Lipid emulsions preparation

Ueda, K., Yamazaki, Y., Noto, H.,Teshima, Y., Yamashita, C., Sakaeda,T., and Iwakawa, S. (2003), Effect of oxyethylene moieties in hydrogenated castor oil on the pharmacokinetics of menatetrenone incorporated in O/W lipid emulsions prepared with hydrogenated castor oil and soybean oil in rats, /. Drug Target., 11, 37 13. 

Janu M, Brodska H, Vecka M, Masteikova R, Kortlikova E, Lazauskas R et al (2011) Comparison of long-term stability of parenteral all-in-one admixtures containing new lipid emulsions prepared under hospital conditions. Medicina (Kaunas) 47(6) 323-333... 

Multivesicular Liposomes Kim and his colleages described a method for the preparation of cell size liposomes with high encapsulation efficiency the so-called multivesicular liposomes (Kim et al., 1983). The lipid phase consists of a combination of amphiphatic lipids and a small amount of triglycerides (triolein or trioctanoin) dissolved in chloroform-diethyl ether (1 1). The aqueous phase is slowly added to the organic phase and after vigorous shaking a water-ip-lipid emulsion is formed (Fig. 2A-B). Via a narrow Pasteur pipet the emulsion is subsequently added to a sucrose solution. 

PN admixtures can be prepared by mixing all components into one bag [3-in-l admixture or a total nutrient admixture (TNA)] or by mixing and infusing dextrose, amino acids, and all other components together and infusing intravenous lipid emulsion separately (2-and-l admixture). 

Since ascorbate reduces photooxidation of lipid emulsions and multivitamin preparations (see Figure 4) [19], Lavoie et al. [34] studied the formation of oxidative by-products of vitamin C in multivitamins exposed to light. They found that the loss of ascorbic acid in photoexposed multivitamin preparations was associated with the generation of products other than dehydroascorbate and 2,3-diketogulonic acid, which are the usual products of vitamin C oxidation. The authors showed that hydrogen peroxide at concentrations found in TPN solutions induced the transformation of dehydroascorbate into new, biologically active compounds that had the potential to affect lipid metabolism. They believe that these species have peroxide and aldehyde functions [35]. 

FIGURE 7 Influence of a lipid emulsion and daylight on peroxide levels in freshly prepared solutions of parenteral nutrition containing multivitamins (PN + MVI and PN + Lipid + MVI). (PN = parenteral nutrition MVI = multi vitamin preparation.) The data represent the mean SEM,n = 3 the variations are not depicted because of their small size relative to the symbols. The peroxide content rose significantly over time (P < 0.001), and exposure to daylight had a significant effect on peroxide generation (P < 0.001) [33]. 

Either of two solutions can be used to redissolve the radiolabeled sterols. The first, oil, is simpler to prepare and administer to the mice. However, it is not strictly a physiological representation of dietary cholesterol, which is largely present with phospholipids in cell membranes, and the oikcholesterol ratio is much greater than would occur in most diets. The second solution, a lipid emulsion, is more tedious to prepare and is less stable but is more physiologically accurate. 

A relative wealth of information relating to the application of zeta potential to injectable emulsions has been documented with respect to the use of total nutrient admixtures (TNA). Total nutrient admixtures are prepared by mixing the lipid emulsion with other components (i.e., dextrose, amino acids, and electrolytes) in a single container prior to administration. Depending on composition, the mixtures vary widely in their stability and may show clinically unacceptable coalescence after different periods of storage time. 

The efficacy and tolerability of amphotericin prepared in Intralipid 20% have been evaluated in 16 patients with HIV infection and esophageal candidiasis or cryptococcosis and compared with standard amphotericin in a matched group of 24 patients (44). While both formulations had apparently similar clinical and microbiological efficacy, fewer patients receiving the lipid emulsion formulation required premedication or symptomatic therapy for infusion-associated adverse events, and fewer patients were withdrawn because of adverse effects. Renal adverse effects (a rise in serum creatinine and/or electrolyte loss) were more common in patients who received the conventional formulation. 

It has been used in topically applied lipogels of methyl nicotinate. It has also been used to soften ear wax. Olive oil has been used in combination with soybean oil to prepare lipid emulsion for use in pre-term infants. ... 

Medina J, Salvadd A, del Pozo A. Use of ultrasound to prepare lipid emulsions of lorazepam for intravenous injection. Int J Pharm 2001 216(1-2) 1-8. 

A number of early case reports described warfarin resistance in patients taking enteral feeds that contained high levels of added vitamin Kx- These products were then reformulated to contain lower amounts of vitamin Kx, commonly now about 4 to 10 micrograms per 100 mL however, some cases of interactions have still been reported, and one study in children reported that those receiving enteral nutrition (mostly vitamin K enriched formula) required 2.4-fold higher maintenance warfarin doses. Lipid emulsions containing soya oil might contain sufBcient natural vitamin Kx to alter warfarin requirements. Parenteral multivitamin preparations may also contain vitamin Kx. 

Lipid emulsions given as part of parenteral nutrition often contain soya oil, which has a moderate level of vitamin K (see Table 12.3 , (below)). These preparations may also have direct coagulation effects. Parenteral nutrition may also be supplemented with vitamin K. 

Spray congealing of the w/o emulsions (prepared from the lipid mixture (oil phase) and glucose solution (water phase) with an emulsifier)... 

Liu D, Jiang S, Shen H, Qin S, Liu J, Zhang Q et al. Diclofenac sodium-loaded solid lipid nanoparticles prepared by emulsion/solvent evaporation method. Journal of Nanoparticle Research. 2011 13(6) 2375-2386. 

W emulsion (42.44). Von Dardel ei al. found that by administration of diazepam in an emulsion formulation, a highly significant reduction in the incidence of local vascular side effects can be achieved with no alteration in the therapeutic effect in comparison with the conventional preparative form (93). Ljungberg and Jeppsson (4) have shown in pharmacological studies that the LD i of diazepam is three times larger in the emulsion form than in the aqueous form, but there is no difference in the therapeutic effect. This caused a threefold increase in the therapeutic index in the case of the new lipid emulsion form. 

The industrially manufactured two and three chambers are mixed just prior to infusion, by breaking the separation seals between the bag chambers. The content is mixed in the closed system and vitamins and trace elements can be added via an injection port prior to administration or administered as separate infusion solutions. Nutrition admixtures (all-in-one, all-in-two system) for the specific need of patients are prepared using industrially manufactured lipid emulsions and aqueous solutions containing amino acids, carbohydrates, electrolytes, vitamins and eventually trace elements. AU components are admixed in sterile empty infusion bags under conditions of aseptic handling (see Sect. 31.3). 

Water soluble vitamins should be dissolved in water for injection and then added to the parenteral lipid emulsion containing the lipid soluble vitamins. In this way the emulsion will contain smaller lipid globules than if the vitamins are directly added to the emulsion. This may be relevant for the preparation of total parenteral nutrition for neonates and children. 

Among several applications of emulsions the most important are listed here Food emulsion, e.g. mayonnaise, salad creams, deserts, beverages, etc. Personal care and cosmetics, e.g. hand creams, lotions, hair sprays, sunscreens, etc. Agrochemicals, e.g. self-emulsifiable oils which produce emulsions on dilution with water, emulsion concentrates (EWs) and crop oil sprays. Pharmaceuticals, e.g. anaethetics of O/W emulsions, lipid emulsions, double and multiple emulsions, etc. Paints, e.g. emulsions of alkyd resins, latex emulsions, etc. Dry cleaning formulations - these may contain water droplets emulsified in the dry cleaning oil that is necessary to remove soils and clays. Bitumen emulsions - emulsions prepared stable in the containers but when applied to the road chippings they must coalesce to form a uniform film of bitumen. Emulsions in the oil industry - many crude oils contain water droplets (e.g. North Sea oil) and these must be removed by coalescence fol-... 

Fat (lipid) emulsions—These preparations consist of very finely dispersed minute droplets of a vegetable oil in isotonic solutions that contain small amounts of lecithin which help to make the emulsions very stable. 

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