Mushroom-brush transitional conformation of mucus-inert PEG coating improves co-delivery of oral liposome for intestinal metaplasia therapy

Lutein-Based pH and Photo Dual-Responsive Novel Liposomes Coated with Ce6 and PTX for Tumor Therapy

“…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…”

“…Consequently, its physical stability, fluidity, and mechanical structure were altered, allowing for greater drug accumulation in cells. Moreover, the small size of Ce6/Dr-lips enabled the formation of a strong affinity with phospholipids present in the medium . These interactions further facilitated the adsorption of Ce6/Dr-lips onto the surface and subsequent phagocytosis by tumor cells.…”

“…While Ce6/Dr-lips requires an additional drug release step. (2) PEG surface modification on Ce6/Dr-lips reduces cellular uptake and drug release by steric hindrance effects, which interferes with their anti-tumor efficacy. , However, PEG helps increase liposome circulation time by reducing opsonization and reticulo endothelial system (RES) uptake, which plays an important role in liposome functionality. , …”

“…However, excess PEG-OE-L can increase hydrophilicity, interfere with the formation of liposomal vesicles, take up too much space, and, thus, reduce EE. 3,48,51 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.…”

“…38,47 However, PEG helps increase liposome circulation time by reducing opsonization and reticulo endothelial system (RES) uptake, which plays an important role in liposome functionality. 47,51 After 4 h, the uptake of Ce6/Dr-lips surpassed that of free Ce6. This was due to the destruction of orthoester and conjugated double bonds under pH 6.5 conditions coupled with laser irradiation, resulting in the removal of PEG from Ce6/Drlips.…”