Research On Detection Of Antibiotics In Milk Based On Microcavity Fiber SERS Probe

Antibiotic residues in milk mainly come from the unreasonable use of various antibiotics in the breeding process of dairy cows.Long-term consumption of milk containing trace antibiotics will cause certain harm to the human body.Although the existing antibiotic detection methods have high detection accuracy,they have disadvantages such as introducing complicated sample pretreatment,time-consuming and so on.Therefore,this paper studies the surface-enhanced Raman scattering(SERS)technology combined with fiber sensing technology to achieve trace detection of antibiotics in milk.In this paper,the background and significance of the subject research are introduced,and the current status of antibiotic detection and the research status of fiber SERS probe are extensively investigated.A reserach on the detection of antibiotics in milk based on a microcavity optical fiber SERS probe is proposed.The main contents are summarized as follows.Firstly,the enhancement mechanism of SERS and the calculation method of its enhancement factor are described in detail.The sensing principle of fiber SERS probe is explained.Secondly,the preparation and characterization of nano-silver sol substrate and microcavity fiber SERS probe substrate were studied.The experimental system and conditions were introduced.The relationship between the etching time of graded index multimode fiber and the length of microcavity was explored.Two different SERS active substrates were prepared by chemical methods.In addition,they were characterized and analyzed.Thirdly,the performances of different SERS active substrates are explored.The performances of fiber probes with different etching time were tested.The structural parameters of fiber SERS probes were analyzed.And various performances of nano-silver sol substrate and fiber SERS probe substrates were explored and compared,such as sensitivity,reproducibility,stability and so on.The performance of the prepared fiber SERS probe and related literature were compared and analyzed.Finally,the microcavity fiber SERS probe substrate was used to detect the residues of fluoroquinolone antibiotics and ?-lactam antibiotics in milk respectively.The characteristic peaks of enrofloxacin and amoxicillin were attributed and analyzed.The sensitivity,reproducibility and recovery of enrofloxacin and amoxicillin in milk were investigated.The composition of mixed antibiotics in milk is detected and analyzed.