Study On The Application Of Electrochemical Sensor Based On Silica Nanochannel Material In Drug Detection

Objective:（1）Based on mesoporous silica nanochannels material（MSN）,a simple,fast,highly sensitive and low-cost electrochemical sensor was prepared for the rapid detection of tanshinoneⅡA（TSN-ⅡA）and cryptotanshinone（CTSN）in blood samples based on the extraction and enrichment of lipophilic drugs by surfactant micelles in the nanochannel.（2）The charge selectivity of MSN material was used to enrich the luminescent molecule Ru（bpy）₃²⁺into the nanochannels.Combined with the advantages of the pattern electrode array and multiple parallel microchannels,a visual electrochemical luminescence（ECL）sensor array with rapid detection and high-throughput was constructed by utilizing the oxytetracycline（OTC）electrochemical luminescence inhibition effect.It is also used for the quantitative detection of OTC in milk samples.Methods:（1）The CTAB@MSN/ITO electrode was synthesized on Indium tinoxide coated glass（ITO）by st?ber solution growth method.The MSN was characterized by Cyclic voltammetry（CV）,and the extraction and enrichment of TSN-ⅡA and CTSN were performed by CTAB micelles.The trace detection of TSN-ⅡA and CTSN in natural medicines was realized by Differential pulse voltammetry（DPV）.（2）The ITO electrode array with interfinger pattern was obtained by UV lithography,and the elastic channels of PDMS with 6 parallel controls were prepared in the same way.An interfinger pattern Ru@MSN/ITO electrode array was prepared by attractting Ru（bpy）₃²⁺,a positively charged luminescent molecule,into the MSN nanomaterial channel by electrostatic interaction.Combining the advantages of patternized electrode array and multi-channel microchannel,a visualized electrochemical luminescence sensor array was constructed for the quantitative detection of OTC in milk samples according to the strategy of OTC quenching the ECL of Ru（bpy）₃²⁺-coreactant system.Results:（1）Under the conditions of optimal electrolyte solution and enrichment time,when the concentration of TSN-ⅡA was in the range of 0.005～1?M and CTSN was in the 0.01～1?M,current intensity of electrochemical sensor and sample concentration has good linear relationship between two pieces.At the same time,detection limit of TSN-ⅡA was 0.0014?M;and the detection limit of CTSN is 0.0019?M.（2）Under the best driving voltage,the electrochemical luminescence OTC visual sensor detection limit was 0.26?M,and the sample consumption was less than 10?L.Six parallel experiments and 36 detection sites were obtained in one experiment,and the detection time was less than 1.5 min.Conclusion:Two electrochemical sensors proposed in this study have the advantages of simple fabrication,high sensitivity and low cost,and have shown application value in clinical detection,rapid detection of food or drugs.