A novel and sensitive fluorescence immunoassay for the detection of fluoroquinolones in animal-derived foods using upconversion nanoparticles as labels

2015 ◽  
Vol 407 (28) ◽  
pp. 8487-8496 ◽  
Author(s):  
Gaoshuang Hu ◽  
Wei Sheng ◽  
Yan Zhang ◽  
Xuening Wu ◽  
Shuo Wang
2018 ◽  
Vol 10 (44) ◽  
pp. 5313-5320 ◽  
Author(s):  
Wei Sheng ◽  
Wenxia Duan ◽  
Yingjie Shi ◽  
Qing Chang ◽  
Yan Zhang ◽  
...  

NaYF4:Yb/Tm upconversion nanoparticles-based fluorescence immunoassay in combination with magnetic separation for detecting bisphenol A in drinking and river water samples.


Sensors ◽  
2021 ◽  
Vol 22 (1) ◽  
pp. 8
Author(s):  
Xufang Huang ◽  
Wei Sheng ◽  
Haonan Chen ◽  
Biao Zhang ◽  
Na Huang ◽  
...  

A competitive fluorescence immunoassay for the quantitative detection of 2-amino-3-methylimidazo [4, 5-f] quinoline (IQ) in pan-fried meat patties was developed, using magnetic nanoparticles coupled with coating antigen as the capture probe and anti-IQ antibody coupled with NaYF4: Yb, Er upconversion nanoparticles as the signal probe. Under optimal conditionals, the wide detection range for IQ in phosphate buffer saline is from 0.01 to 100 μg·L−1 (R2 = 0.991) with a detection limit of 0.007 μg·L−1. This proposed method has been applied to detect IQ in two different types of pan-fried meat patties at varying frying times, and the IQ content in chicken patties and fish patties are 2.11–3.47 μg·kg−1 and 1.35–2.85 μg·kg−1, respectively. These results are consistent with that of the ultraperformance liquid chromatography-tandem mass spectrometry. In summary, this method can serve as a sensitive and specific test tool for the determination of IQ in processed meat.


Nanoscale ◽  
2020 ◽  
Vol 12 (14) ◽  
pp. 7875-7887 ◽  
Author(s):  
Ying Lan ◽  
Xiaohui Zhu ◽  
Ming Tang ◽  
Yihan Wu ◽  
Jing Zhang ◽  
...  

A near-infrared (NIR) activated theranostic nanoplatform based on upconversion nanoparticles (UCNPs) is developed in order to overcome the hypoxia-associated resistance in photodynamic therapy by photo-release of NO upon NIR illumination.


2019 ◽  
Vol 13 (1) ◽  
pp. 137-145 ◽  
Author(s):  
Tzonka Godjevargova ◽  
Zlatina Becheva ◽  
Yavor Ivanov ◽  
Andrey Tchorbanov

Objectives: Staphylococcus aureus is a Gram-positive microorganism. S. aureus can grow in various foods and cause food poisoning by secreting enterotoxins. The most common enterotoxins involved in food poisoning are staphylococcal enterotoxin A and staphylococcal enterotoxin B, but Staphylococcal Enterotoxin A (SEA) is predominant. The main types of food contaminated with SEs are meat and meat products, poultry and eggs, milk and dairy products. The aim of this study was to develop a rapid and sensitive fluorescence immunoassay for detection of staphylococcal enterotoxin A in milk. Methods: Monoclonal and polyclonal antibodies for SEA were produced and characterized. Competitive fluorescence immunoassay based on Magnetic Nanoparticles (MNPs) was performed and optimized. MNPs were used as a solid carrier of the antibodies. The first step of the assay was immunoreaction between the immobilized antibody onto MNPs and SEA in milk sample. Then the fluorescein-SEA conjugate was added to the sample. Thus, competitive immunoreaction between MNP-mAb/MNP-pAb with SEA and SEA-FITC was performed. These immuno-complexes were separated by a magnetic separator and the obtained supernatants were analyzed. The fluorescent signal from the excess of conjugated SEA was proportional to the SEA contained in the milk. The assay duration was only 30 min. Results: The fluorescence immunoassays performed with polyclonal antibody had linear ranges from 5 pg/mL to 100 ng/mL SEA in a buffer, and from 50 pg/mL to 50 ng/mL SEA in spiked milk samples. While the same assays performed with monoclonal antibody had linear ranges from 1 pg/mL to 20 ng/mL SEA in buffer, and from 10 pg/mL to 10 ng/mL SEA in spiked milk samples. The detection limits of the developed immunoassays performed in milk were: 48 pg/mL with polyclonal antibody and 9 pg/mL with monoclonal antibody. Conclusion: A rapid and sensitive fluorescence immunoassay based on magnetic nanoparticles with a polyclonal and monoclonal antibody for determination of staphylococcal enterotoxin A in milk was developed.


Sign in / Sign up

Export Citation Format

Share Document