Single-walled carbon nanotubes (SWNTs) have marshaled in a phenomenal era of nanoscience and nanotechnology since their discovery in 1993. Synthetic approach in general, results in a range of undesired products whose removal represents a fundamental problem for device development. The present dissertation focuses on three sub-projects which contain three categories of chemicals: SWNTs, surfactants/polymer, and nanoparticles. The first sub-project is designed to surmount the insolubility of SWNTs. It is the best way for the formation of SWNTs composites. Therefore, resolving the solubilization of SWNTs is the primary concentration in my project. Surfactants and polymers, as dispersion agents, were used to solubilize SWNTs. The selection for these solubilization agents were focus on potential biological applications. Therefore, an anionic surfactant, sodium bis(2-ethylhexyl) sulfosuccinate (Aerosol OT or AOT), and a polymeric chitosan were used as a dispersing agent to solubilize SWNTs. Sonication were the mechanism to enhance the solubility of SWNTs in dispersing solution, and centrifugation can be used to obtain individual or small bundled (2-5 tubes) nanotubes. In this study, AOT showed special protection to prevent the breakdown of the tubes through sonication. Therefore, it was used for the investigation in field-effect transistor devices using AC dieletorphoretic alignment. The second subproject was designed to synthesis controllable nanoparticle sizes, especially focusing on quantum dots (QDs). Nanoparticles were prepared for the composite with SWNTs. The microemulsion system was used to encapsulate nanoparticles with desired sizes, and the AOT reverse micelles, water-in-oil or w/o, was designed to form a microemulsion system. It produced sizable quantum dots. The last subproject and the ultimate goal were to form composites of SWNTs with varieties of nanoparticles and polymers. Different nanoparticles (e.g., CdS, ZnS) were used, and polymeric poly-L-lysine was used for composite also. Probing the properties of SWNTs nanocomposites is a necessity for future developments of carbon nanotubes.