| In recent years,functional silicon nanometer materials have been widely used in the field of biochemistry because of its excellent optical and electrical properties,easy surface modification and biocompatibility.As one kind of silicon nanometer materials,silicon quantum dots?Si QDs?have been widely applied in life analysis and biomedical fields due to its good biocompatibility and low toxicity.In this thesis,silicon quantum dots involved new chemiluminescence and electrogenerated chemiluminescence systems were constructed,andthe potential applications of these systems in biosensoing field were discussed.The main contentsare as follows:1.Herein,ECL behavior of eco-friendly Si QDs was reported in neutral aqueous condition.Stable and intense cathodic ECL emission was obtained in phosphate buffer solution?PBS?with K2S2O8 as coreactant.ECL resonance energy transfer?ECL-RET?system was established with Si QDs ECL as energy donor and gold nanoparticles?Au NPs?as energy acceptor,based on which a novel ECL biosensor was fabricated.The increased ECL signals varied linearly with the target DNA concentrations in the range of 0.1×10-15 mol L-1 to 1×10-12 mol L-1 with the detection limit of 0.016 ×10-15 mol L-1?3??.The proposed ECL sensor exhibited highly sensitivity and good selectivity in the detection of target DNA.2.In the present work,ECL of luminol was reported in neutral Si QDs aqueous solution at gold electrode.The shoulder peak should be result from luminol ECL,which can be enhanced in the presence of Si QDs.The strong ECL emission should be result from ECL-RET between luminol and Si QDs.An ECL aptasensor for the detection of lysozyme was fabricated based on the ECL-RET system.The proposed method showed high sensitivity,good selectivity,and wide linearity for the detection of lysozyme in the range of 5.0×10-11-5.0×10-6 mg m L-1 with a detection limit of 5.8×10-12 mg m L-1?3??.The results suggested that the as-proposed luminol/Si QDs ECL biosensor will be promising in the detection enzyme.3.Weak chemiluminescence?CL?of luminol was obtained in neutral solution in the presence of potassium persulfate?K2S2O8?,which could be apparently enhanced in the presence of Si QDs.The CL system was characterized by CL,FL,UV-vis absorption spectra,which suggested that CL resonance energy transfer?CRET?could occur between Si QDs and luminol.The excited state of Si QDs can act as energy donor and transfer its energy to luminol,resulting in the strong CL emission.Ascorbic acid?AA?exhibited strong inhibiting effect on the CL signal and could be sensitively detected.The proposed method showed wide linearity for the detection of AA in the range of 0.5×10-6 mol L-1 to 10×10-6 mol L-1 with a detection limit of 3.24 ×10-9 mol L-1?3??. |
PDF Full Text Request