TALANTA
·
2021
·
IF 6.057
Yong Chang,Xiaohua Ma,Ting Sun,Lin Liu,Yuanqiang Hao
In the classical heterogeneous electrochemical assay, phosphorylation of peptide substrate is usually performed on the solid-liquid surface. However, immobilization of probe on the solid surface may limit the interaction between the reaction site of probe and the active center of kinase due to the steric hindrance effect. In this work, we proposed a heterogeneous electrochemical method for kinase detection, in which the probe is immobilization-free during the phosphorylation reaction. A biotinylated peptide was used as the kinase substrate. After phosphorylation, the biotinylated phosphopeptide was captured by the neutravidin (NA)-modified electrode through the avidin-biotin interaction. The phosphate groups on the electrode surface were then recognized by the conjugates preformed between biotinylated Phos-tag™ (Bio-tag-Phos) and ferrocene (Fc)-capped NA-modified gold nanoparticle (Fc-AuNP-NA). The method integrates the advantages of homogeneous reaction and heterogeneous detection with high simplicity, sensitivity and specificity. The strategy can be applied to design other heterogeneous biosensors without the immobilization of probe during the enzyme catalyzed reaction .
研究领域:
生物化学
·
分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF POLYMER RESEARCH
·
2024
·Vol. 31
·期 6
·1-13
·
IF 2.6
Wang Wenheng,Liao Mingyi,Wang Lei
The binary segmented styrene-butadiene rubber (SSBR) have been synthesized using butadiene (Bd) and styrene (St) as monomers through living anionic polymerization. This study investigates the loss peak transition mechanism, phase transition mechanism, and the relationship among structure, phase state, and dynamic mechanical properties of segmented SSBR. The results indicate that the two-segment polymerization method allows for precise control of the sequence structure of binary segmented SSBR. The change in the loss peak of SSBR is continuously observed. The phase structure of SSBR can be altered by adjusting the length ratio of the soft and hard segments, which makes structure transition from phase separation to partial compatibility, and ultimately to full compatibility. Furthermore, the mass ratio of Bd/St within the soft and hard segments can be manipulated to influence the compatibility of the SSBR system. TEM images reveal that the transition from complete phase separation to partial compatibility, and ultimately full compatibility, can be represented by changes in the size and distribution of Bd aggregate particles, transitioning from large-sized, mixed-sized particles to uniformly small-sized particles.
研究领域:
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2018
·Vol. 8
·期 68
·38850-38859
·
IF 2.936
Yaozu Guo,Dong Zhao,Junhua You,Wenli Pei,Yingdong Qu,Xiaoyang Wang,Qingyu Meng
Nd2Fe14B nanoparticles were successfully prepared by using a low-energy chemical method. The microscopic characteristics and formation mechanisms of the phases were investigated at each stage during the preparation of Nd-Fe-B nanoparticles. The Nd-Fe-B intermediates, Nd-Fe-B oxides and reduced Nd-Fe-B nanoparticles were detected and analyzed by using TEM, STEM, XRD, SEM, VSM and Rietveld calculations. The results showed that the intermediate of Nd-Fe-B consisted of Fe3O4 and Nd and Fe elements surrounded by nitrile organic compounds. The Nd-Fe-B oxide was composed of NdFeO3 (48.619 wt%), NdBO3 (31.480 wt%) and α-Fe (19.901 wt%), which was formed by the reaction among Nd, Fe3O4 and B2O3. NdFeO3 and NdBO3 exhibited a perovskite-like lamellar structure, and the grain size was smaller than that of α-Fe. Nd-Fe-B particles were mainly composed of Nd2Fe14B and α-Fe phases. The small particles of NdFeO3 and NdBO3 and the interstitial position between oxide particles and α-Fe were more favorable for the formation of Nd2Fe14B particles. At the same time, the surface of α-Fe particles can also diffuse to form Nd2Fe14B nanoparticles. The coercivity of Nd-Fe-B particles was 5.79 kOe and the saturation magnetization was 63.135 emu g−1.
研究领域:
材料科学
·
纳米材料
·
磁性材料
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无机非金属材料
·
固体化学
✓ 已验证
DOI
高影响因子
Biosensors-Basel
·
2021
·Vol. 11
·期 10
·362
·
IF 5.519
Ning Xia,Gang Liu,Xinyao Yi
The heterogeneous assays of proteases usually require the immobilization of peptide substrates on the solid surface for enzymatic hydrolysis reactions. However, immobilization of peptides on the solid surface may cause a steric hindrance to prevent the interaction between the substrate and the active center of protease, thus limiting the enzymatic cleavage of the peptide. In this work, we reported a heterogeneous surface plasmon resonance (SPR) method for protease detection by integration of homogeneous reaction. The sensitivity was enhanced by the signal amplification of streptavidin (SA)-conjugated immunoglobulin G (SA-IgG). Caspase-3 (Cas-3) was determined as the model. A peptide labeled with two biotin tags at the N- and C-terminals (bio-GDEVDGK-bio) was used as the substrate. In the absence of Cas-3, the substrate peptide was captured by neutravidin (NA)-covered SPR chip to facilitate the attachment of SA-IgG by the avidin-biotin interaction. However, once the peptide substrate was digested by Cas-3 in the aqueous phase, the products of bio-GDEVD and GK-bio would compete with the substrate to bond NA on the chip surface, thus limiting the attachment of SA-IgG. The method integrated the advantages of both heterogeneous and homogeneous assays and has been used to determine Cas-3 inhibitor and evaluate cell apoptosis with satisfactory results.Keywords:surface plasmon resonance;protease;caspase;avidin-biotin interaction
研究领域:
生物化学
·
分子生物学
·
分析化学
✓ 已验证
DOI
PubMed
高影响因子
TALANTA
·
2021
·
IF 6.057
Ning Xia,Ting Sun,Lin Liu,Linxu Tian,Zhifang Sun
Heterogeneous analysis has great application prospects in the detection of post-translational modification (PTM) enzymes with the advantages of signal enhancement, less sample demand, and high sensitivity and selectivity . Nevertheless, once the substrate was fixed on a solid interface, the steric hindrance might limit the approaching of catalytic center to the substrate, thus reducing the efficiency of PTM. Herein, we suggested that the avidin-modified interface could be used to develop heterogeneous sensing platforms with biotin-labeled substrates as the probes, in which the enzymatic PTM was performed in solution and the heterogeneous assay was conducted on a solid surface. The sensing strategy integrates the advantages but overcomes the defects of both homogeneous and heterogeneous assays. Protein kinase A (PKA) and histone acetyltransferase (HAT) were determined as the examples by using sequence-specific peptide substrates. The signal changes were monitored by HRP-based colorimetric assay and antibody-amplified surface plasmon resonance (SPR). The methods were used for analysis of cell lysates and evaluation of inhibition efficiency with satisfactory results. The strategy can be used for the detection of a variety of biological enzymes and provide a new idea for the design of various heterogeneous biosensors. Thus, this work should be of great significance to the popularization and practical application of biosensors.
研究领域:
生物化学
·
分子生物学
·
分析化学
·
生物技术
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2021
·
IF 8.128
Wellars Utetiwabo,Lei Zhou,Muhammad Khurram Tufail,Xintao Zuo,Le Yang,Jinfeng Zeng,Ruiwen Shao,Wen Yang
Defect engineering through induction of dislocations is an efficient strategy to design and develop an electrode material with enhanced electrochemical performance in energy storage technology. Yet, synthesis, comprehension, identification, and effect of dislocation in electrode materials for lithium-ion batteries (LIBs) are still elusive. Herein, we propose an ethanol-thermal method mediated with surfactant-template and subsequent annealing under air atmosphere to induce dislocation into titanium niobium oxide (Ti 2 Nb 14 O 39 ), resultant nanoscale-dislocated-Ti 2 Nb 14 O 39 (Nano- dl -TNO). High-resolution transmission electron microscope (HRTEM), fast Fourier transform (FFT), and Geometrical phase analysis (GPA) denote that the high dislocation density engraved with stacking faults forms into the Ti 2 Nb 14 O 39 lattice. The presence of dislocation could offer an additional active site for lithium-ion storage and tune the electrical and ionic properties of the Ti 2 Nb 14 O 39 . The resultant Nano- dl -TNO delivers superior rate capability, high specific capacity, better cycling stability, and making Ti 2 Nb 14 O 39 a suitable candidate among fast-charging anode materials for lithium-ion batteries. Moreover, In-situ High-resolution transmission electron microscope (HRTEM) and Geometrical phase analysis (GPA) evinces that the removal of the dislocated area in the Nano- dl -TNO leads to the contraction of the lattice, alleviation of the total volume expansion, causing the symmetrization and preserves structural stability. The present findings and designed approach reveal the rose-colored perspective of dislocation engineering into mixed transition metal oxides as next-generation anodes for advanced lithium-ion batteries and all-solid-state lithium-ion batteries.
研究领域:
材料科学
·
储能技术
·
纳米技术
·
电化学
·
电池技术
✓ 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）