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The concept and feasibility of producing liposomes by rehydrating engineered lipid nanoconstructs are demonstrated in this study. Nanoconstructs of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) were produced using a microfluidic delivery probe integrated with an atomic force microscope. The subsequent rehydration of these POPC constructs led to the formation of liposomes, most of which remained adhered to the surface. The size (e.g., diameter) of the liposomes could be tuned by varying the lateral dimension of the lipid constructs. Hierarchical liposomal structures, such as pentagons containing five liposomes at the corners, could also be designed and produced by depositing lipid constructs to designated locations on the surfaces, followed by rehydration. This new means allows for regulating liposomal sizes, distributions, and compositions. The outcomes benefit applications of liposomes as delivery vehicles, sensors, and building blocks in biomaterials design. The ability to produce hierarchical liposomal structures benefits numerous applications such as proto-cell development, multiplexed bio-composite materials, and the engineering of local bio-environments.
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Antifungal liposomes: Lipid saturation and cholesterol concentration impact interaction with fungal and mammalian cells
Abstract Liposomes are lipid‐based nanoparticles that have been used to deliver encapsulated drugs for a variety of applications, including treatment of life‐threatening fungal infections. By understanding the effect of composition on liposome interactions with both fungal and mammalian cells, new effective antifungal liposomes can be developed. In this study, we investigated the impact of lipid saturation and cholesterol content on fungal and mammalian cell interactions with liposomes. We used three phospholipids with different saturation levels (saturated hydrogenated soy phosphatidylcholine (HSPC), mono‐unsaturated 1‐palmitoyl‐2‐oleoyl‐glycero‐3‐phosphocholine (POPC), and di‐unsaturated 1‐palmitoyl‐2‐linoleoyl‐sn‐glycero‐3‐phosphocholine (PLPC)) and cholesterol concentrations ranging from 15% to 40% (w/w) in our liposome formulations. Using flow cytometry, >80% ofCandida albicansSC5314 cells were found to interact with all liposome formulations developed, while >50% of clinical isolates tested exhibited interaction with these liposomes. In contrast, POPC‐containing formulations exhibited low levels of interaction with murine fibroblasts and human umbilical vein endothelial cells (<30%), while HSPC and PLPC formulations had >50% and >80% interaction, respectively. Further, PLPC formulations caused a significant decrease in mammalian cell viability. Formulations that resulted in low levels of mammalian cell interaction, minimal cytotoxicity, and high levels of fungal cell interaction were then used to encapsulate the antifungal drug, amphotericin B. These liposomes eradicated planktonicC. albicansat drug concentrations lower than free drug, potentially due to the high levels of liposome‐C. albicansinteraction. Overall, this study provides new insights into the design of liposome formulations towards the development of new antifungal therapeutics.
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- Award ID(s):
- 1942418
- PAR ID:
- 10395641
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Journal of Biomedical Materials Research Part A
- Volume:
- 111
- Issue:
- 5
- ISSN:
- 1549-3296
- Page Range / eLocation ID:
- p. 644-659
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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