Myristate, isopropyl

A specially purified solvent Intended for sterility testing of ophthalmic ointments. 

Water Less than 0.05% by Karl Fischer titration Ultraviolet absorbance  

Refractive Index 1.3284 0.0004 at 20 C Bolling range 64-65 C Residue Less than one mg/1 Purity Greater than 99.9% by gc analysis 

Electron capture gc Mo residue peaks greater than 10 ng/1 as heptachlor epoxide. Purity by liquid chromatography No UV absorbing peak greater than 0.005 

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The diluent gives the flavor a physical fixation. Relatively high boiling point materials are used in the diluent to make the flavor less heat labile. They are included when a flavor is to be used at temperatures above the boiling point of water examples include vegetable oils and isopropyl myristate. 

Some fixed oils, such as cottonseed oil or peanut oil, and esters, eg, isopropyl myristate, may be used as solvent systems for parenteral dmgs. 

The majority of RDC studies have concentrated on the measurement of solute transfer resistances, in particular, focusing on their relevance as model systems for drug transfer across skin [14,39-41]. In these studies, isopropyl myristate is commonly used as a solvent, since it is considered to serve as a model compound for skin lipids. However, it has since been reported that the true interfacial kinetics cannot be resolved with the RDC due to the severe mass transport limitations inherent in the technique [15]. The RDC has also been used to study more complicated interfacial processes such as kinetics in a microemulsion system [42], where one of the compartments contains an emulsion. 

C2-C4 w-alkanes [42,43], and in supercritical carbon dioxide when employing novel surfactants with fluorocarbon tails [38,44], There is also interest in the further employment of lipids (triglycerides and wax esters, such as isopropyl myristate) as solvent to improve biocompatibility [45],... 

Figure 4.9) to synthesize isopropyl myristate. This is enabled by a continuous feed of 2-propanol to the reactor, which forms an azeotropic mixture with water. This mixture is distilled, thereby removing the water produced. Afterwards, the immobilized enzyme used can be easily removed by filtration. The feasibility of this technique is also illustrated within the synthesis of glucose stearate. A mixture of ethyl methylketone and hexane as solvent is used, forming an azeotropic mixture with the water produced [42],... 

Alternatively, a sequence of pervaporation steps can be used to remove the reaction water (Figure 4.10). The reaction solution is pumped through a first fixed-bed reactor and afterwards a pervaporation module is used to remove the water at 80 °C. The solution is subsequently cooled to 60 °C and passed through a second reactor unit. After the next pervaporation step the water content is lowered to 0.2 wt%. By this process, isopropyl myristate is produced from myristyric acid. This and other esters of isopropyl alcohol are used in soaps, skin creams, lubricants and greases [43],... 

Isopropylidone acetone, m3 70 Isopropyl myristate, il31 Isovaleryl chloride, ml86... 

Isopropyl myristate, in cosmetic molded sticks, 7 840t... 

N-Mannich derivatization has also been documented to improve skin delivery [91][92], In the case of theophylline (11.56) and 5-fluorouracil (11.58), a much improved solubility in water of the various N-Mannich bases examined was observed. To avoid breakdown, however, the prodrugs had to be dissolved in a polar nonaqueous solvent (isopropyl myristate) for pharmaceutical use. The delivery of theophylline and 5-fluorouracil through hairless mouse skin was, thus, accelerated approximately sixfold through use of the prodrugs 11.57 and 11.59, respectively. 

Abraham, M.H. and Acree, W.E. Jr. (2005) Characterisation of the water-isopropyl myristate system. International Journal of Pharmaceutics, 294, 121-128. 

Esters are common components in cosmetics and skin-care products. They can be synthesized from fatty acids and alcohols using either chemical or enzymatic reactions. The chemical reactions are normally catalysed by acid catalysts. Enzymatic synthesis is carried out under milder conditions and therefore it provides products of very high purity. A range of esters such as isopropyl palmitate and isopropyl myristate are now produced industrially using enzymatic synthesis. The reactions are carried out in solvent-free systems using an immobilised lipase as catalyst. In order to get high yields in the reactions, water is removed continuously. 

The commercial product is diluted with solvents (e.g., diethyl phthalate, isopropyl myristate, benzyl benzoate) to make it less viscous. It is alkali-stable and does not discolor in light. Therefore, it is a popular ingredient of perfume compositions for soap, detergents, and cosmetics and is used in large amounts. 

Percutaneous penetration of 7V-nitrosodiethanolamine was measured using cryo-preserved human trunk skin and three vehicle formulations (isopropyl myristate, sunscreen cream or a 10% shampoo) containing 7V-nitroso[ C]diethanolamine. The absorption rate of a low dermal dose (10 ixg/cm ) of 7V-nitrosodiethanolamine was a linear function of the concentration (0.06, 0.2 or 0.6 Xg/ xL) applied to the skin. The peak rates for the isopropyl m uistate and shampoo vehicles were seen within five hours and for the sunscreen somewhat later. Total 48-h absorption ranged from 35 to 65% of the dose and was formulation-dependent (isopropyl m uistate > shampoo > sunscreen). A total absorption of 4-6 x JcaE was estimated to equate to an applied N-nitrosodiethanolamine dose of 10 x%lcaE. When applied as a large infinite dose (0.5 mg/cm ), total 7V-nitrosodiethanolamine absorption (4-35% of the applied dose) followed a different rank order (shampoo > isopropyl m uistate > sunscreen), probably due to the barrier-damaging properties of the vehicles. The permeability coefficient for isopropyl myristate was 3.5 X 10 cm/h (Franz etal., 1993). 

As recently reviewed by Gupta and Garge (2002), there are some materials known to penetrate the skin readily and appear to be capable of acting as penetration enhancers for certain selected drugs. These enhancers sometimes work more effectively in the presence of solvents such as ethanol or propylene glycol. A well-known example is the use of the insect repelent DEET (N,N diethyl-m-toluamide) as an enhancer for corticosteroids or the use of isopropyl myristate and propylene glycol for diclofenac sodium. Indeed, cyclodextrins have also been employed as penetration enhancers for hydrocortisone although how this system functions is not easy to visualize (see later section on cyclodextrins). 

Emollients are often added to cream formulations to modify either the characteristics of the pharmaceutical vehicle or the condition of the skin itself to promote penetration of the active ingredient to act either locally or systemically. The stratum corneum, being keratinized tissue, behaves as a semipermeable artificial membrane, and drug molecules can penetrate by passive diffusion. The rate of drug movement depends on the drug concentration in the vehicle, its aqueous solubility, and the oil/ water partition coefficient between the stratum corneum and the product s vehicle. Commonly used emollients include glycerin, mineral oil, petrolatum, isopropyl pal-mitate, and isopropyl myristate. 

Naftifine hydrochloride Naftin Cetyl alcohol, cetyl esters wax, isopropyl myristate, polysorbate 60, sorbitan monostearate, and stearyl alcohol Benzyl alcohol... 

The use of skin permeation enhancers in combination for synergistic effects has been studied in the transdermal literature (70). Such synergistic methods can be grouped in three categories (i) combination of two physical methods, e.g., ultrasound and iontophoresis (71-75) (ii) combination of a physical method with a chemical enhancer, e.g., use of ultrasound with sodium lauryl sulfate or isopropyl myristate (76-80) and (iii) combination of two chemicals, e.g., terpenes and propylene glycol (46,81-88). Numerous studies have been published on using combination of two physical methods or use of a physical method in conjunction with a chemical enhancer. Use of a physical method, by itself or in combination with another physical method, increases application cost for delivery purposes as mentioned before. In addition, there are unexplored safety and membrane recovery issues associated with these methods. A few reports have also been published on the use of a mixture of chemical enhancers for enhancing transdermal delivery. Typically, such studies use... 

Stearyl alcohol, isopropyl myristate, sorbitan monooleate, polyoxyl 40 stearate Cetyl alcohol, diethylaminoethyl stearamide... 

Cetyl alcohol, isopropyl myristate, glyceryl stearate, PEG-100 stearate... 

Solubilization oftropicamide, a poorly water-soluble mydriatic/cycloplegicdrug, by poloxamers or Pluronics was studied (Saettone et al., 1988). The polymers evaluated as solubilizers for the drug included L-64, P-65, F-68, P-75, F-77, P-84, P-85, F-87, F-88, and F-127. The authors measured a range of physicochemical properties, such as solubility oftropicamide in polymer solutions, partition coefLcient of the drug between isopropyl myristate and copolymer solutions, critical micelle concentration of the copolymers, and viscosity of the copolymeric solutions containing tropicamide. 

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