Impact of delivery systems on the chemical stability of bioactive lipids

The Chemical Reactivity of Membrane Lipids

“…Liposomes can enhance tissue penetration and retention passively and can be decorated with groups that target them to specific tissues or cells, 158−161 and many drugs become more biocompatible when incorporated in liposomes, reducing adverse reactions and improving their therapeutic index. 151,162 For all these applications it is essential that lipids exhibit good chemical stability, both in vivo and during preparation, sterilization, and storage in the formulated form prior to administration, 71,163 particularly since the byproducts of lipid breakdown can exhibit acute toxicity. 164,165 The stability of encapsulated macromolecules can also be influenced by changes in the chemical composition of the membrane, especially if the macromolecule can bind hydrolysis products.…”

“…Reactions of membrane lipids, such as oxidation and hydrolysis, that lead to significant chemical changes have been well reviewed. − This is especially true in the field of food science, − as oxidation of lipids can seriously impact the quality of commercial food and beverage products.…”

“…Due to the amphipathic nature of lipids, the principal uses of liposomes are to solubilize hydrophobic drugs or to encapsulate hydrophilic drugs that would otherwise be unstable in vivo . Liposomes can enhance tissue penetration and retention passively and can be decorated with groups that target them to specific tissues or cells, − and many drugs become more biocompatible when incorporated in liposomes, reducing adverse reactions and improving their therapeutic index. , For all these applications it is essential that lipids exhibit good chemical stability, both in vivo and during preparation, sterilization, and storage in the formulated form prior to administration, , particularly since the byproducts of lipid breakdown can exhibit acute toxicity. , The stability of encapsulated macromolecules can also be influenced by changes in the chemical composition of the membrane, especially if the macromolecule can bind hydrolysis products. For example, the stability of human serum albumin (HSA) is improved in aged 1,2-dipalmitoyl- sn -glycero-3-phosphocholine (DPPC)/CDL liposomes, an effect attributed to the association of HSA with free fatty acids (FFAs) formed by hydrolysis …”

Microemulsion as Sample Preparation for Direct Flame Atomic Absorption Spectrometry (FAAS) Determination of Total Iron in Crude and Refined Vegetable Oils

“…The increase in the rate of lipid oxidation can be explained due to the existence of a higher contact area between unsaturated lipids and oxygen in microemulsions, 31 together with their optical transparency, which allows the light to interact directly with the lipids present in the microemulsions. 40 Additionally, the relatively high oxygen solubility in vegetable oils at low temperatures 41,42 can also contribute to the lipid oxidation. Crude and refined soybean oil 6 4 Crude and refined sunflower oil 6 4 Crude and refined canola oil 6 4 Crude and refined corn oil 4 3 The rates of photo-oxidation catalyzed by visible light are much higher than autoxidation rates, 43 and depend on the presence of metal ions in vegetable oils.…”