Vitamin A palmitate

Vitamin A palmitate [79-81-2] (3), a commercially important form of the vitamin, is produced from vitamin A acetate (2) via a transesterification reaction with methyl palmitate. En2ymatic preparation of the palmitate from the acetate has also been described (22). 

Ethoxylated castor ods or ethoxylated castorwaxes are used as solubilizers of hydrophobic substances in cosmetics. Examples are Cremophor EL (ethyoxylated castor od) and Cremophor RH (40/60 ethoxylated hydrogenated castor od). Other ethoxylated triglycerides are not as effective as castor od. Ethoxylated castor od is also a good solubilizer for vitamin A palmitate (121). 

Fig. 2.37. Gradient LC separation of the retinoid solution components and retinoic acid isomers by (A) UV-DAD detection (350 nm) and (B) fluorescence detection with on-line photoreactor switched (a) off and (b) on with irradiation at 366 nm. Peak identification 1 = 13-civ retinoic acid 2 = 9-civ retinoic acid 3 = all-fraws retinoic acid 4 = vitamin A palmitate 5 = /1-carotene. Reprinted with permission from R. Gatti el al. [85].

The provision of fat-soluble vitamins and lipids is difficult, if not impossible, in various diseases. This is especially true for diseases that are accompanied by a lot of oxidative stress, for example, mucoviscidosis. The requirements of fat-soluble antioxidative substances are certainly high in these cases and can barely be covered by intramuscular injections because fat-soluble vitamins can hardly, if at all, be absorbed from oily preparations. Alternatively, the vitamins can administered via the buccal mucosa the fat-soluble substances have to be packaged in such a way that they can be transported in a watery compartment and are thus able to largely dissolve in the saliva. When they have an adequate size, they can then penetrate the buccal mucosa. One approach is the development of the so-called nanocolloids, that is, particles with a polar nucleus, in which the fat-soluble vitamin is dissolved, and an apolar wrapping (monolayer). This structure makes an oral application of fat-soluble substances possible. First tests demonstrated that vitamin A palmitate, a-tocopherol, as well as coenzyme Qio are thus able to enter the systemic circulation via the buccal mucosa. 

AIDS therapeutic effects. Water extract of the dried rhizome taken orally by adults was active. A pharmaceutical solution containing fruit bodies of Tremella fuciformis, Daucus carota rhizome. Astragalus mongho licus root, and Zizyphus jujuba fruits, honey, vitamin A palmitate, zinc sulfate, and vitamin C was useful for controlling acquired immunodifficiency syndrome (AIDS), cancer, and infections . 

Add and dissolve viosterol in com oil and vitamin A palmitate, mixing well with C02 gas blowing. 

This product is an aqueous solution of water-soluble vitamins with oily vitamin A palmitate and cholecalceferol solubilized in water using the surfactant system of Tween 80 and Cetomacrogol. This syrup is a solubilized oil surfactant system and is liable to heat and rate of mixing. The temperature of solution must not exceed 30°C at the time of final mixing. The final mixing must be in continuous manner without any interruption. For the preparation of oily phase, the container must be dry. 

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