CATALYSIS COMMUNICATIONS
·
2018
·
IF 3.463
Marzieh Ghadamyari,Somboon Chaemchuen,Kui Zhou,Michiel Dusselier,Bert F. Sels,Bibimaryam Mousavi,Francis Verpoort
Poly (lactic acid) (PLA) is extensively used as an eco-friendly compound for many applications. The synthesis of stereo-pure lactide, specifically l , l -lactide which is the most desired isomer for the synthesis of high-quality PLA is very important. In this work, various materials including MOFs and simple bases have been applied as catalysts for the Lactide synthesis. Herein we report the one-step synthesis of l , l -lactide with high selectivity and yield (99%) in the absence of racemization by applying a cost-effective Cs 2 CO 3 catalyst. The novel described procedure is even expected to be very efficient for industrial applications.
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高影响因子
Environmental Science and Ecotechnology
·
2024
·
IF 14
Chang Liu,Lin Li,Linji Xu,Tanglong Zhang,Qiang He,Xiaodong Xin
N,N bis(carboxymethyl)- l -glutamate (GLDA) is an eco-friendly chelating agent that effectively extracts multivalent metal ions from waste activated sludge (WAS) flocs, which could potentially alter their structure. However, the effect of GLDA on the production of volatile fatty acids (VFAs) from WAS is not well known. Here, we demonstrate that pretreatment with GLDA at a concentration of 200 mmol per kg VSS results in a significant increase of 142 % in extractable extracellular polymeric substances and enhances the total VFAs yield by 64 % compared to untreated samples. We reveal GLDA's capability to mobilize organic-binding multivalent metal ions within sludge flocs. Specifically, post-pretreatment analyses showed the release of 69.1 mg L −1 of Ca and 109.8 mg L −1 of Fe ions from the flocs, leading to a more relaxed floc structure and a reduced apparent activation energy (10.6 versus 20 kJ mol −1 ) for WAS solubilization. Molecular dynamic simulations further demonstrate GLDA's preferential binding to Fe 3+ and Ca 2+ over Mg 2+ . Our study suggests that GLDA pretreatment causes minimal disruption to reactor stability, thereby indicating the stability of microbial community composition. GLDA has emerged as a viable pretreatment agent for enhancing volatile fatty acids production from waste activated sludge.
研究领域:
环境工程
·
废水处理
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生物技术
·
化学工程
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PubMed
高影响因子
Journal of Macromolecular Science Part B-Physics
·
2020
·
IF 0.911
Hailin Xie,Zhihua Zhou,Wenjuan Liu,Yanmin Zhao,Tianlong Huang,Ping Chen,Ziwei Zhou,Dan Wang,Jianglong Duan,Jianjun Fang
Polymeric/ceramic composite scaffolds that are biocompatible and biodegradable are widely used for tissue engineering applications. In this work a series of poly(L-lactide-co-glycolide-co-ε-caprolactone)/nano-biaoactive glass-nano-β-tricalcium phosphate composite scaffolds were successfully fabricated and the influences of the inorganic content and freezing temperature on the physical properties were studied. The composite scaffolds with various inorganic contents showed an interconnected pore structure with irregular shapes. The composite scaffolds had a porosity that was reduced with increasing inorganic content and decreasing freezing temperature. The incorporation of inorganic fillers and decreasing freezing temperature improved the mechanical properties of the hybrid scaffolds. By appropriate control of these two factors (10.0 wt% content of NBAG and β-TCP with freezing at −30 °C) a suitable composite scaffold was prepared as a potential bone tissue engineering implant.
研究领域:
生物材料
·
组织工程
·
高分子科学
·
陶瓷材料
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材料科学
·
纳米技术
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高影响因子
Analytical Methods
·
2016
·Vol. 8
·期 17
·3481-3487
·
IF 1.915
Lili Wang,Wencheng Gong,Fang Wang,Zhenya Yu,Zilin Chen
An efficient bienzyme nanocomposite film-based biosensor for L-amino acid recognition has been developed and characterized. The biosensor was fabricated by immobilizing horseradish peroxidase (HRP) and L-amino acid oxidase (L-AAODx) in poly(toluidine blue) film (polyTB) at the surface of a multi-walled carbon nanotube (CNTs) modified glassy carbon electrode (GCE). Only L-amino acids can be electrochemically oxidized by L-AAODx in the presence of oxygen (O2) to produce hydrogen peroxide (H2O2), which can be further reduced to H2O by HRP at a low potential of −0.1 V. The concentration of L-amino acids was estimated by the reduction current of H2O2. The polyTB film, acting as the enzyme-immobilization carrier and redox mediator, accelerated electron transfer between analytes and the electrode. At the same time, CNTs with excellent conductivity and strong adsorption ability enhanced the utilization of the enzymes. The performance of this biosensor was evaluated by electrochemical techniques and it showed high selectivity and fast response for the chiral recognition of L-amino acids, including L-tryptophan (L-Trp), L-phenylalanine (L-Phe) and L-tyrosine (L-Tyr). The low potential reduced the interference of some coexisting biomolecules for the determination of the L-amino acids. The recovery of the three amino acids in milk indicated the feasibility of this biosensor for use in complex samples.
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高影响因子
JOURNAL OF FLUORESCENCE
·
2025
·
IF 3.1
Chen Xin,Wang Qing-wan,Zhan Tong-ling,Sun Yue,Zhang Xiao-rui,Liu Kun,Liu Xiao-wu
Nitrogen@Carbon quantum dots (N@CQDs) are prepared using microwave hydrothermal method, and polyvinylpyrrolidone (PVP) and melamine are used as mixed C source and N source. Microwave reaction conditions of preparing the N@CQDs are 170 ℃ and 3 h. This N@CQDs are are used as fluorescence probe for detection of amino acids. The N@CQDs can recognize L-alanine in water solution, and simultaneously recognize both L-methionine and L-cysteine in dimethyl sulfoxide (DMSO) solution. The linear ranges for L-alanine, L-methionine and L-cysteine are 0–15 µM, 2–50 µM and 0–17 µM, respectively. While limits of detection (LOD) for them are 11.092 nM, 7.8067 nM and 0.67476 nM, respectively. Compared to presently available detection methods, as-prepared N@CQDs have the advantage of high sensitivity and selectivity. Furthermore, coexistence of other amino acids has minimal interference in the detection of L-alanine, L-methionine and L-cysteine. For the as-prepared N@CQDs, solvent plays important roles in influencing the identification of amino acid types and detection sensitivity.
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PubMed
高影响因子
MICROCHIMICA ACTA
·
2020
·Vol. 187
·期 12
·1-11
·
IF 6.232
Chu Xu,Ning Gan,Zhou Zhiqiang,Liu Yi,Xiao Qi,Huang Shan
A one-pot hydrothermal synthesis of manganese-doped carbon dots (Mn-CDs) is reported for fluorescent “on-off-on” determination of Mn(VII) and L-ascorbic acid (L-AA) in aqueous solution and living cells. Mn-CDs were prepared by using sulfanilic acid, tetrakis(hydroxymethyl)phosphonium chloride, and Mn(II) chloride as precursors. Mn-CDs were characterized by several spectroscopic methods and microscopic techniques. Mn-CDs show distinctly long fluorescence lifetime (12.39 ± 0.07 ns) and high absolute fluorescence quantum yield (around 37%) with excitation and emission wavelengths of 362 and 500 nm, respectively. Mn-CDs exhibit no significant cytotoxicity to human cervical carcinoma HeLa cells and human embryonic kidney HEK-293T cells at 200 μg mL −1 level after 48 h incubation. The fluorescence of Mn-CDs at 500 nm (excited at 362 nm) is quenched efficiently by Mn(VII) and can be further recovered after the addition of L-AA, resulting in a fluorescent “on-off-on” assay for the determination of Mn(VII) and L-AA. Under optimal experimental conditions, the linear response covers the 3 to 150 μM Mn(VII) concentration range and the 3 to 140 μM L-AA concentration range. This method offers relatively low detection limits of 0.66 μM for Mn(VII) and 0.90 μM for L-AA. This strategy was applied to visual determination of Mn(VII) and L-AA in living HeLa cells with satisfying results.
Schematic presentation of bright Mn-CD-based fluorescence “on-off-on” assay for both Mn(VII) and L-AA. This fluorescent assay possessed low detection limit of 0.66 μM for Mn(VII) and 0.90 μM for L-AA. This strategy was applied for visual determination of Mn(VII) and L-AA in living HeLa cells with satisfying results.
研究领域:
分析化学
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材料科学
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生物化学
·
细胞生物学
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PubMed
高影响因子
Small
·
2024
·
IF 13
Lihua Chen,Hui Ming,Bowen Li,Chen Yang,Shanshan Liu,Yajie Gao,Tingting Zhang,Canhua Huang,Tingyuan Lang,Zhuo Yang
Cancer metastasis poses significant challenges in current clinical therapy. Osthole (OST) has demonstrated efficacy in treating cervical cancer and inhibiting metastasis. Despite these positive results, its limited solubility, poor oral absorption, low bioavailability, and photosensitivity hinder its clinical application. To address this limitation, a glutathione (GSH)-responded nano-herb delivery system (HA/MOS@OST&L-Arg nanoparticles, HMOA NPs) is devised for the targeted delivery of OST with cascade-activatable nitric oxide (NO) release. The HMOA NPs system is engineered utilizing enhanced permeability and retention (EPR) effects and active targeting mediated by hyaluronic acid (HA) binding to glycoprotein CD44. The cargoes, including OST and L-Arginine (L-Arg), are released rapidly due to the degradation of GSH-responsive mesoporous organic silica (MOS). Then abundant reactive oxygen species (ROS) are produced from OST in the presence of high concentrations of NAD(P)H quinone oxidoreductase 1 (NQO1), resulting in the generation of NO and subsequently highly toxic peroxynitrite (ONOO − ) by catalyzing guanidine groups of L-Arg. These ROS, NO, and ONOO − molecules have a direct impact on mitochondrial function by reducing mitochondrial membrane potential and inhibiting adenosine triphosphate (ATP) production, thereby promoting increased apoptosis and inhibiting metastasis. Overall, the results indicated that HMOA NPs has great potential as a promising alternative for the clinical treatment of cervical cancer.
研究领域:
药学
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纳米技术
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癌症研究
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药物递送系统
·
生物化学
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DOI
PubMed
高影响因子
JOURNAL OF POLYMER SCIENCE
·
2021
·Vol. 59
·期 24
·3111-3121
·
IF 0
Xu Zhang,Wei Zhao,Chengliang Wang,Lan Cao,Qingfu Wang,Jingjiang Sun
In this work, a series of polyesters with different functional side groups were successfully prepared by Passerini three-component polymerization (P-3CP) in “one-pot” from biorenewable l -glutamic acid ( l -GA)-based monomers. First, the polymerization conditions including monomer feed ratios, solvents and comonomer were systematically studied using Boc-protected l -GA with adipaldehyde and tert -butyl isocyanide. Under the optimal polymerization conditions, a variety of N -substituted l -GA-based monomers as well as functional isocyanides were attempted in the P-3CP to produce polyesters with different functionalities. Moreover, it was found that after removal of pendant protecting groups, the obtained l -GA-based polyester degraded spontaneously into small molecules via 1,5-intramolecular cyclization between the pendant amine groups and the ester groups in polymer backbone. The structures and thermal properties of obtained polymers were determined by 1 H NMR, IR, SEC, MALDI-ToF-MS, DSC, and TGA measurements. Starting from biorenewable l -GA, this approach will provide a facile and straightforward route to produce functional and biodegradable polyesters, thus effectively expanding the range of biodegradable polymers. Graphical
研究领域:
材料科学
·
高分子化学
·
生物降解高分子
·
可持续化学
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DOI
JOURNAL OF CHEMICAL THERMODYNAMICS
·
2016
·
IF 2.196
Hujun Xie,Lijiang Zhao,Chengcheng Liu,Yifan Cao,Xiaoxing Lu,Qunfang Lei,Wenjun Fang
The densities of aqueous solutions of glycine, l -serine, l -alanine, l -proline with the ionic liquid (IL), 1-phenylpiperazinium tetrafluoroborate ([Phpi][BF 4 ]) at the IL concentrations of (0.025, 0.055 and 0.100) mol·kg −1 have been measured at the temperatures of (298.15, 303.15 and 308.15) K. On the basis of the experimental results, the apparent molar volume ( V Ф ), standard partial molar volume ( V Ф 0 ), transfer partial molar volume (Δ tr V Φ 0 ) and hydration number ( n H ) have been calculated. The hydrophilic–hydrophilic, hydrophobic–hydrophilic and hydrophobic–hydrophobic interactions are involved in the studied systems of {[Phpi][BF 4 ] + amino acids + H 2 O. These volumetric parameters can help to understand the mixing effects and other complex biological processes between amino acids and ionic liquid aqueous solution.
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高影响因子
APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY
·
2020
·Vol. 192
·期 3
·935-951
·
IF 2.277
Guo Zongren,Long Liangkun,Ding Shaojun
L-Ribulose and L-ribose are two high-value unnatural sugars that can be biosynthesized by sugar isomerases. In this paper, an L-arabinose isomerase (BvAI) from Bacillus velezensis CICC 24777 was cloned and overexpressed in Escherichia coli BL21 (DE3) strain. The maximum activity of recombinant BvAI was observed at 45 °C and pH 8.0, in the presence of 1.0 mM Mn 2+ . Approximately 207.2 g/L L-ribulose was obtained from 300 g/L L-arabinose in 1.5 h by E. coli harboring BvAI. In addition, approximately 74.25 g/L L-ribose was produced from 300 g/L L-arabinose in 7 h by E. coli co-expressing BvAI and L-RI from Actinotalea fermentans ATCC 43279 (AfRI). This study provides a feasible approach for producing L-ribose from L-arabinose using a co-expression system harboring L-Al and L-RI.
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PubMed
高影响因子
Gels
·
2024
·Vol. 10
·期 12
·808
·
IF 5
Feng Li,Ruoxi Yang,Jian Xu,Guohai Xu,Ye Wu
The concentration of small molecules reflects the normality of physiological processes in the human body, making the development of simple and efficient detection equipment essential. In this work, inspired by a facile strategy in point-of-care detection, two devices were fabricated to detect small molecules via photocurrent measurement. A linear response of the photocurrent against the concentration of the small molecules was found. In the first device, metal ions were introduced into gel substrates made by xanthan gum to enhance photocurrent response. N-phenyl-2-naphthylamine was measured when iron or manganese ions were used. L-Phenylalanine was measured when the gel was modified by samarium, iron, cerium, or ytterbium ions. L-(+)-Arabinose was detected via the gels modified by iron or holmium ions. D-(+)-Mannose was detected when the gel was modified by ytterbium, manganese, chromium, or sodium ions. L-Methionine was detected in the gels modified by samarium, zinc, or chromium ions. The second device was based on a paper sheet. A sugar-like molecule was first synthesized, which was then used to modify the paper. The detection was possible since the photocurrent showed a linear trend against the concentration of D-Trehalose. A linear fit was conducted to derive the sensitivity, whose value was found to be 5542.4. This work offers a novel, simple, and environmentally sustainable platform that is potentially useful in remote areas lacking medical devices.
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PubMed
高影响因子
Scientific Reports
·
2024
·Vol. 14
·期 1
·1-13
·
IF 3.8
Liao Yiqi,Wang Yanfang,Huang Weirui,Wang Junxiang,Guo Mu,Zhang Jiahui,Zheng Hanlu,Yan Yingxue,Lin Zhaolong,Qiu Nengfu,Yu Xiangbin,Yu Yue
Slow Transit Constipation (STC) is characterized by impaired colonic motility, but its relationship with gut microbiota remains unclear. This study investigated the correlation between specific gut microbial populations and STC, focusing on the Lactobacillus acidophilus to Lactobacillus johnsonii (A/J) ratio. We used four rat groups: Control (CON), Loperamide-induced STC (LOP), antibiotic-treated (ABX), and antibiotic plus Loperamide (ABX + LOP). Fecal samples were analyzed using 16S rRNA gene sequencing, and serum metabolites were examined through LC–MS. The LOP group showed an increased A/J ratio, while ABX and ABX + LOP groups had decreased ratios. Notably, the ABX + LOP group did not develop STC symptoms. Metabolomic analysis revealed alterations in key metabolites across groups, including changes in levels of guanidinoacetate, glycine, l -glutamine, nicotine, and nicotinate d -ribonucleotide in the LOP group, and variations in l -glutamine, l -phenylalanine, l -tyrosine, histamine, d -ornithine, and lecithin in the ABX and ABX + LOP groups. Our findings suggest a correlation between the A/J ratio and STC development, offering insights into STC pathophysiology and potential microbiome-targeted therapies.
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高影响因子
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