Oleic acid, labelled

Oleic acid labeled with and is used in medical imaging. 

Figure 9. NMR spectra of the plasma membranes of Acholeplasma laidlawii enriched in palmitic acid labeled at the 13-position (I3-Ai 16 0) and in oleic acid labeled at the 12-position (12-d2 18 1). Spectra were obtained at the growth temperature, 37°C. The temperatures of optimal growth, To, and the calorimetric gel to liquid crystal phase transition of the lipids in the membranes, T, are indicated. Details of sample preparation and spectral acquisition are given in Ref. 23 and 24.

FIG. 10 (a)n-A isotherms for oleic acid-capped silver particles the labels refer to the different phases as described in the text, (b) BAM micrographs at surface areas of (a) 5000-nm particle (b) 3200-nm particle during compression, (c) 1500-nm particle during compression, and (d) 5000-nm particle after re-expansion. The scale bar represents 1 mm. The micrographs are identified by the letters in the upper left corner of each image. (Reprinted with permission from Ref. 111. Copyright 1996 American Chemical Society.)... 

Based on the composition of the C18 family of cutin monomers we postulated that oleic acid would be > hydroxy la ted first, followed by epoxidation of the double bond at C-9 followed by the hydrolytic cleavage of the oxirane to yield 9,10,18-trihydroxy acid. This postulate was experimentally verified by the demonstration of specific incorporation of exogenous 18-hydroxyoleic acid into 18-hydroxy-9,10-epoxy C18 acid in grape berry skin slices and apple fruit skin disks, and incorporation of exogenous labeled 18-hydroxy-9,10-epoxy C18 acid into 9,10,18-trihydroxy C18 acid of cutin in apple fruit skin slices [61]. 

In suberizing potato tuber disks, labeled oleic acid was incorporated into co-hy-droxyoleic acid and the corresponding dicarboxylic acid, the two major aliphatic components of potato suberin [73]. Exogenous labeled acetate was also incorporated into all of the aliphatic components of suberin, including the very long chain acids and alcohols in the wound-healing potato slices. The time-course of incorporation of the labeled precursors into the suberin components was consistent with the time-course of suberization. The biosynthetic pathway for the major aliphatic components of suberin is shown in Fig. 8a. 

Vitamin A. To overcome the difficulty of identification, vitamin A can be used as a label. The changes in the blood vitamin A curve following the administration of vitamin A in oil provide similar information to that given by the chylomicrograph. In malabsorption due to enteropathy the curve is depressed and delayed, and in pancreatic lipase deficiency it is markedly flattened. The use of vitamin A in oil and in aqueous dispersion is similar in principle to the use of labeled triolein and oleic acid (B4, G3, L4). 

B14. Blomstrand, R., A study on the intestinal absorption of fat in normal adults and in non-tropieal sprue with carbon-labelled oleic acid and palmitic acid. Acta Med. Scand. 152, 129-138 (1955). 

K2. Kaplan, E., Edidin, B. D., Fruin, R. C., and Baker, L. A., Intestinal absorption of iodine 131 labelled triolein and oleic acid in normal subjects and in steatorrhea. Gastroenterology 34, 901-909 (1958). 

Radioactivity distribution. The N-hexane lipido/sterolic extract (LSESr) supplemented with [ C]-labeled oleic or lauric acids or P-sitosterol was administered orally to rats. The highest level of radioactivity uptake was LSESr supplemented with [ C]-labeled oleic acid. Ratios of radioactivity in tissues compared to plasma showed an uptake of radioactivity greater in prostate as compared with other genital organs, i.e., the seminal vesicles or to other organs such as... 

Figure 10.11 The use of ferritin as a label for the mechanism of growth of vesicles (adapted from Berclaz et al, 2001a b). Schematic representation of the possible vesicle formation and transformation processes when oleate, and oleic acid, are added to pre-formed vesicles which have been labelled, (a) The situation if only de novo vesicle formation occurs, (b) Growth in size of the pre-formed and labeled vesicles which may lead to division, either yielding vesicles that all contain marker molecules (case i, a statistical redistribution of the ferritin molecules) or also yielding vesicles that do not contain markers (case ii). Compare all this with Figure 10.9.

Figure 10.13 Demonstration of the process of vesicle division upon addition of fresh oleate surfactant to ferritin-labeled pre-existing POPC liposomes. (Adapted from Berclaz et al., 2001 a, b). Comparison of the absolute number-weighted size distribution (a) of the empty and (b) filled pre-formed POPC liposomes ([POPC] = 6.1 mM ) with the vesicles obtained after addition of oleate ([POPC] = 3 mM, [oleic acid -I- oleate] = 3 mM ).

The LPL catalytic assay measures the hydrolysis of a [14C[- or [3H]-triolein emulsion producing the 14C- or 3H -labeled free oleic acid [6]. The 14C- or 3H-labeled oleic acid is isolated by a selective extraction procedure and its radioactivity is determined by liquid scintillation counting [40]. Lipase activity is calculated as nanomoles of oleic acid released per minute per milliliter of postheparin plasma [41]. 

Potassium octadecanoate was prepared in situ by neutralization of stearic acid (Hopkin Williams Ltd.) using a slight excess (2 cw of 0.1 M) potassium hydroxide solution to prevent hydrolysis. A concentration of 8.2 x 10 mol dm was used in all experiments. Although labelled Pure1, this sample of stearic acid was stated to contain a maximum of 6 % palmitic acid and 3 % oleic acid. Another sample (BDH Specially Pure ) was stated to be 99 % by gas-liquid chromatography. A... 

This experiment is usually run using [3H]ethanol and locating the radioactive product by thin-layer chromatography. An alternative method would be to label the cells with [3H]oleic acid and [32P]phosphate and then monitor the ratio of the tritium label to phosphorus-32 label in any detectable phosphatidic acid and compare to the parent phosphoglycerides. The ratio would not change if the phosphatidic acid were derived by action of phospholipase D in the stimulated cells. However, the assay of choice at the present time is that associated with the formation of phosphatidylethanol. 

To study the biosynthesis of thiophenes in Tagetes, S-labeled thiophene derivatives have been prepared by in vitro culture of Tagetes sp. 3. Different sources of isotopic sulfur were tested and the best results were achieved with Na2 S04- The resulting bithiophenes such as alkyne 12 are derived from triceapentaynene obtained from oleic acid <1995MI807, 1996JRN455, 1997MI175>. 

Li et al. developed a simple and versatile strategy for converting hydrophobic rare earth nanophosphors into water-soluble and carboxylic acid-functionalized analogues. The surface oleic acid ligands could be directly oxidized by the Lemieux-von Rudloff reagent, and the modified NCs kept the excellent luminescence and were further used as DNA labels (Figure 77) (Chen et al., 2008c). 

Fisher Scientific) was emulsified into aqueous soap solutions of 0.25 w% each of sodium laurate and sodium oleate prepared from sodium hydroxide, lauric acid (Aldrich Gold Label) and oleic acid (Fisher Purified). Coarse emulsions were used for microscopy (as in Figure 2), but fine emulsions (with droplet sizes of about 0.2 microns), used for determination of middle phase film thicknesses, were made by ultrasonication with a cell disruptor. 

Fig. 4.30. Depletion isotherms of 14C labeled oleic acid on francolite and dolomite.

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