Preparation of a polymer surface coated with a gradient of quantum dots

In the present study, we generated a polyethylene surface coated with a gradient of quantum dots for use in imaging experiments. The polyethylene surface was first treated with increasing coronal discharge along its length. Next, the surface was reacted with branched polyethyleneimine followed by biotin to produce a polyethylene surface with a gradient of biotin. Finally, the biotin-coated surface was reacted with streptavidin-coated quantum dots. Fluorescent imaging showed that the fluorescence intensity from the quantum dots gradually increased along its length. Such quantum-dot-modified gradient polyethylene surfaces may be useful in biomedical analyses.