A sensitive carbendazim (CBZ) electrochemical sensor was designed by using Super-P carbon (SPCN) black@zeolitic-imidazolate-framework-8 (SPCN@ZIF-8) nanocomposite modified glassy carbon electrode (SPCN@ZIF-8/GCE). SPCN with pearl-chain nanostructure presented an integrated highly conductive carbon network, which significantly improved the charge transfer efficiency. ZIF-8 nanoparticles possessed high porosity and large specific surface area, which helped to realize the increasement of adsorption ability and accumulation capacity towards CBZ. Moreover, SPCN with excellent conductivity property not only inhibited the agglomeration of ZIF-8 nanoparticles but also compensated the non-conductive property of ZIF-8 nanoparticles. The functional integration of SPCN and ZIF-8 nanoparticles remarkably enhanced the electrochemical detection performance of the SPCN@ZIF-8/GCE sensor towards CBZ. A simple and sensitive CBZ detection could be achieved at the fabricated SPCN@ZIF-8/GCE sensor with low limit of detection of 7.79 nM (CBZ concentration: 0.01–30 μM). Moreover, the fabricated sensor showed good repeatability, reproducibility, and anti-interference performance. When used for the analysis of CBZ in real samples (tomato juice and apple juice), the SPCN@ZIF-8/GCE sensor showed good CBZ detection performance with acceptable recoveries of 99.1%–102.6% and low RSD values of 2.21%–3.27%. This work demonstrated that the SPCN@ZIF-8/GCE sensor may be a promising sensing platform for the rapid and sensitive detection of CBZ residue.
Yong Han,Hui Wang,Ying Yu,Weixia Yang,Fei Shang,Zhonghong Li
Nano-hybrid carbon dots (CDs) with multiple emissions always endure fluorescence quenching induced by the interactions of chemical groups between hybrid CDs and nanomaterial, the samples with abundant interferences by an ordinary pretreatment. Lanthanide ion (DPA-Tb) was employed to hybridize PAN-CDs for the fabrication of ratiometric fluorescent sensor (PAN-CDs&DPA-Tb) to detect Carbendazim (MBC) in complicated food samples with facile pretreatment. The impacts of hybridization on the fluorescence of PAN-CDs were evaluated through dynamic characterizations, which manifested that DPA-Tb and the sensing matrix had no significant influence on the ratiomeric fluorescence of PAN-CDs&DPA-Tb sensor. The sensor (F 363 /F 544 ) linearly responded to concentrations of MBC in 0–0.091 mmol/L with a limit of detection (LOD) of 3.0 × 10 -3 μmol/L and satisfactory applications with recoveries of 92.22–106.08% and RSDs of 0.14–1.69%. The strategy provides a novel sight to investigate the fabrication of CDs-based ratiometric fluorescent sensors.
Yang Dong,Li Xuhua,Li Xiangyu,Chen Jifan,Zhang Ting,Lian Ting,Wang Haihua
Carbendazim (CBD) is widely used as a fungicide that acts as a pesticide in farming to prevent crop diseases. However, CBD can remain on crops for a long time. When consumed by humans and animals, it produces a range of toxic symptoms and poses a serious threat to their health. Therefore, the detection of CBD is necessary. Traditional assay strategies for CBD detection, although sensitive and practical, can hardly achieve fast, robust monitoring during food processing and daily life. Here, we designed a novel electrochemical sensor for CBD detection. In this method, iron oxyhydroxide nanomaterial (β-FeOOH) was first prepared by hydrothermal method. Then, a molecularly imprinted polymer (MIP) layer was electropolymerized on the surface using CBD as the template and resorcinol (RC) as the functional monomer. The synergistic interaction between β-FeOOH and MIP endows the MIP/β-FeOOH/CC-based electrochemical sensor with high specificity and sensitivity. Under optimal conditions, the MIP/β-FeOOH/CC-based sensor showed a wide linear range of 39 pM–80 nM for CBD and a detection limit as low as 25 pM. Therefore, the as-prepared sensor can be a practical and effective tool for pesticide residue detection. Graphical abstract
Pesticide residues like carbendazim have always been a great threat to agricultural production and food safety. Herein, a fluorescent aptasensor for carbendazim detection was established based on aptamer-mediated quenching of gold nanoparticles (AuNPs) toward carbon dots (CDs). CZ-13 aptamer can wrap AuNPs and make them dispersed in salt solution, thus quench the fluorescence of CDs. On adding carbendazim, the aptamer is firstly consumed to preferentially combine with pesticides, resulting in the fluorescence recovery of CDs from quenching status. The degree of fluorescence recovery is positively correlated with pesticide concentration, which enables us to establish a fluorescence aptasensor for carbendazim detection. Under optimal conditions, the limit of detection of the fluorescent aptasensor is determined as low as 2.3 μg·L −1 . Moreover, the average recovery range of carbendazim in several vegetables and fruits is from 86 % to 99 %, indicating that such aptasensor may have bright application prospects for carbendazim detection in foods .