Development of an Electrochemical Aptasensor for Ultrasensitive Detection of Tetracycline in Eggs

In recent years, in order to prevent the occurrence of various diseases, the fncscrambled misuse of antibiotics is quite serious, and the residues of antibiotics such as tetracycline in eggs can also cause damage to human health. A double-stranded DNA probe modified with ferrocene was immobilized onto a gold nanoparticle modified substrate. Tetracycline was added to form a strong affinity binding between the target and the aptamer. During this process, the complementary strand was detached from the electrode surface. Therefore, the measured electrical signal attenuates with the emergence of the target. The linear response of tetracycline concentration to the signal ranged from 0.0005μM~50μM. The fabricated biosensor showed excellent selectivity. The accurate detection limit can be as low as 0.5 nm. Further, in the determination of tetracycline concentrations in water and egg samples, the fabricated biosensor showed excellent selectivity. Furthermore, the applicability of the developed sensor was demonstrated in the determination of tetracycline concentrations in egg samples. The spiking recoveries ranged from 96.18% to 102.75% which reached acceptable level. This detection sensor is simple, time-saving, selective and efficient, which can provide potential services in food production safety, environmental detection and so on.