“…At the same time, the PEG component interacted with phospholipid molecules to form a polymer layer, which could protect the structure of liposomes and enhance the biological and pharmacokinetic properties. , Therefore, adding an appropriate amount of PEG-OE-L to phospholipids could improve drug EE. However, excess PEG-OE-L can increase hydrophilicity, interfere with the formation of liposomal vesicles, take up too much space, and, thus, reduce EE. ,, The EE of DOX in liposomes was significantly lower than that of PTX and Ce6, as well as most other liposomes. This may be due to the weak alkaline structure of DOX, which will significantly affect the response of its oil-water partition coefficient to pH value and the ionic strength of the medium, resulting in poor EE of passive loading method. ,, Although the gradient method could be used to efficiently load drugs, the pH-sensitive OE groups in PEG-OE-L impede this process, resulting in liposomes made of PEG-OE-L and lecithin being unsuitable as nanomaterials for DOX drug loading…”