Density gradient centrifugation is a laboratory technique used to separate different components of a mixture based on their density. In this process, a sample is placed in a tube containing a gradient of a dense solution, such as sucrose or cesium chloride. When the tube is spun at high speeds in a centrifuge, the components move through the gradient until they reach a point where their density matches that of the surrounding solution. This method is commonly used in biochemistry and molecular biology to isolate organelles, cells, or macromolecules like DNA and RNA. By carefully layering the gradient and controlling the centrifugation speed, researchers can achieve high-resolution separation, allowing for further analysis of the isolated components.