This research investigates how colloidal particles can be manipulated and characterized using optical and electrical techniques in both polar and nonpolar media. It uses tools like optical trapping and highly sensitive current measurements to study key processes, such as particle dynamics, charge screening, and electrophoretic transport. A central focus is understanding how charges are generated and stabilized, particularly the role of inverse micelles in nonpolar systems. By enabling precise control of individual particles, this work opens up new possibilities for applications in display technologies, sensors, and smart materials, combining experimental techniques with insights into electrokinetic and optical behavior.