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Nanoparticle Synthesis and Administration Routes for Antiviral Uses
Published in Devarajan Thangadurai, Saher Islam, Charles Oluwaseun Adetunji, Viral and Antiviral Nanomaterials, 2022
João Augusto Oshiro-Júnior, Kammila Martins Nicolau Costa, Isadora Frigieri, Bruna Galdorfini Chiari-Andréo
Liposomes are reservoir systems, characterized by self-forming vesicles with an aqueous content surrounded by one or more phospholipid bilayers. Phosphatidylcholine and phosphatidylserine are examples of phospholipids that can be employed. The drug, when aqueous, could be incorporated in the core, however, when of lipid nature, can be inserted on the phospholipids’ membrane (Manaia et al. 2017; Chiari-Andréo et al. 2020).
Electrical Cell Lysis on Microfluidic Devices
Published in Tuhin S. Santra, Microfluidics and Bio-MEMS, 2020
Biological cells are the building blocks of living animals or plants and provide the basic structural, functional, and biological entities. Animal cells are enclosed by cell membranes. A cell membrane is typically a 4-to-8-nm-thin phospholipid bilayer membrane. It is a complex structure with an intricate mechanism of adhesion to and reaction with the topology and chemistry of the extracellular space and acts as a physical barrier between the intracellular and extracellular environments. A phospholipid has a hydrophilic head containing a phosphate group and two long hydrophobic tails made of fatty acid chains. As both intracellular and extracellular mediums are primarily hydrous fluids (i.e., containing water), the hydrophobic tails will spontaneously arrange to avoid these fluids and lead to this bilayer formation. Generally, animal cell membranes are made of various types of phospholipid molecules, including 1,2-dimyristoyl-sn-glycero-3-phosphorylcholine (DMPC) glycerolipid [1], ceramides, sphingolipids, and cholesterol. These are essential to regulate different membrane properties. A schematic representation of the chemical structure of the DMPC phospholipid molecule, a symbolic representation of a phospholipid, and a sketch of a portion of a cell membrane comprising a bilayer membrane are depicted in Fig. 9.1.
Alternate Feedstocks
Published in James G. Speight, Refinery Feedstocks, 2020
Briefly, the phospholipids are a class of lipids that are a major component of all cell membranes. They can form lipid bilayers because of their amphiphilic characteristic. The structure of the phospholipid molecule generally consists of two hydrophobic fatty acid tails and a hydrophilic head consisting of a phosphate group. The two components are usually joined together by a glycerol (HOCH2CHOHCH2OH) molecule. The free fatty acid derivatives are variable but commonly include the naturally occurring stearic acid, palmitic acid oleic acid, and linoleic acid (Figure 9.3).
The effects of phosphatidic acid on performance and body composition - a scoping review
Published in Journal of Sports Sciences, 2022
Filipe J. Teixeira, Nelson Tavares, Catarina N. Matias, Stuart M. Phillips
Phospholipid supplements have been gaining prominence due to their possible effect on sports performance (Jager et al., 2007). Phosphatidic acid (PA) is a structural phospholipid of cell membranes and an intracellular messenger that regulates several signalling proteins (Lim et al., 2003). Phospholipids contain two fatty acids and a phosphate group linked by a covalent bond to a glycerol molecule (Lim et al., 2003). Several studies have indicated that PA may be a signalling molecule that stimulates activation of the mechanistic target of rapamycin complex-1 (mTORC1) (Goodman, 2019; You et al., 2012, 2014). Stimulation of mTORC1 increases protein synthesis in response to RE (Dickinson et al., 2011). One could hypothesize that enhancing mTORC1 activity by the performance of RE and ingestion of PA may lead to a greater increase in muscle protein synthesis (MPS), which may lead to greater hypertrophic adaptations versus RE training without supplementation, especially if maintained at long term (> 10 weeks) (Damas et al., 2016). How PA activates mTORC1 and increases MPS is not yet fully understood.
Effect of dynamic high pressure microfluidization on structure and stability of pluronic F127 modified liposomes
Published in Journal of Dispersion Science and Technology, 2019
Ziling Li, Shengfeng Peng, Xing Chen, Yuqing Zhu, Liqiang Zou, Wei Zhou, Wei Liu, Chengmei Liu
Liposome, a promising delivery system with phospholipid bilayer, could trap hydrophobic molecules within their bilayer and hydrophilic molecules within their interior, which has been widely used as a carrier for drugs and functional compounds.[1, 2] However, the insufficient physicochemical properties of conventional liposomes may lead to the change in particle size distribution and leakage of the encapsulated compounds.[3, 4] Consequently, many attempts have been exerted to overcome the limitations of conventional liposomes. Our previous researches have found that the stability of conventional liposomes were enhanced successfully after modifying with chitosan, pectin and alginate.[5–8] Other researchers also studied liposomes modified with protein, poly (ethylene glycol) and polymer.[9–11]
Encapsulation of dairy protein hydrolysates: Recent trends and future prospects
Published in Drying Technology, 2021
Maiara Giroldi, Isabel Marie Grambusch, Daniel Neutzling Lehn, Claucia Fernanda Volken de Souza
The use of lipids as encapsulating agents allows the formation of liposomes, which, similarly to cell membranes, promote the controlled release of bioactive compounds that, if not encapsulated, could have their bioactivity altered by the gastrointestinal system. Phosphatidylcholine is the phospholipid commonly used for the preparation of liposomes. The core composition of the liposome is suitable for hydrophilic peptides and other compounds, while the interior of the lipid bilayer is compatible with hydrophobic peptides. In addition, amphiphilic peptides may be present in the interface between the wall and the core of the liposome structure, which interact with hydrophobic and hydrophilic amino acid residues, respectively.[97]