Polymers
·
2020
·Vol. 12
·期 9
·2053
·
IF 3.426
Chen Qi,Wenke Yang,Fuyan He,Jinshui Yao
Eight kinds of chiral diacid monomers were prepared with amino acids with different side groups or configurations. Polyester-imides (PEIs) were synthesized from these diacid monomers and diphenol monomers through polycondensation reaction, and the performances and properties were compared with the chiral polyamide-imides (PAIs) previously synthesized by our work group. Their thermal properties were analyzed by thermo gravimetric analysis (TGA) and dynamic thermomechanical analysis (DMA), and it was found that the glass transition temperature (Tg) of PEI was mainly affected by the volume of side groups. Their degradability was studied through buffer degradation experiments, and the changes in their water contact angle, molecular weight, structure and appearance during the degradation process were characterized by contact angle tester, gel permeation chromatography (GPC), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). With degradation, the hydrophilicity of PEI was improved, and when amino acids with larger side groups or D configuration were introduced into the backbone of PEI, the degradability decreased.Keywords:chiral amino acids;polyester-imides (PEIs);degradation;thermal property
研究领域:
材料科学
·
生物医学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Polymers
·
2020
·Vol. 12
·期 9
·2164
·
IF 3.426
Xinqiang Xu,Fuyan He,Wenke Yang,Jinshui Yao
As natural polymer materials, proteins are readily biodegradable, interestingly, the synthetic polyamides (PAs) that are based on the same amide bonds (also called peptide bonds in proteins) are barely degradable. Whether did the chirality and configuration of the amino acids play an important role. By using different configuration of amino acids, 4 types of polyamide-imides (PAIs) containing dipeptides ofLL,DL,LD, and DD configurations, respectively, were synthesized. It was found that the PAIs based on naturalLLconfiguration of dipeptide structure are much more readily biodegradable than those based on non-naturalLD,DL,andDDconfiguration of dipeptides. It was confirmed that the naturalL-configuration of amino acids play a critical role in degradability of proteins. And it also suggested that different type and amount of peptide fragments can be introduced in polymer to create series of polymer materials that can be biodegraded at controllable speed.Keywords:chiral amino acids;dipeptide;polyamide-imides;biodegradability
研究领域:
生物化学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
REACTIVE & FUNCTIONAL POLYMERS
·
2014
·
IF 2.822
Xiaohai Bu,Yuming Zhou,Zhenjie Chen,Man He,Tao Zhang
Chiral amino acid-based monosubstituted acetylene monomers [ N - tert -butoxy-carbonyl- l -phenylalanine- N ′-propargylamide (LP), and N - tert -butoxycarbonyl- l -serine- N ′-propargylamide (LS)] were (co)polymerized with rhodium zwitterion catalyst in THF to afford helical polyacetylenes (PAs) with moderate molecular weights (4400–14,800) in good yields. The optically active PA copolymers were soluble in common organic solvents and proven to adopt predominately single-handed helical conformations according to their intense Cotton effect and large specific rotations. Various contents of amino acid units in side chains facilitated controllable helical secondary structure while the helix was primarily stabilized by hydrogen bonding and steric repulsion between the substituents. Intramolecular hydrogen bonds constructed between hydroxyl and amide groups, in particular, played a significant role in adjusting the helicity and orderliness of the helix. The infrared emissivity values of the PAs at wavelength of 8–14 μm were measured and the correlation between helical conformations and their effect on infrared emission were systematically investigated. The results showed that more well-ordered and compact screw-sense could enhance the performance of organic polymers in lowering their infrared emissivity. Among all the as-prepared PAs, poly(LP 50 - co -LS 50 ) exhibited the lowest infrared emissivity value ( ε 25 = 0.632) and possessed excellent resistance against heat.
研究领域:
高分子化学
·
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2019
·
IF 4.784
Jie Zhang,Jihong Hu,Datong Wu,Jianfeng Ma,Yongxin Tao,Yong Qin,Yong Kong
Sodium alginate (SA) was electrodeposited onto the surface of a glassy carbon electrode (GCE), and then l -lysine ( l -Lys), l -alanine ( l -Ala) and l -cysteine ( l -Cys) were simultaneously introduced to the surface of SA via electrostatic attractions. γ-MnO 2 film was deposited potentiostatically onto the multi-templates immobilized SA from an aqueous mixture of K 2 SO 4 and MnSO 4 . The templates of l -Lys, l -Ala and l -Cys were then oxidized and removed by cyclic voltammetry (CV) while maintaining the crystalline structures of SA and MnO 2 . Finally, the molecularly imprinted SA/MnO 2 was successfully applied in the simultaneous recognition of the isomers of Lys, Ala and Cys by differential pulse voltammetry (DPV). This work opens a new avenue in the construction of SA-based multi-templates molecularly imprinted systems for electrochemical simultaneous recognition of the isomers of several chiral amino acids .
研究领域:
生物化学
·
材料科学
·
分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Magnetic Resonance Open
·
2025
·
IF 2
Bowen Han,Jing He,Shaohua Huang
Chiral amino acids play an indispensable role in living organisms. Diffusion-ordered NMR spectroscopy is an effective NMR tool and a noninvasive analytical method for the analyses of mixture without the need for physical separation of the analytes. However, conventional diffusion-ordered NMR spectroscopy method usually fails to resolve the mixtures of chiral amino acids because of their same molecular masses, sizes, and shapes. Microcrystalline cellulose has been gradually gained more and more interest owing to its wide compatibility, surface area, excellent separation efficiency, non-toxicity, cost-effective, and mechanical stability in many fields. Herein we provide a fast, simple, specific and sensitive method to resolve some D and L-amino acids mixtures by using microcrystalline cellulose as a matrix. This work recognized some D and L- proteinogenic amino acid enantiomers with diffusion-ordered NMR for the first time.
研究领域:
分析化学
·
生物化学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry A
·
2024
·Vol. 12
·期 16
·9421-9426
·
IF 10.7
Yaxin Wang,Yajie Zhou,Shanshan Zhao,Mingjiang Zhang,Anqi Li,Guangen Li,Qi Guo,Xueru Guo,Zhi Tong,Zeyi Li,Jing Lin,Taotao Zhuang
Chiral amino acids are crucial for humans, and their recognition can provide information for pharmaceutical quality and clinical diagnosis. Histidine (His) and tryptophan (Trp), for example, have a close association with nephropathy and are extensively utilized in the pharmaceutical field. However, efficiently distinguishing these two amino acids and their configurations is still in its infancy, requiring the development of a practical, cost-effective, and reliable detection method. Herein, we disclose a dual-optical-response recognition system, composed of 9-aminoacridine and cellulose nanocrystals, that can stepwise recognize His/Trp and their enantiomers based on photoluminescence and circular dichroism (CD) analysis. Amino acids cause variation in the fluorescence intensity of the DOR system, while their enantiomers give distinctive shifts in CD spectra. This study achieves a stepwise recognition of chiral amino acids, paving a new way for drug screening and clinical diagnosis.
研究领域:
生物化学
·
药物分析
·
临床诊断
✓ 已验证
产品关联
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2023
·
IF 5.2
Man Zheng,Jiaxian Liu,Kun Shi,Yuxin Zhao,Tong Zhang,Fangxun Liu,Yidan Chen,Yuena Sun,Yufan Zhang,Huan Wang
In this study, we successfully prepared CH-CNT@Fe-Co-Pt x by combining chiral helical nanostructure , high conductivity, high electro-catalytic activity of iron-cobalt transition metals and precious platinum. The material used C 18 - L -Clu as the soft template, polypyrrole as the carbon source and nitrogen source. The precursor cobalt iron ions were then loaded onto the chiral amino acid template. Using the displacement reaction, a spot of platinum metal was successfully introduced into the composite to obtain CH-CNT@Fe-Co-Pt x composite material. According to the reaction mechanism steps of OER/ORR in alkaline solution, Fe-Co-Pt as the active site adsorbed OH - in OER and adsorbed H 2 O molecules in ORR. The tafer slope of OER and ORR for catalyst CH-CNT@Fe-Co-Pt 2 reached 35.0 mV dec −1 and 60.8 mV dec −1 , respectively. And the current density of H-CNT@Fe-Co-Pt 2 retained 84% and 91.5 % respectively after a long time i-t test. Moreover, the number of transferred electrons of CH-CNT@Fe-Co-Pt 2 in the ORR reaction reaches 3.90. This work provides new ideas for the research of chiral carbon nanomaterials in the field of electro-catalytic energy, and provides a new method for the development of efficient and low-cost energy electro-catalysts.
研究领域:
材料科学
·
电化学
·
纳米技术
·
能源材料
✓ 已验证
产品关联
DOI
高影响因子
PROTEIN EXPRESSION AND PURIFICATION
·
2024
·
IF 1.4
Junzhang Chang,Yuxin Zhang,Zhiwei Li,Yunfeng Ma,Xueqin Hu,Jingwen Yang,Hongbin Zhang
Chiral amino acids and their deamination products, α-keto acids, have important applications in food, medicine, and fine chemicals. In this study, two l -amino acid deaminase genes from Proteus mirabilis , PM473 of type Ⅰ and PM471 of type Ⅱ were cloned and expressed in Escherichia coli respectively, expected to achieve the chiral separation of amino acids . Extensive substrate preference testing showed that both deaminases had catalytic effects on the d -amino acid component of the D, l -amino acids, and PM473 has a wider catalytic range for amino acids. When D, L-Cys was used as the substrate, all L-Cys components and 75.1 % of D-Cys were converted to mercapto pyruvate , and the remaining D-Cys was a single chiral enantiomer . Molecular docking analysis showed that the interaction between the substrate and the key residues affected the stereoselectivity of enzymes . The compatibility of hydrophobicity between the binding pocket and substrate may be the basic factor that affects the substrate selectivity. This work provides an alternative method for the production of α-keto acids and the resolution of chiral amino acids.
研究领域:
生物化学
·
生物催化
·
酶学
·
药物化学
✓ 已验证
DOI
PubMed
高影响因子
Analytical Methods
·
2023
·Vol. 15
·期 7
·884-895
·
IF 3.1
Xin Wang,Xiaoqi Sun,Yueying Jin,Shengyu Cheng,Yu Han,Minghui Zhang,Lingli Zhang,Xi-Ling Li,Chun-Yan Xu,Jun Zhe Min
This study reports a novel fluorescent chiral derivatization reagent, 4-(N,N-dmethylaminosulfonyl)-2,1,3-benzoxadiazole-(2-succinimidoxy)-trans-2-methyl-L-proline (DBD-S-M-Pro), with a benzoxadiazole structure containing an N-hydroxysuccinimide activation group. DBD-S-M-Pro targets chiral amino-functional compounds under alkaline conditions without a condensation agent. Gradient elution was performed on a BEH C18 (100 × 2.1 mm, 1.7 μm) column with a mobile phase of 0.05% formic acid (FA) in 10 mM ammonium acetate (CH3COONH4) and 0.1% FA in acetonitrile or methanol. The efficiency of the chiral resolution was evaluated under excitation and emission wavelengths of 450 nm and 560 nm, respectively. The 19 chiral amino acids were separated in the range of 1.45–14.84. The resolutions of almost all DL-amino acids exceeded 1.5; the exceptions were serine (Ser) and lysine (Lys), with resolutions of 1.45 and 1.46, respectively. In addition, a new approach was devised for the simultaneous analysis of four chiral amino acids (DL-Glu, DL-Ala, DL-Val, and DL-Phe) in human hair. These amino acids were analyzed in the range of 12.5–400 pmol, with R2 ≥ 0.9990, limits of detection (S/N = 3) of 4–10 pmol, and intraday and interday precisions of 0.57–6.23%. The average spikes in the hair recoveries were 89.76–111.54%, and the matrix effects were 92.47–102.40%. Next, the contents of free chiral amino acids in the hair samples of 10 healthy volunteers (five males and five females) were analyzed with this method, and the differences were compared. The developed DBD-S-M-Pro provides a novel strategy for the sensitive determination of free chiral amino acids in living organisms.
研究领域:
分析化学
·
生物化学
·
药学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
·
2021
·
IF 9.229
Mengling Zhang,Yurong Ma,Huibo Wang,Bo Wang,Yunjie Zhou,Yang Liu,Mingwang Shao,Hui Huang,Fang Lu,Zhenhui Kang
Chiral carbon dots (CDs) integrated the advantages of achiral CDs and the unique chiral property, which expand the prospect of the biological applications of CDs. However, the structure control and the origin of chirality for chiral CDs remain unclear. Herein, chiral CDs were obtained by thermal polymerization of chiral amino acids and citric acid, and their handedness of chirality could be controlled by adjusting the reaction temperature, which leads to different kinds of surface modifications. With aliphatic amino acids as a chiral source, all of the CDs that reacted at different temperatures (90–200 °C) have the same handedness of the chiral source. But with aromatic amino acids as a chiral source, CDs with maintained or inversed handedness compared with the chiral source could be obtained by adjusting the reaction temperature. Below a temperature of 120 °C, the chiral source was modified with CDs by esterification and transferred the handedness of chirality; at high temperatures (above 150 °C), which mainly connected by amidation accompanying with the formation of rigid structure generated by the π conjugation between the aromatic nucleus of chiral source and the carbon core of CDs, caused the inversing of the chiral signal. Further, we investigated the chiral effects of CDs on the glucose oxidase activity for a highly sensitive electrochemical biosensor.
研究领域:
材料科学
·
纳米技术
·
生物技术
·
分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2019
·
IF 6.393
Qi Zhang,Mingxuan Fu,Haijun Lu,Xinyu Fan,Haiyang Wang,Yufan Zhang,Huan Wang
Novel chiral amino acids biosensor based on both potential difference and current ratio simultaneously was first established by employing left/right-handed double helix carbon nanotubes (L/D-DHCNT) with chiral structure as substrate material, and by self-assembly anchoring L/D-cysteine (L/D-Cys) on the surface of the left/right-handed double helix carbon nanotubes@Polypyrrole@Au nanoparticles nanocomposites (L/D-DHCNT@PPy@AuNPs). In this work, L/D-DHCNT@PPy@AuNPs@L/D-Cys was successfully constructed via a facile and environment-friendly process. Interestingly, in order to obtain highly dispersed AuNPs deposited on L/D-DHCNT, polypyrrole polymerized from pyrrole acts as a locating agent. Owing to the combination of unique performance of the L/D-Cys and L/D-DHCNT with chiral structure, and PPy and AuNPs with outstanding conductivity, an extremely efficient electrochemical chiral biosensing system was constructed that exhibited enhanced conductivity, sensitivity and chiral recognition capacity for tyrosine (Tyr), tryptophan (Trp) and glutamic acids (Glu) enantiomers. Utilizing both the potential difference and current ratio signal to commendably realize the electrochemical recognition and quantitative determination of amino acid enantiomers in their racemic solution. In addition, achieving the detection of Tyr in tablet samples by fabricated ultra-efficient electrochemical chiral biosensing system. Therefore, L/D-DHCNT@PPy@AuNPs@L/D-Cys as novel and ultrasensitive chiral biosensing system possesses the capability of chiral recognition of amino acid enantiomers, and it opens up the potential application of L/D-DHCNT@PPy@AuNPs@L/D-Cys in the field of chiral biosensors.
研究领域:
分析化学
·
纳米技术
·
生物传感器
·
电化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
ADVANCED SYNTHESIS & CATALYSIS
·
2022
·Vol. 364
·期 8
·1450-1459
·
IF 5.981
Feng Cheng,Jia-Min Zhang,Zhen-Tao Jiang,Xiao-Hu Wu,Ya-Ping Xue,Yu-Guo Zheng
Chiral amino acids are extensively applied in the pharmaceutical, food, cosmetic, and agricultural industries. As a representative example, l -phosphinothricin ( l -PPT, a chiral non-natural amino acid) is a broad-spectrum herbicide. An NAD(H)-driven biocatalytic system for the asymmetric synthesis of chiral amino acids (focused on l -PPT) with high efficiency and low cost is highly desired. The key for the development of such biocatalytic system is to obtain an NADH-dependent biocatalyst with high catalytic performance toward l -PPT pro-ketone PPO. Herein, an engineered glutamate dehydrogenase from Lysinibacillus composti ( Lc GluDH) with desired activity was obtained by gene mining and protein engineering. In silico analyses suggested that the volume of substrate-binding pocket was substantially enlarged from 330.5 Å 3 to 409.6 Å 3 . The stability of Lc GluDH was increased ( T m value increased from 47.3 °C to 65.3 °C) by introducing positively charged amino acids or aromatic amino acids at position 375. The desired biocatalytic system was constructed by coupling the engineered Lc GluDH and an NAD + -dependent FDH. Through this biocatalytic system, the batch production of l -PPT exhibited high space-time yield (207.3 g ⋅ L −1 ⋅ day −1 ) with strict stereoselectivity ( ee of l -PPT>99%). Furthermore, eight other chiral amino acids were synthesised by the developed NAD(H)-driven biocatalytic system with high ee values.
研究领域:
生物化学
·
生物技术
·
药物化学
·
酶学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）