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Published on: September 17, 2017
Aptamer-Based Magnetic Nanoprobe for Quantitative Measurement of Chloramphenicol in Milk through Portable Reader
Hossein Marofi1, Adele Rafati1,2, Pooria Gill1,2
1Department of Medical Nanotechnology, Faculty of Advanced Technologies in Medicine, Mazandaran University of Medical Sciences, Sari, Iran.
Background:
We described here an aptamer-based magnetic nanoprobe for measuring the amount of chloramphenicol (CAP) in milk.
Methods:
The nanoprobe presented in this method consists of a magnetic nanoparticle conjugated to a specific CAP aptamer. If the target is detected in the sample, the nanoprobe binds to it, and the aptamer forms a G-quadruplex structure. This structure mimics the peroxidase activity in the presence of the hemin cofactor. If tetramethylbenzidine is added to the sample containing the nanoprobe, a blue color light is observed. After adding a stop reagent solution, the color produced is measured by a microplate reader and a portable meter.
Results:
This study proves a 99% positive linear relationship between the microplate reader's results and the portable meter results.
Conclusion:
Conjugation of the aptamer to magnetic nanoparticles and applying magnetic separation operations change the nanoprobe performance by 11% for both mentioned devices.

