structure–property investigation and potential applications.
研究领域:
高分子科学
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生物医学领域
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材料科学
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有机化学
✓ 已验证
产品关联
DOI
高影响因子
BIOMACROMOLECULES
·
2024
·
IF 5.5
Xiao Sun,Aoting Li,Ning Li,Guonan Ji,Ziyuan Song
Heteropolypeptides bearing two or more functional side chains are promising polymeric materials for various biomedical applications. However, conventional preparation of heteropolypeptides relies on the synthesis and purification of each N-carboxyanhydride (NCA) monomer in a separate manner, which substantially increases the time and cost. Herein, we report the facile preparation of heteropolypeptides with up to 86% yield within several hours, which are obtained from a mixture of crude NCA monomers. The combination of n-hexane precipitation and biphasic segregation effectively removed >90% impurities from crude NCA mixtures, allowing for the successful polymerization process. Various heteropolypeptides with monomodal distribution and narrow dispersity were efficiently prepared, whose compositions were predetermined by the feeding ratios of amino acids. We believe that this work significantly simplifies the preparation of various heteropolypeptides, boosting the downstream studies of these promising materials.
研究领域:
高分子科学
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材料科学
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生物技术
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化学工程
✓ 已验证
DOI
PubMed
高影响因子
EUROPEAN POLYMER JOURNAL
·
2022
·
IF 5.546
Feiyi Zhang,Lanlan Yu,Zhun Deng,Shuli Liu,Chenxuan Wang,Lei Liu
A variety of natural proteins have shown anti-adhesive functionality against the non-specific adsorption by proteins and bacteria. A deep understanding of the contribution of amino acid composition to the antifouling performance of a natural protein is crucial for engineering a protein-based coating layer. Herein, we synthesized five types of homo poly(amino acid)s via the ring-opening polymerization of α-amino acid N -carboxy anhydride (NCA) to include exclusively one type of amino acid from lysine (K), glutamic acid (E), tyrosine (Y), alanine (A), and phenylalanine (F). Homo poly(amino acid)s were covalently immobilized on the surfaces of quartz and polyurethane (PU), respectively. The amino acid composition effects on the wetting and anti-bacterial adhesion of a homo poly(amino acid) coating layer were evaluated. We found that the wettability of homo poly(amino acid) coating layers exhibited a dependence on the intrinsic properties of amino acid side-chain, such as the hydration free energy and dipole moment of side-chain. The activity of a homo poly(amino acid) coating layer against bacterial adsorption was found to be independent of the wetting property of the amino acid side-chain. Our findings are different from the conventional opinion that the hydration property of a material surface coating layer correlates to its anti-bacterial functionality, emphasizing the complexity of the amino acid composition contribution to the activity against the non-specific adsorption of bacteria for a protein-mimicking system.
研究领域:
材料科学
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生物材料
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生物物理学
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高分子化学
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微生物学
✓ 已验证
DOI
高影响因子
Biomaterials Science
·
2019
·Vol. 7
·期 9
·3675-3682
·
IF 5.251
Bing Li,Yueming Wu,Wenjing Zhang,Si Zhang,Ning Shao,Weiwei Zhang,Lixin Zhang,Jian Fei,Yidong Dai,Runhui Liu
Proteins are fragile such that even freezing, drying and dehydration may induce their denaturation, aggregation, and activity loss. To protect proteins from these kinds of damage, we prepared two types of amino acid polymers, poly-(L-glutamate)-r-poly-(L-lysine) (PLG-r-PLL) and poly-L-glutamate (PLG), from the efficient ring-opening polymerization of α-amino acid N-carboxyanhydride (NCA) using lithium hexamethyldisilazide (LiHMDS) as the initiator. β-galactosidase (β-Gal) was used in this study to examine the protein protecting effect of the synthesized amino acid polymers during lyophilization. The results indicate that both PLG-r-PLL and PLG exert significant protection on β-Gal during lyophilization and improve the activity of the resulting protein from 40%, without using a protecting agent during lyophilization, to 80% of the original protein activity. Nevertheless, PLG generally performs better than PLG-r-PLL independent of the chain length. Our studies also show that PLG and PLG-r-PLL with a high content of PLG subunits display no observable cytotoxicity and hemolytic effect. Furthermore, dynamic light scattering (DLS) and transmission electron microscopy (TEM) characterization indicate that PLG protects β-Gal upon lyophilization by preventing the aggregation of β-Gal. Our studies demonstrate that amino acid polymers, such as PLG, can exert potent activity for protein stabilization. The easy operation of LiHMDS-initiated and efficient NCA polymerization implies the great potential of this strategy to prepare amino acid polymers quickly for the screening of protein stabilization and mechanism study.
研究领域:
聚合物化学
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生物技术
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药学
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蛋白质工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
BIOMACROMOLECULES
·
2021
·
IF 6.988
Shuai Zhu,Ruizhong Xue,Zikun Yu,Xu Zhang,Shifang Luan,Haoyu Tang
Poly(l-cysteine)s with methylthio pendants (PMTLCs) were synthesized by ring-opening polymerization of a new l-cysteine-based N-carboxyanhydride. The thioether bonds of PMTLC can be readily oxidized by H2O2 yielding water-soluble PMTLCOX. The methylthio groups can undergo an alkylation reaction using methyl iodide and a subsequent ion-exchange reaction yielding sulfonium-based polypeptides (PPLC-DMS-X, where X = I, BF4). PPLC-DMS-X showed upper critical solution temperature-type thermo- and oxidation-responsive properties in aqueous solutions. Both PMTLC and PPLC-DMS-X showed oxidation-induced β-sheet to α-helix transitions. The absorbance of PPLC-DMS-I and methyl orange aqueous solution displayed a significant linear correlation with temperature, which makes the sulfonium-based polypeptides good candidates in the field of temperature sensors.
研究领域:
高分子化学
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材料科学
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物理化学
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分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Biomaterials Science
·
2021
·Vol. 10
·期 3
·834-845
·
IF 6.843
Xiaodan Wang,Fangping Yang,Huawei Yang,Xu Zhang,Haoyu Tang,Shifang Luan
Antimicrobial peptides (AMPs) are attractive antimicrobial agents used to combat bacterial infections, and have been advanced to be one of the most promising alternatives to conventional antibiotics. They stand out for their attractive broad-spectrum activity, unmatched antibacterial mechanism that is not prone to develop drug resistance and diversified topologies, which can be fabricated with manifold amino acid blocks. In this study, using n-hexylamine and amine-terminated polyamidoamine dendrimers (Gx-PAMAM, x = 1–2) as initiators, a series of AMPs with linear and star-shaped topological structures were constructed via the controllable ring-opening polymerization (ROP) of N-carboxyanhydrides (NCAs). The antibacterial performances of the tailored linear and star-shaped AMPs were comprehensively evaluated in both solution states and surface-bonded states. The results indicated that the star-shaped AMPs exhibited enhanced bactericidal activity against Gram-negative E. coli and similar bactericidal activity against Gram-positive S. aureus when compared with the linear AMPs. It is worth mentioning that star-shaped AMPs demonstrated a significantly faster bactericidal efficiency (completely killed bacteria within 5 min at a concentration of 2 × MIC for S. aureus) than their linear analogues (took 15 min to achieve the same effect). However, when the AMPs were immobilized to the surface, they similarly exhibited superior antibacterial activity and fast bactericidal efficiency towards S. aureus and E. coli in the case of the same surface grafting amount. In addition, both the surfaces grafted with AMPs of different topologies demonstrated favorable biocompatibility in vitro.
研究领域:
生物材料
·
生物技术
·
微生物学
·
高分子化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）