Emulsions, Phenolphthalein

A prescription requires gr ii of phenolphthalein in fi iv of an emulsion. If the patient takes 2 tbsp of the emulsion at bedtime, how many milligrams of phenolphthalein does this dose represent ... 

Solubility in water. Transfer 1.0 ml of the mixture by means of a calibrated dropper or a small pipette into a small graduated test tube add 1 ml of water and shake. Observe whether there is complete or partial solution and if there is any sign of chemical reaction. If solution is not complete, add more water (in 1 ml portions) and note (a) if the mixture dissolves completely, and (b) if a portion is insoluble and, if so, whether it is heavier or lighter than the aqueous layer. If an emulsion is formed, it may be assumed that at least one component of the mixture is insoluble in water and at least one component is soluble. Test the aqueous layer obtained with litmus and with phenolphthalein if there is an acid reaction, test also with 5 per cent sodium hydrogen carbonate solution. 

Orciprenaline Aerosol Inhalation Phenolphthalein BPC As for Ergotamine Aerosol Inhalation BPC Microcrystalline phenolphthalein to be used in Liquid Paraffin Emulsion with Phenolphthalein BPC to prevent sedimentation of the phenolphthalein... 

Summary Water-in-silicone oil emulsions, stabilized by silicone-polyether surfactants, are marginally permeable to polar, but uncharged, molecules such as phenolphthalein and crystal violet. However, charged compounds, including these compounds in basic and acidic pH regimes respectively, and proteins transfer much less readily from the internal water phase to external bulk water. Transfer experiments were followed colorimetrically. These experiments shed light on the possible mechanisms by which proteins may be released from these emulsions in bioactive form simple breaking of the emulsion does not appear to be the mechanism of action. 

Phenolphthalein. There are two methods for the determination of phenolphthalein in emulsions. 

Mix 10 ml. of emulsion containing 30 mg of phenolphthalein in a 50 ml. flask with 30 ml. of 96 per cent ethanol. After the two layers have separated make up the solution to the mark with ethanol and mix. After settling add... 

Add the same amount of emulsion in a separatory funnel to 20 ml. of warm glacial acetic acid. Shake the mixture for 5 min, separate the lower layer and transfer to a 50-ml. flask and further extract the remaining oil and emulsifier with two 10-ml. portions of warm glacial acetic acid. Make up the combined extracts to 50 ml. with acetic acid, and transfer an aliquot corresponding to 1-5 mg of phenolphthalein into another separatory funnel. Make up with glacial acetic acid to 2-5 ml., add 3-0 ml. of 5 M sodium acetate and dilute with water to 20 ml. Extract the solution with 20 ml. of petroleum ether to separate the oil dissolved in acetic acid. Separate the lower aqueous phase and, after deaeration, record the polarographic... 

Bond and Druce were able to apply their method (p. 403) successfully for determination of oil in emulsions to paraffin preparations. In the presence of phenolphthalein the second water wash is replaced by 15 ml of0-5N sodium hydroxide. 

The ethanol coagulation technique (p. 402) is particularly suitable for paraffin emulsions since fatty acids are absent and no portion of the oil is lost by solubility in the ethanol the coagulated gums absorb the oil which can be recovered by extraction with ether. To prevent the coagulum becoming horny during filtration and difficult to extract, kaolin is added. Washing of the ethereal extract from impurities is not necessary unless phenolphthalein is present but it avoids evaporation of a quantity of aqueous ethanol extracted by the ether. 

Emulsion of Liquid Paraffin and Phenolphthalein, B.P.C. Contains 50 per cent of liquid paraffin, emulsifying agent, flavouring, and 0 34 per cent w v of phenolphthalein. The assay for liquid paraffin is the same as above except that the ethereal extracts are washed first with 15 ml 0-5N sodium hydroxide and then with 15 ml water. 1 to 2 mg of phenolphthalein may be absorbed in the coagulated solids. 

A volumetric determination of phenolphthalein in mineral oil emulsion has been developed by Warren, Logun and Thatcher based on the iodi-nation of phenolphthalein in an alkaline medium. The emulsion is broken by the addition of acidified solution of sodium chloride, the coagulum... 

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