POLYGLYCEROL ESTERS IN PHARMACEUTICAL PREPARATIONS 481 ...... • . . .' '."c":•' •""• '..•":.:.'.:.." .'.:::.:...:V.%.•:•...•:• ..................... •0•o-0 •-•-o .'::. ............... .:::...... .... ' NEOBE.E 0 . . ß • : '• :. •: .: ....... • .. • .... . '•-• .... •=•.: ..- •.o:•--•..2%'.:.•..•:•:=•: '.: ...... ..•- - ' ..... • ' :•':::":• •" '•,• ".•4•.•:• ........... ... . ..... . ....... . .... Figure &--Stability of emulsions prepared with Neobee O. primarily those containing polyoxyethylene. One of these problems is the interference that has been frequently reported between ethoxylated emulsifiers and bacteriostats of the bisphenol type, such as Hexachloro- phene,* or of the alkyl parahydroxybenzoates (2-7). It was, therefore, decided to use zone of inhibition tests to compare several of the polyglyc- erol esters with other nonionic surfactants. To date, these tests have been run using a 0.5% alcoholic solution of Hexachlorophene with eight different emulsifiers at concentrations up to 2%. Test organisms include two gram negative bacteria (Escherichia coli and Pseudomonas aeruginosa) and a mold (/Ispergillus niger). Tests using gram positive organisms will be published at a later date. The results in Table V suggest that the poly- glycerol esters show promise of being less likely to interfere with Hexa- chlorophene than other nonionic emulsifiers. Further experiments to substantiate these results are now being undertaken. 3. Many other applications of the polyglycerol esters are possible as a result of their unique chemical and physical properties. Thus, the stea- rates can be used as gelling agents for mineral oils, vegetable oils and gly- cols. For instance, decaglycerol monostearate will gel mineral oil, and the resulting gel can be readily rinsed with water. Materials such as decaglycerol tristearate and polyglycerol oleates can be used to formulate * G-11©--Sindar Corporation, Delawanna, N.J. (7).

482 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS TABLE VI--CoMPOSlTION OF EMULSIONS PREPARED WITH POLYGLYCEROL ESTEKS Formula #1 (Vegetable Oil Emulsion) Neobee 54* .................... 6% Decaglycerol decaoleate ......... 5% Decaglycerol decastearate ........ Neobee t .................... 45% Water ........................ 39% Formula//3 (Mineral Oil Emulsion) Mineral oil (50--60 risc.) ........ 38% Petrolatum ................... Decaglycerol decastearate ........ 3% Decaglycerol tetraoleate ......... 5% Lanolin ........................ Beeswax ....................... 3% Magnesium stearate ............. Water ...................... 32.6% Borax ...................... 0.4% Formula//5 (Cosmetic Emulsion) Isopropyl myristate ............. Cetyl alcohol .................. .4/0 Decaglycerol tetraoleate ......... l Decaglycerol mono61eate ......... Stearic acid .................. 18% Spermaceti ..................... Glycerol ....................... 4% Hexachlorophene ............. 0.5% Water ...................... 66.5% Formula #2 (Peanut Oil Emulsion) Beeswax: ..................... Neobee 54* .................... 3% Magnesium stearate ............ 1% Decaglycerol decaoleate ...... 10% Peanut oil .................... 45% Borax ....................... 0. Water ..................... 37.8% Formula//•t (Mineral Oil Emulsion) Mineral oil ................... 25% Petrolatum ........... 25% Decaglycerol decaoleate ......... Decaglycerol decalinoleate ....... 3% Beeswax ....................... 7% Glycerol ...................... 3% Borax ....................... 0.5% Water ...................... 32. Formula//6 (Cosmetic Emulsion) Neobee M5 :• ................... 3% Cetyl alcohol ................. Decaglycerol decalinoleate ....... Decaglyce• ol monopalmitate ..... 4% Drewmulse 1128{} ............... 8% Cabosil©[[ ..................... 1% Glycerol ....................... 3 % Water ....................... 73 % * Glyceryl tripalmitate (Drew Chem. Corp.). t Modified coconut triglyceride (Drew Chem. Corp.). :[: Modified coconut triglyceride (Drew Chem. Corp.). {} Self-emulsifying glyceryl monostearate (Drew Chem Corp.). [[ A grade of silica manufactured by G. L. Cabot Co. 'I-ABLE V---ZONES OF INHIBITIO•q Emulsifier E. coli Ps. aeroginosa d. niger , Concentration of Emulsifier Used 0 o. 5% 1.0% 2.0% 0 o. 5% 1.0% 2.0% 0 0.5% 1.0% 2.0% POE Sorbitan mono61eate 7 - - - 5 - - - 8 POE Sorbitan monolaurate .. 5 - - .. - - - .. -' POE (39) stearate .. - - - .. - - - .. - - POE (23) laurylalcohol .. - - - .. - - - .. - - - Decaglycerol mono61eate* .. 10 12 10 .. 3 2 - .. 6 6 6 Decaglycerol monolaurate* .. 15 15 10 .. 5 3 2 .. 6 8 7 Decaglycerol monopalmitate* .. 12 8 10 .. 5 2 1 .. 6 6 7 Hexaglycerol monoiJleate* .. 20 10 5 .. 5 1 - .. 9 7 3 All tests were run using 0.5% G-11 in alcoholic soluiion, with and without emulsifiers. - indicates no inhibition. Numbers indicate the zone of inhibition in ram. * Please note that no precipitate occurred in alcohol at these concentrations of emulsifier.