Determination Of Trace Amounts Of Bisphenol A And Dopamine Based On Graphene Nanomaterials

As a kind of substance which can be used for prevention,treatment and diagnosis of diseases,the quality of medicines is closely related to human life and health.The related research of drug analysis is an important subject direction for the control and research of drug quality.With the increasing awareness of people’s health,the increasing of variety of drugs and the improvement of the requirements for drug analysis,the object of drug analysis becomes more and more complex,and the analysis task becomes more and more difficult.Existing pharmaceutical analysis techniques and methods have gradually failed to meet the urgent needs of drug quality control and pharmaceutical analysis in actual samples,especially for the detection of trace pharmaceutical components in complex matrix samples,so it is urgent to find a new way out.In recent years,with the progress of nanotechnology,the application of new analytical techniques and methods based on nanomaterials in the analysis of complex matrix samples has attracted extensive attention,and good progress has been made in many fields,such as drug analysis,biological analysis and environmental analysis.Based on this,in order to detect trace components in drug-related complex matrix samples,new graphene and its nanocomposites were prepared,and new detection technologies and methods for drug-related samples were constructed.We have carried out the following two aspects of research work:1.Sensitive detection of trace amounts of bisphenol A in silicone rubber packaging materials based on graphene solid phase extraction and capillary electrophoresisGraphene nanomaterials with excellent surface properties were prepared and used as solid phase extraction(SPE)adsorbent to prepare graphene based SPE columns.Using the prepared graphene-based SPE column to efficiently enrich bisphenol A(BPA),combined with the highefficiency detection capability of capillary(CE)technology,an SPE-CE analysis method was constructed.Through optimization experiments,the optimal extraction conditions and optimal CE detection conditions of the prepared graphene-based SPE column for BPA were obtained.Under optimal conditions,compared with commercial SPE column,the constructed SPE-CE combined analysis method shows a good linear relationship for BPA in the range of 0.05-80μg/m L,and the detection limit can reach 0.02 μg/m L(SN=3σ).In addition,methanol ultrasonic extraction and pure water reflux extraction were used to extract trace BPA from the actual sample of baby pacifier with the same material as the silicone rubber package for medicine,and then the migration of BPA in the actual sample was determined by SPE-CE.The method exhibits good accuracy and precision,and can realize the high sensitivity and rapid detection of trace BPA in actual silicone rubber packaging samples.Therefore,the combined method proposed in this paper provides a new idea for the analysis of trace components in drug contact materials,and has broad application prospects.2.Electrochemical sensor for simultaneous detection of dopamine,ascorbic acid and uric acid based on nano-gold-polyethyleneimine functionalized graphene complexPolyethyleneimine functionalized graphene(PEI-G)was prepared by one-step reduction and functionalized graphene oxide,and then gold nanoparticles(Au NPs)are introduced as an electrochemical substrate through layer-by-layer assembly.The results show that the prepared PEI-G/Au NPs substrate combines their advantages,not only has good functionality and bioaffinity,but also has high electrochemical catalytic activity,which can synergistically electrocatalytic effect on ascorbic acid(AA),dopamine(DA)and uric acid(UA).Under optimal conditions,there is a good linear relationship between the current of the sensor and concentration when the concentration of AA is 0.1～55.5 μM,the concentration of DA is 0.1～5.5μM and 5.5～45.5 μM,and the concentration of UA is 0.03～3.55 μM.The detection limit(S/N=3)were calculated to be 0.077 μM,0.068 μM and 0.009 μM,respectively.The designed electrochemical sensor exhibits good selectivity and stability,and can be used for the simultaneous determination of three analytes in actual serum samples with satisfactory results.It provides a simple and reliable technique for the simultaneous detection of AA,DA and UA in biological samples.