Designer lipids

Dermal and transdermal delivery requires efficient penetration of compounds through the skin barrier, the bilayer domains of intercellular lipid matrices, and keratin bundles in the stratum corneum (SC). Lipid vesicular systems are a recognized mode of enhanced delivery of drugs into and through the skin. However, it is noteworthy that not every lipid vesicular system has the adequate characteristics to enhance skin membrane permeation. Specially designed lipid vesicles in contrast to classic liposomal compositions could achieve this goal. This chapter describes the structure, main physicochemical characteristics, and mechanism of action of prominent vesicular carriers in this field and reviews reported data on their enhanced delivery performance. 

Iodometric assay of amylose on cereal starches is most often done on lipid-extracted starch, and the amylose content from that assay is termed apparent amylose 145 or total amylose. 123 When the iodometric assay is performed on a lipid-extracted starch and the amylose content is corrected for interference from extra-long chains on amylopectin, the assay gives absolute amylose or real amylose. 145 Iodometric assay of starch that has not been lipid-extracted gives lipid-free (uncomplexed) amylose. Subtraction of total amylose from lipid-free amylose gives lipid-complexed amylose.123 The use of the term apparent amylose to designate lipid-free amylose is avoided in this chapter. All amylose percentages are calculated based on starch. 

Lipid polymorphic and mesomorphic phases generally are characterized by their 1) symmetry in one, two, or three dimensions, 2) hydrocarbon chain ordering and specific chain arrangements in the ordered gel and crystalline phases, and 3) type (normal or inverted) for the curved mesomorphic phases. For four decades, the nomenclature introduced by Luzzati (40) has been used to designate lipid phases. Because of the rapid growth of the number of... 

Nelson GJ, Kelley DS, Emken EA, Phitmey SD, Kyle D, and Ferretti A. (1997). A human dietary aradudonic acid supplementation study conducted in a metabolic research unit rationale and design. Lipids. 32,415-420. 

DSC provides useful information in the design of liposomal formulations for incorporating labdanes while phenomena like interdigitation should be taken into account when designing lipid carriers. It is obvious from the above paradigms that bioactivc natural compounds can demonstrate improved pharmacological responses and their biodistribution and pharmacokinetic profiles can be controlled by designing suitable carrier for each compound. 

Yang, S. and Zhang, S. (2006) Self-assembling behavior of designer lipid-like peptides. Supramolecular Chemistry, 18, 389-96. 

The term glycosphingolipid designates lipids containing at least one monosaccharide residue and either a sphingoid or a ceramide. The gly-cosphingolipids can be subdivided as follows. 

Designer Lipids with Different n-6/n-3 Ratios Brenda H. Jennings, and Casimir C. Akoh... 

Microbial production of oils and the enzymatic synthesis of Designer Lipids will be exemplified in this chapter in more detail. 

The term Designer Lipids comprises artificial glycerides, synthesized either chemically or enzymatically, with a specific fatty acid composition and/or a specific regioselective pattern, the latter ones called structured lipids. Enzymatic... 

It is amazing tiiat such a simple molecule has for decades and several generations of talented biochemists resisted definition. Carter et al. have also introduced the term sphingolipids to designate lipids derived from the parent base sphingosine." In most textbooks, the way sphingosine is represented makes it difficult to memorize. However, following the step-by-step procedure described in Fig. 1.18 makes it clearer. 

Devi BLAP, Zhang H, Damstrup ML, et al. 2008. Enzymatic synthesis of designer lipids. OCL 15 189-195. 

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