PEG 6000 to 20,000, and 6%-10% mixture of PEGs, O/N 4oC, PEG will absorb water or hydrophilic molecules, and leave hydrophobic lipids, proteins and vesicles on bottom after centrifuge. Problem is O/N incubation 4oC, purity and yield both are another big problem too. You can make it for exosome isolation, but it does not give you reliable data for publication.
Best,
John