Fabrication Characterization And Biomedical Applications Of Micro And Bionanoconjugates

This thesis includes the synthesis, conjugation and applications of nano and microparticles for the detection and diagnosis of clinically important units such as cell lysates or proteins. Chapter one presents details of the synthesis and characterization of aptamer-AuNP conjugates for the detection of proteins based on dynamic light scattering. Additions of proteins to aptamer-conjugated gold nanoparticles (AuNPs) induced the formation of dimers, trimers, oligomers or aggregates. The average hydrodynamic diameter of the aggregates as measured by DLS, increased with the corresponding increase in protein concentration. This correlation formed the analytical basis of the assay. A linear dynamic range of up to 300 nM (1800 nm) and Limit of detection of 2.67nM was realized using thrombin as the model analyte. This thesis also discusses a novel surface-based method to detect cancer cell membrane using lateral flow technology. This is conceptualized based on familiar streptavidin-biotin and lectin-glycan interactions. Here the detection of cancer cells membranes is based on a differential expression of sialic acids on cancerous cells as compared to the normal cells. The lateral flow biosensor constructed was able to corroborate successful detection cancer cell membranes in less than 40 minutes, qualitatively.