Analytical Methods
·
2023
·Vol. 15
·期 24
·2971-2978
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IF 3.1
Muhammad Idrees Khan,Qiang Zhang,Youli Tian,Shah Saud,Yiren Cao,Jicun Ren,Weiwen Liu,Chengxi Cao
Cholesterol (CHO) in human blood is one of the most frequently and crucially quantified substances in diagnostic laboratories. However, visual and portable point of care testing (POCT) methods have been rarely developed for the bioassay of CHO in blood samples. Here, we developed an electrophoresis titration (ET) model, a chip device of ∼60 grams, and a quantification method for the POCT of CHO in blood serum based on a moving reaction boundary (MRB). In this model, the selective enzymatic reaction is integrated with an ET chip for visual and portable quantification. At first, CHO reacted with cholesterol oxidase (CHOx) in the anode well, producing H2O2 and cholest-4-en-3-one in the solution. H2O2 further oxidized the colorless and chargeless leucocrystal violet (LCV) dye into violet colored positively charged crystal violet (CV+) and, under the influence of the electric field, the CV+ migrates in the ET channels and is titrated by the alkali of sodium hydroxide immobilized in the ET channels. The length covered by the MRB was measured as a function of the CHO content. The relevant experiments validated the feasibility of the model and method. Furthermore, the experiments revealed the high selectivity, portability, and visuality of the ET-MRB model, device, and method. Finally, the experiments showed a fair sensitivity of LOD of 5 μM, good linearity of 10–1000 μM (r2 = 0.9919), fair stability (intra-day RSD of less than 5.09% and an inter-day RSD of less than 6.36%), and high recovery (99.4–105%). All the data and results indicate the potential of the ET-MRB model, chip device, and method for POCT of CHO in human blood samples.
研究领域:
医学诊断
·
生物化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2019
·
IF 6.393
Muhammad Idrees Khan,Qiang Zhang,Yuxin Wang,Shah Saud,Weiwen Liu,Shaorong Liu,Hao Kong,Cunhuai Wang,Asad Uzzaman,Hua Xiao,Liu-Yin Fan,Cheng-Xi Cao
Assays of uric acid (UA) in human urine and blood are of great significance to clinic diagnoses of many diseases, such as gout, renal failure, and hyperuricemia. Portable and visual quantification method, however, has been rarely developed for POCT detection of UA in urine and blood samples. In this work, we developed the electrophoresis titration (ET) model, the relevant sensing method and the portable chip device for portable and visual detection of UA in both urine and blood based on moving reaction boundary (MRB). In the model, uricase catalyzes UA in the anode well to allantoin, producing hydrogen peroxide, which oxidizes leucocrystal violet dye without charge to crystal violet (CV + ) with one positive charge. Under an electric field, a MRB was created between the violet CV + moving from the anode well into the channel and the alkaline sodium acetate in channel, resulting in an ET sensing. The model indicated that the distance of MRB under given conditions was as a function of UA content, implying an extraordinary simple sensing for UA. Based on the MRB-ET model, a series of experiments were conducted. The results evidently validated the model and method of ET-MRB. The experiments not only demonstrated the high facility and portability of MRB-ET model, but also showed the visuality, selectivity and rapidity. In addition, the experiments revealed the fair sensitivity (<0.1 mM), linearity (0.1–4.0 mM, r 2 = 0.9948), recovery (85%–106%) and stability (RSD 3.8–7.1%). Finally, the developed method was successfully used for the determination of UA both in urine and blood. All these results manifested the simple, portable and visual sensing of UA in human body fluid samples, and implied the potential of MRB-ET method to real POCT assay of UA in urine and blood samples.
研究领域:
生物化学
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医学诊断
·
分析化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF SEPARATION SCIENCE
·
2016
·Vol. 40
·期 3
·789-797
·
IF 2.741
Liangfei Ouyang,Qian Liu,Heng Liang
A common drawback of paper-based separation devices is their poor detection limit. In this study, we combined field-amplified sample stacking with moving reaction boundary electrophoresis on a paper chip with six array channels for the parallel separation and concentration of multiple samples. With a new hyphenated technique, the brown I 2 from the Fe 3+ /I − oxidation–reduction reaction emerged near the boundary between the dilute ethylene diamine tetraacetic acid and potassium iodide and highly concentrated KCl solutions. For the separation and concentration of three components, Cr 3+ , Cu 2+ , and Fe 3+ , the Fe 3+ detection limit was improved at least 266-fold by comparing the hyphenated technique with moving reaction boundary electrophoresis. The detection limit of Fe 3+ was found to be as low as 0.34 ng (20 μM) on the paper chip. We also demonstrated the analysis of a real sample of four metal ions, with detection limits as follows: 0.16 μg Cr 3+ , 1.5 μg Ni 2+ , 0.64 μg Cu 2+ , and 1.5 μg Co 2+ . The synergy of field-amplified sample stacking and moving reaction boundary electrophoresis in the micron paper-based array channels dramatically improved the detection limit and throughput of paper-based electrophoresis.
研究领域:
分析化学
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环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ANALYTICAL AND BIOANALYTICAL CHEMISTRY
·
2013
·Vol. 405
·期 26
·8587-8595
·
IF 3.659
Tang Yun-Yun,Wang Hou-Yu,Chen Lu,Li Si,Guo Chen-Gang,Fan Hui-Zhi,Cao Cheng-Xi,Fan Liu-Yin
We developed a novel polyacrylamide gel electrophoresis (PAGE) method to stack and separate human hemoglobins (Hbs) based on the concept of moving reaction boundary (MRB). This differs from the classic isotachophoresis (ITP)-based stacking PAGE in the aspect of buffer composition, including the electrode buffer (pH 8.62 Tris–Gly), sample buffer (pH 6.78 Tris–Gly), and separation buffer (pH 8.52 Tris–Gly). In the MRB-PAGE system, a transient MRB was formed between alkaline electrode buffer and acidic sample buffer, being designed to move toward the anode. Hbs carried partial positive charges in the sample buffer due to its pH below p I values of Hbs, resulting in electromigrating to the cathode. Hbs would carry negative charges quickly when migrated into the alkaline electrode buffer and be transported to the anode until meeting the sample buffer again. Thus, Hbs were stacked within a MRB until the transient MRB reached the separation buffer and then separated by zone electrophoresis with molecular sieve effect of the gel. The experimental results demonstrated that there were three clear and sharp protein zones of Hbs (HbA 1c , HbA 0 , and HbA 2 ) in MRB-PAGE, in contrast to only one protein zone (HbA 0 ) in ITP-PAGE for large-volume loading (≥15 μl), indicating high stacking efficiency, separation resolution, and good sensitivity of MRB-PAGE. In addition, MRB-PAGE was performed in a conventional slab PAGE device, requiring no special device. Thus, it could be widely used in separation and analysis of diluted protein in a standard laboratory.
Diagram of MRB-induced stacking in a slab PAGE. ( A ) arrangement of separation buffer (pH 8.01–9.55 Tris–Gly), sample buffer (pH 6.37–7.22 Tris–Gly), and electrode buffer (pH 8.21–9.05 Tris–Gly); ( B ) initial MRB formed between electrode and sample buffers for stacking of low-content Hbs in sample buffer under electric field; ( C ) MRB moving toward the anode and partly stacking of Hbs within the MRB; ( D ) quasi-complete stacking of Hbs via MRB closing to the separating gel; ( E ) separation of Hbs in a zone electrophoresis mode
研究领域:
生物化学
·
医学检测
·
蛋白质分析
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2022
·
IF 6.371
Xiao Chen,Senran Hao,Tengda Lu,Mian Li,Lina Han,Peng Dong,Jie Xiao,Xiaoyuan Zeng,Yingjie Zhang
Direct carbon solid oxide fuel cell (DC-SOFC) is a potential and prospective technology to convert chemical energy from real-world coal fuels into electricity with environment friendliness and high efficiency. However, the limited three-phase reaction boundaries and the challenge of sluggish carbon oxidation activity have always hindered the development and application of DC-SOFCs. On this account, here vanadium-doped B-site-deficient La 0.5 Sr 0.5 FeO 3-δ (LSFV x , x = 0, 0.05, 0.10, 0.15) perovskite materials are synthesized and developed as the anode of DC-SOFCs for brown coal utilization. The best electrochemical performance at 850 ℃ belongs to the LSFV 0.1 cell, delivering a maximum power density of 249 mW cm −2 , and the lowest polarization resistance of 0.37 Ω cm 2 ,along with the longest discharging time up to 8.65 h. Compared with the pure LSF, the electrochemical performances of all perovskites doped with vanadium have been greatly promoted, demonstrating that the doping of vanadium can effectively expand the three-phase reaction boundaries of the cell, thus enhance the catalytic activity due to the promotion of oxygen deficiencies and tailing of electronic structures.
研究领域:
能源材料科学
·
环境工程
✓ 已验证
产品关联
DOI
高影响因子
CEMENT & CONCRETE COMPOSITES
·
2023
·
IF 10.5
Shujun Li,Gaofeng Chen,Yasong Zhao,Zhenhai Xu,Xu Luo,Cheng Liu,Jianming Gao
Knowing the reactivity of recycled brick powder (RBP) is fundamental for its correct and efficient utilization. In this work, the dissolution behavior of RBP in NaOH solution and the degree of reaction in cement matrix were studied to investigate the reactivity of RBP. The results revealed that the main active species of RBP, Si and Al, showed obvious lasting dissolution with a significant non-steady state dissolution stage, indicating that the reaction proceeds slowly. The dissolution mechanism controlled by the phase boundary reaction, with activation energies of 82.74 kJ/mol and 75.79 kJ/mol for Si and Al dissolution, respectively, further confirmed this finding. The strength activity index, thermogravimetric analysis , selective dissolution, BSE-IA-Mapping and MAS NMR all confirmed reactivity of RBP. Additionally, reaction rims were observed around RBP particles in cement paste . The low Ca/Si and Ca/Al ratios and their significant increases in a direction from the particle boundary to the paste demonstrate that the rim was a hybrid phase composed of the original RBP components and the reaction products.
研究领域:
材料科学
·
土木工程
·
化学工程
✓ 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）