The Development Of A Self-Ranged Droplet Array And Its Application In Bioanalysis

The interaction of materials mainly occurs in the material interface,however,the direct applications of unpredicted surface have limitations in some fields,such as cross-contamination.unbiocompatibility and etc.Therefore,the generation of property-controllable surface is very important.Surface patterning is one of the approaches for surface functionalization of great significance for the development of modern science and technology.Patterned surfaces have several properties,such as superhydrophobicity,self-cleaning effect,self-enrichment effect and so on.Herein,fabrication of microarray biosensor of superhydrophilic microspots separated by superhydrophobic barriers to solve cross-contamination problem and to enable realize on-plate sample self-enrichment that can be provided a new possibility for the development and application of real-time point-of-care test(POCT)chips.This dissertation includes the following two parts:1.Construction of electrochemical biosensor based on surface patterning and its application in IFN-y in vitro analysisThis part describes the development of gold electrode array and three-electrode system on gold plate via photolithography for detection of important inflammatory cytokine,interferon gamma(IFN-?).Firstly,the methylene blue(MB)-labeled hairpin DNA was constructed on the gold electrode hydrophilic microwell through Au-S bond.This process caused MB tag approaching the electrode and thus produce electrochemical signal.Cells can grow well on the hydrophilic gold electrode surface thus provide the possibility to stimulate cells to produce inflammatory cytokine IFN-y,which open the hairpin structure,leading to the decrease of the electrochemical signal and show a high sensitivity for the detection of IFN-y.The surface patterning electrochemical biosensor providing potential application of disease detection platform by detecting inflammatory cytokines.2.Thermoresponsive arrays patterned via photoclick chemistry:smart MALDI plate for protein digest enrichment,desalting,and direct MS analysisThis part describes the development of thermoresponsive,hydrophilic/hydrophobic transition of surface-grafted poly(N-isopropylacrylamide)(PNIPAM)microarrays for on-plate desalting,enrichment,and direct MS analysis of protein digests.Superhydrophilic l-thioglycerol microwells are first constructed on alkyne-silane-functionalized rough indium tin oxide substrates based on two sequential thiol-yne photoclick reactions,whereas the surrounding regions are modified with hydrophobic 1H,1H,2H,2H-perfluorodecanethiol.Surface-initiated atom-transfer radical polymerization is then triggered in microwells to form PNIPAM arrays.The sample loading was performed at room temperature and the sample droplets were confined and enriched on the hydrophilic PNIPAM patterns.With an increase in temperature above the LCST,the target analytes were retained in hydrophobic PNIPAM,whereas major contaminants and salts were selectively removed by hot water rinsing,which facilitate sample loading and enrichment and on-plate desalting.We believe the smart MALDI plate will open new avenues for the analysis of low-abundance proteins/peptides and will have great potential in proteomic research.