Development Of TTF-TCNQ/IL-modified Electrochemical Sensor And Its Application In Tyrosine Detection

Objective: Development of tetrathiofulvalene tetracyanoquinone/Ionic liquid(TTF-TCNQ/IL)modified electrochemical sensor and its application in tyrosine detection.Method: 1.According to the mechanism of interaction between tetrathiofulvalene tetracyanoquinone(TTF-TCNQ)and different types of ionic liquid(IL),the best IL species were screened by electrochemical method,and tetrathiofulvalene tetracyanoquinone/1-butyl-3-methylimidazolium(TTF-TCNQ/[BMIM][PF₆])conducti ve gel was prepared.A modified TTF-TCNQ/[BMIM][PF₆] electrochemical sensor(TTF-TCNQ/[BMIM][PF₆]/SPE)was prepared by modifying screen printed electrodes(SPE)with appropriate amount of TTF-TCNQ/[BMIM][PF₆] conductive gel.TTF-TCNQ/[BMIM][PF₆]/SPE was characterized by scanning electron microscope(SEM),and the electrochemical behavior of TTF-TCNQ/[BMIM][PF₆]/SPE was investigated by cyclic voltammetry.2.The prepared TTF-TCNQ/[BMIM][PF₆]/SPE was tested by cyclic voltammetry and square wave voltammetry.TTF-TCNQ/[BMIM][PF₆]/SPE was tested in terms of stability,reproducibility and anti-interference ability.The linear range between response current and tyrosine concentration,as well as the minimum detection limit of tyrosine were calculated.The developed tyrosine sensor was used for the determination of real samples and the recovery of tyrosine was calculated.Result: 1.The selection of IL plays a key role in the preparation of TTF-TCNQ/ IL/SPE,and the optimal IL is [BMIM][PF₆].TTF-TCNQ/[BMIM][PF₆]/SPE has good electrochemical properties.2.Under the optimal experimental conditions,TTF-TCNQ/[BMIM][PF₆]/SPE was used to detect tyrosine.Oxidation peak current has a good linear relationship with the concentration of tyrosine in the range of 1.0×10^-7?2.0×10^-5 mol/L,and the minimum detection limit of tyrosine is 0.4×10^-7mol/L. TTF-TCNQ/[BMIM][PF₆]/SPE was used to detect the actual samples,and a better recovery rate was obtained.Conclusion: TTF-TCNQ/[BMIM][PF₆]/SPE developed by electrochemical method.The sensor has the characteristics of fast detection speed and good stability.It can detect tyrosine in samples and artificial urine.