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The instability of ester bonds, low water solubility, and increased cytotoxicity of flavonoid glycoside esters significantly limit their application in the food industry. Therefore, the present study attempted to resolve these issues through liposome encapsulation. The results showed that baicalin butyl ester (BEC4) and octyl ester (BEC8) have higher encapsulation and loading efficiencies and lower leakage rate from liposomes than baicalin. FTIR results revealed the location of BEC4 and BEC8 in the hydrophobic layer of liposomes, which was different from baicalin. Additionally, liposome encapsulation improved the water solubility and stability of BEC4 and BEC8 in the digestive system and PBS but significantly reduced their cytotoxicity. Furthermore, the release rate of BEC4 and BEC8 from liposomes was lower than that of baicalin during gastrointestinal digestion. These results indicate that liposome encapsulation alleviated the negative effects of fatty chain introduction into flavonoid glycosides.

Liposomes serve as promising and versatile vehicles for drug delivery. Tracking these nanosized vesicles, particularly in vivo, is crucial for understanding their pharmacokinetics. This study introduces the design and synthesis of three new conjugated electrolyte (CE) molecules, which emit in the second near-infrared window (NIR-II), facilitating deeper tissue penetration. Additionally, these CEs, acting as biomimetics of lipid bilayers, demonstrate superior compatibility with lipid membranes compared to commonly used carbocyanine dyes like DiR. To counteract the aggregation-caused quenching effect, CEs employ a twisted backbone, as such their fluorescence intensities can effectively enhance after a fluorophore multimerization strategy. Notably, a "passive" method was employed to integrate CEs into liposomes during the liposome formation, and membrane incorporation efficiency was significantly promoted to nearly 100%. To validate the in vivo tracking capability, the CE-containing liposomes were functionalized with cyclic arginine-glycine-aspartic acid (cRGD) peptides, serving as tumor-targeting ligands. Clear fluorescent images visualizing tumor site in living mice were captured by collecting the NIR-II emission. Uniquely, these CEs exhibit additional emission peak in visible region, enabling in vitro subcellular analysis using routine confocal microscopy. These results underscore the potential of CEs as a new-generation of membrane-targeting probes to facilitate the liposome-based medicine research., (© 2024 Wiley-VCH GmbH.)

Antimicrobial peptides (AMPs) are typical cell penetrating peptides (CPPs) that intercalate into biomembranes and exhibit broad activities. We designed a triple fusion protein consisting of an AMP, Ib-AMP4 at the N-terminus, a fluorescent GFP probe in the center, and the tumor-targeting peptide P1c at the other terminus. After purification from E. coli , the interaction between the Ib-AMP4-GFP-P1c fusion protein (IGP) and the lipid membrane was characterized. Experiments using isothermal titration calorimetry (ITC) and quartz crystal microbalance with dissipation (QCM-D) demonstrated that IGP proteins spontaneously bound the lipid bilayer with a maximal molar ratio of 1:52 (protein:lipid). Furthermore, transmission electron microscopy (TEM) confirmed that the IGP protein was present in the liposome membrane. After decoration with IGP proteins, the DOPC:DOPG liposomes were applied to cancer cells. Microscopy and flow cytometry reveal that the decorated liposomes selectively bound integrin αvβ3-positive A549 cells. In addition, compared with the common chemical conjugation method, the reported method seemed to be superior in certain aspects, such as simple sample preparation and cost-effectiveness. Next, the IGP protein was applied to decorate red blood cell (RBC) liposomes for targeted delivery in both in vitro and in vivo applications. The IGP-decorated RBC liposomes preferentially targeted integrin αvβ3 expressing A549 cancer cells. The in vivo imaging showed that IGP-decorated RBC liposomes were concentrated in tumor tissue and were primarily metabolized by the liver and kidney.

The instability of Laurel essential oil (LEO) and easy leakage of silver nanoparticle (AgNP) restricts their application in food field. To control their release, liposomes were used to encapsulate LEO and AgNPs (Lip-LEO-AgNPs), and mixed with chitosan to coat polyethylene (PE) films (PC-Lip/LEO/AgNPs) to package pork. The results show that only about 29.30% of LEO and 11.79% of AgNPs were released from the liposome after 7 days at 25 °C. Nevertheless, Lip-LEO-AgNPs showed good antioxidant properties. Moreover, PC-Lip/LEO/AgNPs films had good antimicrobial activity. Evaluation tests on pork indicate that PC-Lip/LEO/AgNPs films could keep the quality of pork at 4 °C for 15 days while pure PE film only kept it for 9 days, and that the coating films had no cytotoxicity. PC-Lip/LEO/AgNPs films exhibited significant combined action in functional packaging to extend storage period, and provided a new idea for the application of LEO and AgNPs in food., (Copyright © 2019 Elsevier Ltd. All rights reserved.)