BIOSENSORS & BIOELECTRONICS
·
2015
·
IF 6.409
Cui Ye,Min-Qiang Wang,Xia Zhong,Shihong Chen,Yaqin Chai,Ruo Yuan
One-dimensional Pd–Au nanowires (Pd–Au NWs) were prepared and applied to fabricate an electrochemiluminescence (ECL) biosensor for the detection of acetylcholinesterase (AChE) activity. Compared with single-component of Pd or Au, the bimetallic nanocomposite of Pd–Au NWs offers a larger surface area for the immobilization of enzyme, and displays superior electrocatalytic activity and efficient electron transport capacity. In the presence of AChE and choline oxidase (ChOx), acetylcholine (ATCl) is hydrolyzed by AChE to generate thiocholine, then thiocholine is catalyzed by ChOx to produce H 2 O 2 in situ , which serves as the coreactant to effectively enhance the ECL intensity in luminol-ECL system. The detection principle is based on the inhibited AChE and reactivated AChE as dual biomarkers, in which AChE was inhibited by organophosphorus (OP) agents, and then reactivated by obidoxime. Such dual biomarkers method can achieve credible evaluation for AChE activity via providing AChE activity before and after reactivation. The liner range for AChE activity detection was from 0.025 U L −1 to 25 KU L −1 with a low detection limit down to 0.0083 U L −1 .
研究领域:
分析化学
·
生物传感器
·
纳米材料
·
酶活性检测
✓ 已验证
DOI
高影响因子
JOURNAL OF NUCLEAR MATERIALS
·
2026
·
IF 3.3
Fenglei Wang,Chaofan Jiang,Wenting Liu,Yuchen Jiang,Huimin Li,Yuanhua Wang,Yongdong Jin,Chuanqin Xia,Lijian Ma
Amorphous zeolite imidazolate framework-8 shows excellent leaching resistance for Eu3+, Th4+, and UO22+ in acidic conditions. • Compressed pores and ion hydrolysis work together to immobilize radionuclides. • A low‑energy, environmentally friendly way that could effectively immobilize Eu3+, Th4+, and UO22+ at room temperature. The proper treatment of high-level liquid waste (HLW) was critical for the sustainability of the nuclear industry. Conventional immobilization methods (glass, cement, and ceramic) had limitations such as high energy consumption, volatile radionuclide release, or waste volume increase. Here, we reported a new strategy to immobilize key radionuclides using zeolitic imidazolate framework-8 (ZIF-8) under high pressure at room temperature, addressing limitations of conventional immobilization. ZIF-8 could be loaded with 10 wt% representative radionuclides (Cs + , Sr 2+ , Eu 3+ , Th 4+ , UO 2 2+ ) and ReO 4 - (a 99 TcO 4 - surrogate), then was amorphized under 1.2 GPa to form glassy ZIF-8 (ZIF-8-G). Finally, after leaching by deionized water or pH = 2 HNO 3 for 42 days, in both leaching solutions, Eu 3+ , Th 4+ , and UO 2 2+ were undetectable, due to their strong interactions with the N-Zn bonds in ZIF-8-G and their hydrolysis into insoluble hydroxides during the heating and loading process, which were then immobilized within ZIF-8-G under high pressure; ≈12% ReO 4 - was leached out because of the larger ionic diameter of ReO 4 - (3∼4 Å)than the pore size of ZIF-8-G (< 3.6 Å); While Cs + and Sr 2+ were completely leached out due to the smaller ionic diameter of Cs + and Sr 2+ (< 3 Å). Compared with conventional immobilization techniques, this technology offers advantages including low-cost raw materials, scalability for large-scale industrial production, simple processing, and environmental friendliness. Download: Download high-res image (281KB) Download: Download full-size image
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2023
·
IF 9.5
Ying Zhang,Bin Wei,Hao Liang
An organometallic complex-catalyzed artificial coenzyme regeneration system has attracted widespread attention. However, the combined use of organometallic complex catalysts and natural enzymes easily results in mutual inactivation. Herein, we establish a rhodium-based metal–organic framework (MOF)-on-MOF difunctional core–shell nanoreactor as an artificial enzymatic NAD(P)H regeneration system. UiO67 as the core is used to capture rhodium molecules for catalyzing NAD(P)H regeneration. UiO66 as the shell is used to specifically immobilize His-tagged lactate dehydrogenase (LDH) and serve as a protection shield for LDH and [Cp*Rh(bpy)Cl]+ to prevent mutual inactivation. A variety of results indicate that UiO67@Rh@UiO66 has good activity in realizing NAD(P)H regeneration. Noteworthily, UiO67@Rh@UiO66@LDH maintains a high activity level even after 10 cycles. This work reports a novel NAD(P)H regeneration platform to open up a new avenue for constructing chemoenzyme coupling systems.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
·
2023
·Vol. 24
·期 4
·3864
·
IF 5.6
Kangjing Wang,Liting Zhao,Ting Li,Qian Wang,Zhongyang Ding,Weifu Dong
Ion exchange resins are suitable as carriers for immobilized enzymes because of their stable physicochemical properties, appropriate particle size and pore structure, and lower loss in continuous operation. In this paper, we report the application of the Ni-chelated ion exchange resin in the immobilization of His-tagged enzyme and protein purification. Acrylic weak acid cation exchange resin (D113H) was selected from four cationic macroporous resins that could chelate the transition metal ion Ni. The maximum adsorption capacity of Ni was ~198 mg/g. Phosphomannose isomerase (PMI) can be successfully immobilized on Ni-chelated D113H from crude enzyme solution through chelation of transition metal ions with the His-tag on the enzyme. The maximum amount of immobilized PMI on the resin was ~143 mg/g. Notably, the immobilized enzyme showed excellent reusability and maintained 92% of its initial activity with 10 cycles of catalytic reaction. In addition, PMI was successfully purified using an affinity chromatography column prepared by Ni-chelated D113H, which showed the potential for the immobilization and purification process to be realized in one step.Keywords:ion exchange resin;His-tag;immobilization;enzyme activity;protein purification;reusability
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
·
2023
·
IF 6
Xuelian Yan,Peiling Yuan,Xiang Meng,Rui Hu
With the assistance of preinstalled silica templates, polymeric graphitic carbon nitride with enhanced porosity suffers from complicated procedures and by-product wastes. Besides, it is still difficult to achieve the incorporation of phosphate groups with high contents on carbon-based materials (mostly < 1.0 at.% of P) via a one-step preparation since phosphate species on the surfaces of sorbents could complex heavy metals strongly from wastewaters. Given the porosity engineering of guanidine phosphate (GP) for carbonaceous materials, GP activated graphitic carbon nitrides (GPCNs) with developed surface area (4.2–4.8 fold of enhancement than inactivated one) and abundant phosphate groups (9.9–16.7 at.% of P) were fabricated via a one-step pyrolysis at 450, 500, and 550 °C. On this basis, the sorption of Pb(II) on GPCNs were studied under geochemical conditions including contact time, solution pH, ionic strength, humic acid concentration, interfering cations and anions, and temperature. GPCN pyrolyzed at 500 °C could capture Pb(II) rapidly (20.0 min) with superior maximum capacities (81.8–217.1 mg/g at pH 5.0, T 298 K), excellent selectivity coefficients (8.10–16.54) and favorable reusability (81.4% of capacity remained). The formation of minerals was dominant for the selectivity rather than ion exchange or surface coordination, etc. This work starts up the facile activation of carbon nitride with developed porosity and surface functionality to manage aquatic pollutants.
✓ 已验证
产品关联
DOI
高影响因子
Microbial Cell Factories
·
2022
·Vol. 21
·期 1
·1-13
·
IF 6.352
Zhong Zhi-Hao,Zhang Yu-Qing
Background The immobilized technology for microbial or cells has the advantages of high microbial activity, high microbial density per unit space, good tolerance, strong shock, load resistance, high processing efficiency, and high reuse rate. It is now widely used in environmental remediation, water quality treatment, biodegradation, food industry, chemical analysis, energy development, medicine and pharmaceuticals, and other fields.Results A novel Escherichia coli cell-immobilizing polyvinyl alcohol hydrogel membrane (ECI-PVAHM) was prepared by unidirectional nanopore dehydration (UND) from a 10% polyvinyl alcohol (PVA) aqueous solution containing enhanced green fluorescent protein-labeled E. coli. This bacteria-loaded film has high water stability, flexibility, transparency, and mechanical robustness. Its tensile strength, elongation rate, and swelling rate are in the ranges 0.66–0.90 MPa, 300–390%, and 330–800%, respectively. The effective bacterial load of ECI-PVAHM is 2.375 × 109–1010 CFU/g (dry weight), which does not affect the original crystal structure of the PVAHM. This biofilm has a porous network structure with pore sizes between 0.2 and 1.0 μm, and these cells are embedded in the PVAHM network. When the immobilized cells were continuously cultured for 20 days, and the medium was renewed twice daily, their relative proliferation efficiency after 40 cycles could still be maintained at ~ 91%.Conclusion The above results show that the cell division, proliferation ability, and metabolic activity of immobilized E. coli were not affected by the physical barrier of the porous network structure of the hydrogel. This UND-based ECI-PVAHM has potential applications in molecular biology, biopharmaceutical expression and production, bioreactors, and fuel cells.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY
·
2022
·Vol. 195
·期 2
·1216-1230
·
IF 3.094
Cheng Qiaojuan,Chi Xinyu,Liang Yingchao,Li Wanxin,Sun Jiaxin,Tao Jin,Wang Zhi
Metal–organic frameworks (MOFs) can be used as the immobilization carriers to protect the physicochemical properties of enzymes and improve their catalytic performance. Herein, we report an in situ co-precipitation method to immobilize lipase from Candida sp. 99–125 in Cu-BTC MOF (BTC = 1, 3, 5-benzene tricarboxylic acid, H 3 BTC). Characterizations of the immobilized lipase (lipase@Cu-BTC) have confirmed the entrapment of lipase molecules in Cu-BTC MOF. The immobilized lipase has been successfully applied for resolving N- hydroxymethyl vince lactam ( N -HMVL) and its catalytic activity is five times that of native enzyme. More importantly, we found that Cu-BTC MOF can afford powerful protection for enzyme in nearly dry organic solvent and endow the immobilized lipase with excellent reusability and storage stability. Our present study may widen the application of immobilized enzyme with MOF as the immobilized carrier. Graphical Abstract
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ENVIRONMENTAL RESEARCH
·
2022
·
IF 8.431
Yafei Zhang,Jing Ma,Jiajun Miao,Liang Yue,Mingzhao Cheng,Yi Li,Zhenzi Jing
More efficient soil remediation technologies are highly anticipated to treat large quantities of heavy metal-polluted urban sites nowadays. Herein, a novel hydrothermal technology of converting heavy metal-polluted soils into zeolites for in-situ immobilizing heavy metals was proposed. The zeolites (analcime and cancrinite) could be synthesized hydrothermally with certain Na/Si and Al/Si ratios. The formed zeolites could manage to change their species and structure during zeolitization to accommodate different heavy metals in soil according to their size and charge. Since smaller-size Cu 2+ was introduced, analcime and some cancrinite possessing small cages could be formed adaptively to immobilize the Cu 2+ by replacing Na + and forming Cu 2+ -OH and Cu 2+ -O. Whereas, cancrinite with large channels managed to form to immobilize the larger-size Cd 2+ by forming Cd 2+ -O. Interplanar spacing variation of zeolites also corresponded to their structural change for accommodating different heavy metals. Leaching results showed the amounts of Cu and Cd leached from the synthesized zeolites were reduced to 0.005% and 0.05% respectively, reflecting a more stable immobilization of smaller heavy metals by small cages, in agreement with the results of distribution coefficient ( K d ). Negligible effect of pH environment on the leaching rates further confirmed the stable structural immobilization of heavy metals by zeolites.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
BIOCHEMICAL ENGINEERING JOURNAL
·
2022
·
IF 4.446
Jiacong Wu,Yi Wang,Juan Han,Lei Wang,Chunmei Li,Yanli Mao,Yun Wang
In this work, a mesoporous Zr-based MOF (MP-UIO-66) was first synthesized by biomineralization method using dextran as template and the resultant particles were applied in the immobilization of cellulase . Compared with conventional UIO-66, MP-UIO-66 has more mesoporous channels (4.6 nm) that allow cellulase (3.4 * 12.4 nm) to be entrapped into the channels, improving loading capacity and stability of immobilized enzyme . Specifically, the results showed that MP-UIO-66 had an excellent loading capacity (265 mg g −1 ) for cellulase, and the residual enzyme activity of PVP-cellulase@MP-UIO-66 (PCMU) was still about 83% after 6 cycles. Moreover, the suitable pore structure exposes the active center of cellulase to the external environment, which facilitates the mass transfer of the substrate. Based on Michaelis-Menten constant analysis, the substrate affinity (13.355 mg mL −1 ) and catalytic efficiency (1.311 mL mg −1 min −1 ) of PCMU were better than those of free cellulase (14.525 mg mL −1 , 0.732 mL mg −1 min −1 ).
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2022
·
IF 16.744
Chen Wang,Mingjie Huang,Wei Lou,Wei Xiang,Tao Zhou,Juan Mao,Feixiang Zan,Xiaohui Wu
In-situ removal of Cr(VI) by metallic (oxides) materials is generally limited by rapid loss of surface active sites, especially in neutral water/wastewater circumstances co-existing organic ligands impurity. This study has firstly demonstrated that synthesized magnetic electron-rich copper-iron oxides composites (Cu 2 O-Fe 3 O 4 ) could successfully achieve amazingly efficient reductive immobilization of Cr(VI) induced by common citric ligand (Cit). As Cr(VI) reduced heterogeneously on the composites, immobilization of the generated Cr(III) was almost synchronous via a “spatially-separated” way and correlated linearly with simultaneous dissolved Cu. DFT calculations indicated more appropriate adsorption energy of Cit in realizing its preferential coordination on Fe 3 O 4component surface and Cr(VI) adsorption on Cu 2 O component , as compared to oxalic, tartaric and EDTA ligands. The complexed Cit (Cit≡Fe 3 O 4component ) would promote internal electron transfer from Fe 3 O 4component to Cu 2 O component then adsorbed Cr(VI), causing a highly improved electron efficiency of 72.25%. Most importantly, acting as a regulator of the continuously synchronous reduction and immobilization, Cit≡Fe 3 O 4component would tendentiously chelate newborn Cu(II) at Cu 2 O component surface to release bulk Cu 2+ -Cit complexes, refreshing the reduction sites as well as favoring the Cr(III) immobilization of great stability at the exposed sites of Fe 3 O 4component . This study has revealed that specific impurity ligands can stimulate and tune effective reductive immobilization of heavy metal oxyanions by electron-rich materials under near-neutral conditions, providing a new method towards the efficient treatment of Cr(VI) contaminated wastewaters.
✓ 已验证
产品关联
DOI
高影响因子
ENZYME AND MICROBIAL TECHNOLOGY
·
2022
·
IF 3.705
Liya Zhou,Yaping Ouyang,Weixi Kong,Teng Ma,Hao Zhao,Yanjun Jiang,Jing Gao,Li Ma
In this study, a novel kind of Ni-NTA modified monodispersed SiO 2 nanoflowers (Ni-NTA@SiO 2 nanoflowers) were successfully synthesized. The obtained Ni-NTA@SiO 2 nanoflowers were used to specifically adsorb and purify His-tagged old yellow enzyme (OYE1) and glucose dehydrogenase (GDH), which allows access to optically pure (3 S)− 3-methyl-cyclohexanone through asymmetric hydrogenation reaction, and forms a cofactor regeneration system. The protein loading amount on Ni-NTA@SiO 2 nanoflowers was 40.17 mg/g support and the activity recoveries of OYE1 and GDH were 81.53% and 79.68%, respectively. The effects of pH and temperature on the activity of free and co-immobilized enzymes were investigated, and the stability as well as reusability were also measured. Compared to free enzymes, the co-immobilized enzymes showed higher thermal and storage stability. The co-immobilized enzymes were applied to asymmetric reduction of C C bonds for the synthesis of a chiral center with excellent enantioselectivity (ee > 99%), and the conversion was 46.02% after 7 cycles. This work introduced a one-pot multi-enzyme purification and co-immobilization strategy to construct efficient cofactor regeneration system with high activity and stability.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Frontiers in Bioengineering and Biotechnology
·
2022
·
IF 6.064
Ni Yun,Lv Zhixiang,Wang Zhou,Kang Shouyu,He Dawei,Liu Ruijiang
Magnetic α-Fe2O3/Fe3O4 heterostructure nanosheets were fabricated via hydrothermal calcination. The activity of penicillin G acylase (PGA), which was covalently immobilized onto silica-decorated heterostructure nanosheets, achieved the highest activity of 387.03 IU/g after 18 h of incubation with 0.1 ml of PGA. In contrast, the activity of free PGA reached the highest level when the temperature was 45°C with a pH of 8.0. However, the activity of free PGA changed more dramatically than immobilized PGA as the relative conditions changed. Moreover, the Michaelis–Menten constant (Km) and reusability of immobilized PGA were also explored. The results showed that free PGA Km and maximum rate (Vmax) were 0.0274 M and 1.167 μl/min, respectively. Km and Vmax values of immobilized PGA were 0.1082 M and 1.294 μl/min, respectively. After 12 cycles of repetitive use, immobilized PGA remained approximately 66% of its initial activity, indicating that the PGA immobilized onto the heterostructure nanosheets showed better stability and reusability than free PGA.
✓ 已验证
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）