Detection Of Cucurbitacin E Concentration Based On Cell Amplified Surface Plasmon Resonance Technology

Surface Plasmon Resonance(SPR) is a physical optical phenomenon which occurs on the surface between the metal and the dielectric. It is very sensitive to the change of the refractive index close to the metal film. Due to its high sensitivity, fast detection speed, label-free, real-time dynamic monitoring, simple pretreatment, portability and other advantages, SPR technology has been widely used in medical diagnosis, drug screening, food safety and environmental monitoring. In the treatment of cancer, the detection of drug concentration is very important, such as Cucurbitacin E(Cu E). Cu E is a highly oxidized triterpenoid compound isolated from Cucurbitaceae plants that have been used as anticancer, anti-viral, hepatoprotective, and anti-inflammatory medicines for centuries. However, improperly used, it will cause side effects to the human body. Traditionally, we generally use high performance liquid chromatography(HPLC) for the determination of Cu E concentration. But the application of HPLC is limited due to expensive instrument equipment, complex operation, and time consuming. Therefore, we demonstrate a method based on cell amplified SPR technology to detect the concentration of Cu E. The experiments illustrates that the SPR sensor based on this design can achieve a detection limit of 0.774 n M, the detection limit of the sensor is greatly improved, which has achieved ultra-low concentration detection of Cu E. The practical work is as following:Firstly, this part mainly introduced the design, fabrication and characterization of the prism SPR sensor and side polished fiber, and the gold film sensor and the silver film sensors are compared and analyzed in its performance and chemical properties. As a result, in this study we select gold film as the SPR sensor chip.Secondly, part of this paper mainly introduced the cell modification of SPR sensor chip. In order to study the detection of Cu E, the solution of 0n M, 40 n M, 60 n M, 80 n M and 100 n M Cu E were prepared.Thirdly, the main task in this part focuses on study concerning the detection of Cu E concentration based on cell amplified surface plasmon resonance technology. And we observed morphological changes of He La cells treated with different concentrations of Cu E, which illustrates the mechanism of cells enhance SPR signal.The innovation of this paper lies in:A new method to enhance the SPR signal is proposed to achieve the detection of ultra-low concentration Cu E. In the study, we propose that the gold surface of SPR sensor was modified by seeded He La cells onto the sensor surface, fabricating the signal amplification strategy to achieve a detection of 0.774 n M.