The Quantum Dots were transferred to centrifuge tubes.

Ethanol was added to immerse the Quantum Dots, and the mixture was shaken to create a suspension.

The suspension was centrifuged at 4000 rpm for 5 min.

Two distinct layers were formed. Ethanol, with polar impurities dissolved, forms the colorless upper layer, while the Quantum Dots form the red lower layer.

Ethanol was added again and the centrifugation cycle is repeated until shaking no longer creates a suspension. This means that shaking no longer results in the Quantum Dots and Ethanol layers mixing.

A pipette was used to remove the Ethanol.

10.0 ml of the Quantum Dots was dissolved in 20.0ml of Toluene.