ANALYST
·
2022
·Vol. 147
·期 8
·1631-1640
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IF 5.227
Yunkang Ma,Chenhui Wu,Wenjie Yang,Zhigang Gao,Lihua Chen
Mycoplasma ovipneumoniae (MO), a disease-causing pathogen with some of the highest levels of morbidity and mortality, can spread silently at the herd level. A novel alternative nanoprobe for MO was prepared using porous metal–organic frameworks (MOFs) as the scaffold and hairpin DNA with specific sequences of MO and G4 segments as the probe. This preparation was based on the strong fluorescence emission by ThT (thioflavin T) in the limitation of G-quadruplexes with a cavity structure. The use of MOFs effectively limited the folding behavior of G4 as a part of the probe to improve the defect of the strong background signal caused by the free-state G4Probe in a buffer. The results from the selectivity experiment showed that only a trace amount of the target with lower ΔG could be the “key” to the highly efficient triggering of the release behavior of the G4Probe from MOFs and the subsequent change in the fluorescence behavior of ThT. The DNA targets could be determined by observing the change in the signal. More importantly, the probe showed a low detection limit and a good linear correlation between the concentration of target DNA ranging from 10−10 M to 10−6 M not only in buffer but also in natural complex media. Moreover, the operation involved in the whole strategy was simple and the total cost was low. These findings demonstrated the value of the probe in further clinical diagnosis. This study reports the successful construction of a ΔG-sensitive sensor for MO for the first time.
研究领域:
生物技术
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微生物学
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分析化学
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纳米技术
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DOI
PubMed
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2023
·
IF 9.9
Xiaodong Hao,Xishuo Zhang,Yang Xu,Yuhao Zhou,Tingting Wei,Zhuangzhuang Hu,Lei Wu,Xinyi Feng,Jin Zhang,Yi Liu,Deqiang Yin,Shufang Ma,Bingshe Xu
To understand the underlying mechanism of the interfacial charge transfer and local chemical state variation in the nonprecious-based hydrogen evolution reaction (HER) electrocatalysts, a model system of the NiO/CeO 2 heterostructure was chosen for investigation using a combination of the advanced electron microscopic characterization and first-principles calculations. The results directly proved that interfacial charge transfer occurs from Ni to Ce, leading to reduction in the valence state of Ce and increased formation of V O . This would optimize ΔG H* and facilitate the hydrogen evolution process, resulting in outstanding HER performance in 1 M KOH with a low overpotential of 99 mV at the current density of 10 mA•cm −2 and a modest Tafel slope of 78.4 mV•dec −1 for the NiO/CeO 2 heterostructure sample. Therefore, the improved HER performance could be attributed to the synergistic coupling interactions and electron redistribution at the interface of NiO and CeO 2 . These results concretely demonstrate the direct determination of the interfacial structure of the heterostructure and provide atomistic insights to unravel the underlying mechanism of interfacial charge transfer induced HER performance improvement.
研究领域:
材料科学
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电化学
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催化
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表面科学
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产品关联
DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
·
IF 8.1
Almire Dolkun,Turghun Muhammad,Junxia Gao,Yuanyuan Chen,Yan Zhang,Defu Zhi,Shubiao Zhang
Accurate and real-time measurement of flavonoid concentration during the adsorption process is vital for understanding its adsorption mechanism. In this study, a new merging-zone flow injection analysis (FIA) method based on the NaNO 2 -AlCl 3 -NaOH colorimetric reaction was developed for automatic determination of flavonoid concentration in plant extracts and in adsorption solution during batch adsorption process. The method parameters were optimized using a univariate experimental design, and rutin standard solutions in the concentration range of 25–800 mg/L showed good linearity (R 2 = 0.9994) with the FIA signal. The sample throughput was 40 h -1 and the limit of detection was 4.888 mg/L. The adsorption kinetics, isotherms, and thermodynamics of flavonoids from Dracocephalum Moldavia onto HPD 300 resin were investigated at varying initial concentrations and temperatures. The pseudo-first-order kinetic model was found to be suitable at 25 and 35 ℃, while the pseudo-second-order model exhibited superior performance at 45 ℃. The Freundlich model was found to be appropriate for describing the adsorption isotherm. The thermodynamic parameters ΔG and ΔH were both negative, and ΔS was positive, indicating that the adsorption process of flavonoids onto the HPD 300 resin is spontaneous and exothermic. The FIA method can effectively decrease the errors arising from the big adsorption volume change in conventional method during the batch adsorption. The developed method enables rapid and online determination of total flavonoids, reducing both time and labor costs, suitable for routine measurements as well as online monitoring of adsorption processes.
研究领域:
分析化学
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药学
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植物化学
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环境科学
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产品关联
DOI
高影响因子
POLYMER
·
2019
·
IF 3.771
Chao Lv,Ruiyang Wang,Jia Gao,Ning Ding,Shunni Dong,Jingjing Nie,Junting Xu,Binyang Du
Enhanced phase separation and inverse order-to-order phase transition with increasing temperature was observed for a series of poly (acrylic acid)- b -poly (propylene oxide)- b -poly (acrylic acid) triblock copolymers with various block lengths by temperature-variable synchrotron small-angle X-ray scattering (SAXS). This abnormal phase behavior was attributed to the change of hydrogen (H)-bonding interaction in block copolymers upon increasing temperature and theoretically explained from thermodynamic viewpoint. The temperature-dependent FTIR analysis revealed that increasing temperature led to the weakening of overall H-bonding interactions and the increase of free C O and C–O–C groups. The Flory-Huggins interaction parameter χ of PAA and PPO blocks was positive and increased with increasing temperature as determined from the SAXS profiles of disordered block copolymer. The thermodynamic calculation indicated that the increase of Δ H was larger than the decrease of – T Δ S with increasing temperature because of the relatively large value of χ , leading to the increase of overall Δ G mix and hence the enhanced phase separation at higher temperature.
研究领域:
高分子科学
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材料科学
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热力学
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物理化学
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DOI
高影响因子
ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY
·
2016
·
IF 3.13
Qiang Liu,Qinze Liu,Zining Ruan,Xiaoqing Chang,Jinshui Yao
A novel poly(catechol-diethylenetriamine-pphenylenediamine)(PCEA) adsorbent was synthesized in methanol, with chelating groups supplied by catechol and diethylenetriamine, which showed a strong removal performance and efficient adsorption toward Cu(II) ions in aqueous solution. The adsorbent was characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA). Besides, factors such as adsorbent dosage, pH, initial ionic and metal concentrations, contact time, and temperature on the adsorption of Cu(II) were studied. The data revealed that the adsorption followed a pseudo-second order kinetic model and the adsorption rate was influenced by the intra-particle diffusion. Furthermore, the adsorption process followed the Langmuir isotherm model, and the maximum adsorption capacity ( Q m ) was 44.2 mg/g at 298 K in simulated wastewater. The value of Δ G (kJ/mol) and Δ H (kJ/mol) also demonstrated that the adsorption process was spontaneous and endothermic. Studies revealed that PCEA particles were powerful and stable for the removal of Cu(II) in water, and it could be directly applied to the Cu(II)-contaminated water.
研究领域:
环境科学
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材料科学
·
化学工程
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产品关联
DOI
PubMed
高影响因子
Polymers
·
2024
·Vol. 16
·期 10
·1365
·
IF 4.7
Dongxing Li,Hui Jiang,Zhengwei Luo,Wenhua Geng,Jianliang Zhu
This research focuses on modifying discarded feathers by grafting glycidyl methacrylate (GMA) onto their surface through thiolation, followed by an epoxy ring-opening reaction with N-methyl-D-glucamine (NMDG) to synthesize feather-based boron adsorbents. Optimization of the adsorbent preparation conditions was achieved through single-factor experiments, varying temperature, time, GMA concentration, and initiator dosage. The synthesized adsorbent (F-g-GMA-NMDG) underwent characterization using Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and X-ray diffraction (XRD). The adsorption behavior of the adsorbent was studied, and its boron adsorption capacity at different temperatures was determined through static adsorption kinetic curves. Analysis of adsorption isotherms, kinetics, and thermodynamics was conducted. Results indicate that the boron adsorption process by F-g-GMA-NMDG follows a pseudo-second-order model. The adsorption process is endothermic, with higher temperatures promoting adsorption efficiency. Gibbs free energy (ΔG) confirms the spontaneity of the adsorption process. Enhanced adsorption efficacy was observed under neutral and acidic pH conditions. After four cycles, the adsorbent maintained its adsorption efficiency, demonstrating its stability and potential for reuse. This study provides novel insights into both the treatment of discarded feathers and the development of boron adsorbents.
研究领域:
环境科学
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材料科学
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化学工程
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废物管理
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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）