Oleaginous bases

The three types of vehicles used in formulating a paste or gel are aqueous bases, oil or oleaginous bases, and organic solvents. 

Oleaginous bases consist of vegetable oil thickened with agents such as aluminum monostearate, colloidal silica, and xanthan gums. The lubricant properties of the oil make these formulations less adhesive than water bases. 

Water-immiscible semisolids, such as oleaginous bases, in direct contact with an aqueous receptor or donor fluid represent a free boundary transport system, with transport occurring across the semisolid/liquid interface. 

Vaginal cream contains mineral oil and vaginal suppositories contain an oleaginous base which may weaken rubber or latex products such as condoms, avoid use within 72 hr following treatment with vaginal cream or suppositories... 

For most purposes, it is convenient to classify suppository bases according to their physical characteristics into two main categories and a third miscellaneous group (i) fatty or oleaginous bases (ii) water-soluble or water-miscible bases, and (iii) miscellaneous bases, general combinations of lipophilic and hydrophilic substances (43). Appendix V presents a survey of commercial pharmaceutical suppositories and the respective suppository bases. 

Also known as oleaginous bases, the hydrocarbon bases are essentially water-free, incorporating aqueous preparations only in small amounts and with considerable... 

Mineral oil—a mixture of liquid hydrocarbons obtained from petroleum. These are useful as levigating agents to wet and incorporate solid substances (e.g., salicylic acid, zinc oxide) into the preparation of ointments that consist of oleaginous bases as their vehicle. There are two types of mineral oils listed in the US. Pharmacopeia/National Formulary (USP/NF). Mineral oil USP is also called heavy mineral oil with a specific gravity between 0.845 and 0.905 and a viscosity of not less 34.5 cSt (cSt = mm /s) at 40°C. Light mineral oil, NF has a specific gravity between 0.818 and 0.880 and a viscosity of not more than 33.5 cSt. Table 2 lists the commercially available mineral oil fractions. 

When incorporating liquids or solutions of drugs into ointment bases, care must be taken to select the appropriate ointment base with regard to its capacity to accept the volume of drug in solution. To incorporate liquids into hydrophobic bases such as oleaginous bases, the liquid solution must first be incorporated in a minimum amount of hydrophilic base and subsequently added to the hydrophobic base. Care must be taken not to exceed the liquid-retaining capacity of the bases beyond which they become too soft or semiliquid in state. 

Melt the PG 4000 and add the liquid PG 400. Cool with stirring until congealed. Y. Cream base, w/o (rose water ointment, NF 14) Oleaginous phase Spermaceti 12.5%... 

A device was designed for use in studying the release of corticosteroids suspended in an oleaginous ointment base [20], The apparatus consists of a Teflon dish which floats on the surface of the stirred receptor fluid. After the system has been brought to thermal equilibrium, a known amount of ointment is evenly spread on the bottom surface of the Teflon dish. At particular time intervals,... 

Method for oleaginous ointment bases (free boundary method) Mass transport from water-immiscible ointment bases 20... 

Z Chowhan, R Pritchard. Release of corticoids from oleaginous ointment bases containing drug in suspension. J Pharm Sci 64 754, 1975. 

Ointments are semisolid preparations that are intended for external use. Ointments may contain either finely powdered drugs or their mixtures, liquids, and other drug forms incorporated into appropriate bases. They are applied to the skin for their physical effects as emollients (which make the skin more pliable), protectants, lubricants, and drying agents. Ointment bases are also used as vehicles in which to incorporate topical medications which exert specific effect. There are four types of ointment bases, namely, oleaginous, absorption, water removable, and water soluble bases. 

V feter-absorbing capacity of oleaginous and water-in-oil bases can be improved by hydrophilic CDs. 

Many reports have indicated the findings that the effects of CyDs on the rectal delivery of drugs depend markedly on vehicle type (hydrophilic or oleaginous), physicochemical properties of the complexes, and an existence of tertiary excipients such as viscous polymers. The enhancing effects of CyDs on the rectal absorption of lipophilic drugs are generally based on the improvement of the release from vehicles and the dissolution rates in rectal fluids, whereas those of CyDs on the rectal delivery of poorly absorbable drugs such as antibiotics, peptides,... 

Biotechnological transformation is powerful tool to effectively utilize a broad variety of plant oils, with the aim to modify their structure for the production of new lipid-based materials with demanded properties and functions. One method of plant oil transformation is based on the direct utilization by microorganisms. Employed oils can be converted to aimed compounds by submerged cultivation or oils, and/or oleaginous plant materials can be utilized during solid state fermentation to useful bioproducts enriched with demanded microbial products. Another biotransformation technique covers the enzymatic modification of oil components to structured lipids with biological properties. 

Bases are classified based on their composition and physical characteristics. The U.S. Pharmacopeia (USP) classifies ointment bases as hydrocarbon bases (oleaginous... 

Hydrocarbon bases are made of oleaginous materials. They provide emollient and protective properties and remain in the skin for prolonged periods. It is difficult to incorporate aqueous phases into hydrocarbon bases. However, powders can be incorporated into these bases with the aid of liquid petrolatum. Removal of hydrocarbon bases from the skin is difficult due to their oily nature. Petrolatum USP, white petrolatum USP, yellow ointment USP, and white ointment USP are examples of hydrocarbon bases. 

Water-soluble bases do not contain any oily or oleaginous phase. Solids can be easily incorporated into these bases. They may be completely removed from the skin due to their water solubility. Polyethylene glycol (PEG) ointment National Formulary (NF) is an example of a water-soluble base. 

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