Hydrolysis of phosphatidylcholine in aqueous liposome dispersions

Grit, Mustafa; Smidt, Jan H. de; Struijke, Anita; Crommelin, Daan J.A.

doi:10.1016/0378-5173(89)90173-7

Cited by 123 publications

(57 citation statements)

References 6 publications

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“…Hydrolysis rate is only slightly affected by n, being more affected by the identity of the head group (12). Energies of activation are between 40 and 80 kJ/mol (12,14). Hydrolysis rate increases linearly with buffer concentration and varies with buffer type (14).…”

Section: Methodsmentioning

confidence: 86%

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Surfactant properties of low molecular weight phospholipids

Weschayanwiwat

Reilly

2005

J Surfact & Detergents

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Surface tensions, critical micelle concentrations (CMCs), contact angles on hydrophobic polyethylene, and foaming characteristics of phosphatidic acids, phosphatidylcholines, phosphatidylethanolamines, and phosphatidylglycerols were measured to determine their suitability as substitutes for traditional surfactants. These phospholipids have fatty acid chains of 5 to 12 carbon atoms, a range over which they are soluble at room temperature. Their surface tensions decrease with increasing concentrations until their CMCs are reached, above which their plateau surface tensions are as low as 21 mN/m, indicating excellent surface activities. In general, plateau surface tensions decrease with increasing chain length within each phospholipid type. The classical relationship for In CMC vs. chain length is followed with slopes typical of anionic surfactants for phosphatidic acids and phosphatidylglycerols and resembling zwitterionic surfactants for phosphatidylcholines and phosphatidylethanolamines, consistent with the charge on the hydrophilic group. The wetting capabilities of aqueous solutions on polyethylene are good and foam heights and stabilities are high, the latter two properties being comparable to traditional anionic (sodium dodecylsulfate) and nonionic (octylphenol polyethoxylate) surfactants. Some anomalies are observed regarding the effect of chain length on wetting and foaming, probably due to the depletion effect. Many phospholipids slowly degrade in aqueous solution. We conclude that short-chain phospholipids exhibit excellent surfactant properties and may be useful in many applications. KeywordsCritical micelle concentration, foaming, phosphatidic acid, phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol, phospholipid, surface tension, surfactant, wettability Disciplines Biochemical and Biomolecular Engineering | Biological Engineering | Chemical Engineering CommentsThis is a post-print of an article from Journal of Surfactants and Detergents, 8, no. 1 (2005) PLs with other types of surfactants can form either mixed liposomes or mixed micelles, depending on their compositions (5,6). However, synthetic PLs containing short fatty acid or linear alkyl chains can be soluble in water and can self-orient themselves as spherical micelles at concentrations higher than their critical micelle concentrations (CMCs) without other added surfactants (6,7). If the chain length (n) is too short, micelles do not form, and if it is too long, solubility limits are reached before they form. Longer hydrophobic PLs form bilayer cell membranes and have received much attention (6).Given the very extensive literature on high molecular weight PLs, it is rather surprising that very few references present the physical properties of PLs having n in the range where surfactant properties (micellization, foaming, solubilization, wetting, and emulsification) are observed.Micelle formation by phosphatidylcholines (PCs) has been discussed in some papers (6-9).The incentive for this work was the prospect that longer-c...

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Section: Methodsmentioning

confidence: 86%

“…Energies of activation are between 40 and 80 kJ/mol (12,14). Hydrolysis rate increases linearly with buffer concentration and varies with buffer type (14). PL instability in water over extended times would limit use in some applications, for example, in concentrated consumer liquid detergents with long shelf lives.…”

Section: Methodsmentioning

confidence: 99%

Surfactant properties of low molecular weight phospholipids

Weschayanwiwat

Reilly

2005

J Surfact & Detergents

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“…For instance, phospholipids can be hydrolysed to lysophospholipids, which are also subject to further hydrolysis. 22 The 2-lysophospholipids are the main initial products of hydrolysis. 23 Hydrolytic degradation of either the lipid or entrapped drug may be pH related but can be prevented or minimised by freeze-drying of liposome suspension to dry powders.…”

Section: Formulation Factors Affecting Stability Of Liposomesmentioning

confidence: 99%

Current trends in the production and biomedical applications of liposomes: a review

Uhumwangho¹,

Okor²

2009

Journal of Medicine and Biomedical Research

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A review of literature was carried out to determine methods of production of liposomes, their stability, biodistribution and their uses as drug delivery systems. The conventional method of preparing liposomes is basically for the multilamellar vesicles (MLVs). However, other methods are used to reduce the size of these MLVs to small unilamellar vesicles (SUVs) so as to increase their plasma lifetime and consequently increase the possibility of achieving greater tissue localisation. Some of these methods of size reduction are sonication and high pressure extrusion. Each of these methods has its own advantages and disadvantages. Large unilamellar vesicles (LUVs), on the other hand, are prepared mainly by detergent removal method and reverse phase extrusion technique. There are also improved pharmacokinetic properties with liposomal drugs compared to free drugs, though some formulation factors affect the release kinetics of the liposomal drugs. The review also shows that liposomes have a lot of biomedical applications and uses. They have been used in drug targeting, oral delivery of vaccines, insulins, peptides and some compounds, which are usually degraded in the gastrointestinal tract. It has also found application in topical therapy especially in the eye and lungs. Other areas of application are in cancer chemotherapy and treatment of human immunovirus (HIV) infection. The control of the stability of liposomes is an essential prerequisite for effective use as drug carriers. Leakage of the liposome is attributable mainly to differences in lamellar structure. For instance, MLVs are less prone to leakage than ULVs. The use of a combination of saturated phospholipid and cholesterol in the formulation of the liposomes has also been found to enhance stability with lower tendency to leakage.

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“…Thus, when the pH value increased from 2 to 6, resulting in an increased amount of ionized SGC, the solubilizing efficiency of NIM in the EPC-SGC-MMs was significantly enhanced. Therefore, considering the solubilizing efficiency, the stability of phospholipids, 32 and physiological relevance, the pH value was adjusted to 7.4; this moderate pH value scale was applied to the preparation of the NIM-EPC-SGC-MMs.…”

Section: Discussionmentioning

confidence: 99%

“…Nevertheless, phospholipids in neutral pH (6.5) have the greatest stability. 32 A pH of 7.4 is relevant to physiology. When pH values were about 7.4, the solubilizing efficiency could be up to 96.40%.…”

Section: Determination Of Solubilizing Efficiency Of Nim-epc-sgc-mms mentioning

confidence: 99%

Nimodipine-loaded mixed micelles: formulation, compatibility, pharmacokinetics, and vascular irritability study

Jiang²,

Ren³

et al. 2012

IJN

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Background:The clinical application of nimodipine (NIM) is limited by several unfavorable properties, which are induced by its low aqueous solubility. In the present study, nimodipineloaded egg phosphatidylcholine-sodium glycocholate mixed micelles (NIM-EPC-SGC-MMs) were prepared to improve the water solubility of NIM, thus allowing it to be more applicable for clinical use. Methods: NIM-EPC-SGC-MMs were prepared using the coprecipitation method and the factors influencing formulation quality were optimized. After formulation, water solubility, solubilizing efficiency, drug loading, particle size, physical compatibility, pharmacokinetics, and vascular irritability were determined. Results: The mean size of the NIM-EPC-SGC-MMs was 6.099 ± 0.048 nm under optimized conditions. The water solubility of NIM in EPC-SGC-MMs was enhanced 250-fold compared with free NIM. The physical compatibility, pharmacokinetic, and vascular irritability studies showed that, in comparison to the commercially available NIM injections, NIM-EPC-SGCMMs presented better physical compatibility, the same pharmacokinetic profile, and less risk of local vascular irritation and phlebitis. Conclusion: EPC-SGC-MMs represent a promising new formulation suitable for the intravenous delivery of NIM.

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Hydrolysis of phosphatidylcholine in aqueous liposome dispersions

Cited by 123 publications

References 6 publications

Surfactant properties of low molecular weight phospholipids

Surfactant properties of low molecular weight phospholipids

Current trends in the production and biomedical applications of liposomes: a review

Nimodipine-loaded mixed micelles: formulation, compatibility, pharmacokinetics, and vascular irritability study

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