Analytical Methods
·
2018
·Vol. 10
·期 17
·1986-1992
·
IF 2.073
Shiwei Liu,Tongshun Wu,Fenghua Li,Qixian Zhang,Xiandui Dong,Li Niu
In this study, a low-cost disposable graphene sensor was fabricated for detecting heavy metals such as Cd2+, Pb2+ and Cu2+ by the anodic stripping voltammetry method (ASV). Vacuum compacted graphene films were used as the three electrodes, and they showed excellent conductivity and low noise signals. A big advantage was the simple fabrication process of graphene films without any binder. Furthermore, a ferrocene-based internal reference was introduced in the working electrode. The analytes were recognized by the relative distances of the stripping potential peaks between the working electrode and internal reference electrode. Finally, the all-graphene-based sensor was successfully built for the electrochemical analysis and then applied for determination of heavy metals in real river-water samples.
研究领域:
环境科学
·
分析化学
✓ 已验证
DOI
高影响因子
MICROCHIMICA ACTA
·
2025
·Vol. 192
·期 9
·1-13
·
IF 5.3
Li Zehao,Jing Weixuan,Yang Zhenwei,Gao Weizhuo,Zhou Fan,Han Feng,Mao Qi,Zhao Libo,Yang Zhaochu,Jiang Zhuangde
A low-hysteresis coaxial pH sensor was presented for continuous soil monitoring. The electrolyte was irradiated with ultraviolet (UV) light for different durations, and then used for the electrodeposition of the IrO x film onto the front end of a stainless-steel wire, forming the working electrode. The reference membrane/AgCl/Ag paste (reference electrode) was coaxially integrated onto the insulated middle section of the working electrode, creating the pH sensor. It is found that the UV irradiation treatment generates sufficient hydroxyl radicals in the electrolyte, which increases the proportion of IrO 2 on the surface of the formed IrO x film and further enhances its reversible surface reactions with H + . The reference electrode is reliably integrated with the working electrode, which effectively miniaturizes the pH sensor for soil monitoring. With the UV irradiation duration optimized to be 2 days, the sensitivity and hysteresis voltage of the pH sensor were determined to be -74.8 mV/pH and 3 mV, respectively. The pH sensor maintained a stable potentiometric response even when bent to a 180° angle or subjected to 50 bending cycles. Moreover, the pH values of six soil samples were reliably determined, and the pH variations in a soil sample were monitored over an 11-day testing period. These results benefit accurate and continuous pH monitoring in agricultural and livestock applications. Graphical
研究领域:
传感器
·
电化学
·
土壤科学
·
环境监测
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
·
2022
·Vol. 169
·期 8
·087505
·
IF 4.386
Lin Yang,Chunping Wu,Yiran Zhang,Bang Xiao,Anqi Jiao,Ke Li,Ting Chen,Reggie Zhan,He Lin
A mixed potential ammonia sensor using In2O3 sensing electrode was prepared, and its sensing performance was enhanced by adjusting particle size with calcination heating rate as well as the utilization of NiCo2O4 reference electrode. It was found that the sensor with a calcination heating rate of 2 °C min−1 had the best performance, with a sensitivity of −61.27 mV decade−1 at 525 °C, and the TEM results showed that the average particle size was 70.36 nm. Furthermore, the sensor exhibited good stability against oxygen concentration fluctuation. The results also indicated that the mixed potential has a linear relationship with the logarithm of NH3 concentration, suggesting that the ammonia sensors in this study conform to the mixed potential theory. To address the issue that most ammonia sensors are susceptible to NO2 interference, NiCo2O4 was used as reference electrode to replace the Pt reference electrode, which could greatly offset the response of NO2 and improve the sensors selectivity. In summary, the developed In2O3/YSZ/NiCo2O4 sensor exhibited a great potential for NH3 monitoring in SCR systems.
研究领域:
材料科学
·
电化学
·
环境监测
✓ 已验证
DOI
高影响因子
BIOSENSORS & BIOELECTRONICS
·
2023
·
IF 12.6
Yuan Wang,Yuye Li,Chang Liu,Na Dong,Dong Liu,Tianyan You
The development of accurate and reliable sensor for on-site detection of microcystin-LR (MC-LR), one of hazardous environmental pollutants , is highly required. Herein, a laser induced graphene (LIG)-based electrochemical aptasensor for sensitive on-site detection of MC-LR was reported. LIG electrode, the substrate of aptasensor, was prepared via thermal transfer with ethylene-vinyl acetate copolymer , and LIG acted as quasi-reference electrode to replace conventional Ag/AgCl electrode for better operability and robustness. LIG electrode provided large surface area to assemble tetrahedral DNA to absorb methylene blue (MB) for the signal amplification . For detection, the specific recognition of MC-LR with aptamer led to the stripping of tetrahedral DNA complex and further the decreased redox current of MB (I MB ). Consequently, the fabricated aptasensor offered high analytical performance for MC-LR detection with a linear range of 1 × 10 -2 -1 × 10 5 pM and a detection limit of 3 × 10 -3 pM, which was successfully used for water sample analysis with comparable reliability and accuracy of standard method. Furthermore, a portable detection platform by coupling of LIG-based electrochemical aptasensor with electrochemical workstation was constructed for on-site detection of MC-LR. This work offers a novel method for the on-site monitoring of MC-LR, which promotes the investigation of LIG-based electrochemical biosensing in the field of environmental analysis .
研究领域:
环境分析
·
生物传感
·
分析化学
·
环境科学
✓ 已验证
DOI
高影响因子
TALANTA
·
2024
·
IF 5.6
Tong Ji,Wen Ye,Weiyu Xiao,Graham Dawson,Qiuchen Dong,Christopher Gwenin
Cortisol is a well-known stress biomarker; this study focuses on using electrochemical immuno-sensing to measure the concentration of cortisol selectively and sensitively in artificial samples. Anti-cortisol antibodies have been immobilised on polycrystalline Au electrodes via strong covalent thiol bonds, fabricating an electrochemical bio-immunosensor for cortisol detection. IrO x was then anodically electrodeposited as a reference electrode on a commercial screen-printed electrode and electrochemical impedance spectrometry (EIS) studies were used to correlate the electrochemical response to cortisol concentration and the induced changes in charge transfer resistance (R ct ). A linear relationship between the R ct and the logarithm of cortisol concentration was found in concentrations ranging from 1 ng/mL to 1 mg/mL with limit of detection at 11.85 pg/mL (32.69 pM). The modification of the reference electrode with iridium oxide has greatly improved the reproducibility of the screen-printed electrode. The sensing system can provide a reliable and sensitive detection approach for cortisol measurements.
研究领域:
电化学
·
生物传感器
·
即时诊断
·
分析化学
✓ 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）