ORGANIC & BIOMOLECULAR CHEMISTRY
·
2018
·Vol. 16
·期 31
·5667-5676
·
IF 3.423
Li Huang,Ying-Juan Cao,Xiang-Ying Sun,Bin Liu,Jiang-Shan Shen
Extending the research on 3,3′,5,5′-tetramethylbenzidine (TMB) and its derivatives in analytical chemistry is important, considering that TMB is widely used as an enzyme catalytic substrate. In this work, two TMB derivatives, TMBS and TMBB, were synthesized via a facile and one-step condensation reaction between the –NH2 group of TMB and the –CHO group of salicylaldehyde or benzaldehyde. Because at low pH the two Schiff base compounds can release TMB which can emit strong fluorescence, the probes could show dual-modal signal responses, fluorescence and UV-vis absorption, towards the pH. Practical applications of pH sensing in Chinese rice vinegar and lemon juice samples were successfully demonstrated. On the basis of these findings, a catalytic chromogenic reaction was developed to monitor the pH with the naked eye, too. Furthermore, considering the chemical equilibrium reaction between CO2 and H2O and that glucose oxidase (GOD) can catalyse the dehydrogenation and oxidation reaction of β-D-glucose to produce gluconic acid, both of which can result in lowering the pH values of the two Schiff base systems, highly sensitive and selective dual-modal sensing systems for detecting CO2 and β-D-glucose have also been successfully established. Therefore, the two synthesized TMB derivatives can demonstrate their robust application potential.
研究领域:
分析化学
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生物传感
·
酶催化反应
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MICROCHEMICAL JOURNAL
·
2025
·
IF 5.1
Duoduo Zhang,Xinyu Zhang,Mingshuang Liang,Xiuxiu Li,Nan Wang,Heping Xiao,Dawei Cao,Xiubo Zhao
Escherichia coli ( E. coli ) is one of the most prevalent foodborne pathogens, releasing toxic substances and causing infectious and life-threatening diseases. Thus, the rapid and sensitive detection of E. coli is essential for safeguarding human health. Herein, a ratiometric colorimetric sensor was constructed for detecting E. coli , utilizing the coordination between zirconium (Zr)-tetraphenylporphyrin tetrasulfonic acid (TPPS) hydrate metal–organic frameworks (Zr-TMs) and copper ions (Cu 2+ ). E. coli can capture and convert external Cu 2+ into Cu + through its distinctive metabolic activities. This capability further enhances the coordination interaction between the porphyrin ligands in Zr-TMs and the metal ions. As a result, the ultraviolet–visible (UV–vis) absorption spectral properties of Zr-TMs changed, exhibiting an enhanced absorption peak at 413 nm (A 413 ) and a weakened peak at 434 nm (A 434 ). By monitoring the increase in ratio of A 413 to A 434 , this sensor achieved rapid and sensitive detection of E. coli at concentrations ranging from 10 2 to 10 7 CFU/mL within 63 min, with a detection limit of 19 CFU/mL. The color of the solution gradually changed from green to colorless. This proposed ratiometric method utilized the opposite changes in the two UV–vis absorption peak signals (A 413 and A 434 ) generated by the Zr-TMs probes, improving detection accuracy and achieving visual analysis. Additionally, this method accurately identified E. coli in milk samples, demonstrating substantial potential for detecting pathogenic bacteria in food.
研究领域:
食品安全检测
·
微生物学
·
分析化学
✓ 已验证
产品关联
DOI
高影响因子
Optoelectronics Letters
·
2014
·Vol. 10
·期 3
·164-167
·
IF 0
Yang Ai-ling,Li Shun-pin,Wang Yu-jin,Bao Xi-chang,Yang Ren-qiang
By adjusting pH values of reactant system, the mass ratio of stabilizer/water and aging temperature, size controllable spherical silver nanoparticles (NPs) were synthesized. The properties of silver NPs are characterized by X-ray diffraction (XRD), transmission electron microscope (TEM) and ultraviolet visible (UV-VIS) absorption spectra. Within the pH values of 7.0–11.0, the aging temperature of 80 °C is better to improve silver NPs in shape to nearly sphere, concentrate size distribution and reduce aggregation than the aging temperature of 25 °C. The shape and dispersibility of silver NPs are the best when the pH of the reactant system is within 7.0–8.0. With pH of 7.5, aging at 80 °C, and stabilizer/water mass ratio of 1%, the spherical silver NPs with sizes of 50–70 nm were synthesized. The results are promising to be used to synthesize core/shell NPs when silver NPs are as core.
研究领域:
纳米技术
·
材料科学
·
化学
✓ 已验证
产品关联
DOI
Nanoscale
·
2022
·Vol. 14
·期 45
·16893-16901
·
IF 8.307
Hai Zhong,Hongfang Yang,Jiaqi Shang,Biao Zhao,Jianping Deng
Micro/nanoparticles with surface microstructures have attracted tremendous attention due to their fascinating structures and properties. Herein, we present the first strategy for producing optically active polymer particles with varying surface microstructures via a template surface modification process in which achiral particles act as the template and helical substituted polyacetylene acts as the chiral component. To prepare the designed chiral-functionalized particles, template particles were first reacted with propargylamine to produce alkynylated template particles. The alkynylated templates further participated in the polymerization of chiral alkyne monomers through a surface grafting precipitation polymerization approach, resulting in achiral particles with surface microstructures covalently bonded with a chiral helical polymer. SEM images ascertain the production of chiral-functionalized particles showing various shapes (jar-like, golf ball-like, and raspberry-like particles). Furthermore, CD and UV-vis absorption spectra demonstrate that the grafted polyacetylene chains adopt a predominantly single-handed helical conformation, thereby affording composite particles with optical activity. Using the established protocol, numerous advanced chiral-functionalized micro/nanostructures are expected to be designed and constructed.
研究领域:
材料科学
·
高分子化学
·
纳米技术
✓ 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）