Synthesis Of AuM(M=Pd,Pt) Nanostuctured Materials And Their Researchs On Electrochemical Sensing Performance

Electrochemical sensor with high sensitivity,good selectivity,ease of operation,low cost and easy miniaturization has been received widespread concerned and great application in the field of medicine,biology,environment analysis and so on.Especially,electrochemical immunosensor has drawn our great attention as a rising star.From metal nanomaterials to carbon-based materials,these novel nanomaterials open a new door for the electrochemical immunosensor.Not only do they have brilliant electrochemical performance,but also the excellent ability of the combination with biological molecules.The novel nanomaterials have irreplaceable advantages that made them stand out from other materials.Owing to their good electrochemical catalytic ability,fast electron transfer rate and great biocompatibility,gold-based noble metal nanomaterials have been the ideal materials to construct electrochemical immunosensor.In this work,three gold-based nanomaterials with different morphology,composite and structure were firstly synthesized using theophylline-7-acetic acid(T7AA),L-proline and 4-aminopyridine(4-AP)as the small molecule capping agent.Then,two electrochemical immunosensors and an electrochemical hydrazine hydrate sensor were introduced with the obtained gold-based nanomaterials.The main research contents are as follows:(1)AuPd alloyed nanochain networks(AuPd NCNs)were prepared by the T7AA-assisted single-step seedless wet-chemical method.The architectures were utilized to construct an enzyme-free sandwich-like immunosensor for ultrasensitive detection of carbohydrate antigenl5-3(CA15-3)and the initially immobilized AuPd NCNs were used as the electrode material,which can incubate primary antibody(Ab1),improve the electron transfer and amplify the signals of the label on second antibody(Ab2)to enhance the selectivity of the immunosensor for the reduction of H2O2.The resulting sandwich-like immunosensor exhibited wide linear range(1 fg mL-1-100 ng mL-1),low detection limit(0.33 fg mL-1),good reproducibility,high stability and sensitivity.This method has potential application value for the clinical detection of CA15-3.(2)Alloyed AuPt nanocalliandras(AuPt NCs)were synthesized by a single-step hydrothermal method in the presence of L-proline.Based on AuPt NCs,a novel label-free carbohydrate antigen 19-9(CA19-9)immunosensor was fabricated accordingly and the K3[Fe(CN)6]was used as the signal source in this case.The as-obtained immunosensor displayed the wide linear range(0.05-50 U mL-1),low detection limit(0.03 U mL-1)and good selectivity.The resulting immunosensor was employed for the electrochemical determination of CA19-9 and explored for the assay of CA19-9 in human serum samples.(3)A simple one-pot aqueous method was developed to synthesize alloyed AuPd nanorod chains(NRCs)in the presence of 4-AP.And we discussed the influence of the concentration of 4-AP to the morphology of AuPd products.The as-obtained nanocrystals were explored to fabricate an electrochemical sensor for hydrazine determination.The resultant sensor exhibited the superior electroanalytical performance,including the wide linear range(0.10-501.00 ?M),high sensitivity,low detection limit(0.02 ?M).