USOO6426078B1 (12) United States Patent (10) Patent No.: US 6,426,078 B1 Bauer et al. (45) Date of Patent: Jul. 30, 2002 (54) OIL IN WATER MICROEMULSION 5,118,511 A 6/1992 Horn et al. ................. 424/502 5,213,799 A * 5/1993 Goring et al. .............. 424/401 (75) Inventors: Kurt Bauer, Freiburg-Tiengen; FOREIGN PATENT DOCUMENTS Clarissa Neuber, Villingen-Schwenningen; Axel Schmid, GB 2 222 770 3/1990 Gottmadingen-Bietingen; Karl Manfred GB 2 297 759 8/1996 Völker, Freiburg, all of (DE) OTHER PUBLICATIONS (73) Assignee: Roche Vitamins Inc., Parsippany, NJ English language astract of JP 8120187. (US) Derwent Abstract No. AN 86-172070. Patent Abstract of Japan No. JP 59051214. (*) Notice: Subject to any disclaimer, the term of this Patent Abstract of Japan No. JP 07204487. patent is extended or adjusted under 35 Derwent Abstract No. AN 87-040923. U.S.C. 154(b) by 0 days. Patent Abstract of Japan No. JP 09157159. Patent Abstract of Japan No. JP 60137260. (21) Appl. No.: 09/030,714 * cited by examiner (22) Filed: Feb. 26, 1998 Primary Examiner. Theodore J. Criares (30) Foreign Application Priority Data ASSistant Examiner Jennifer Kim Mar. 17, 1997 (CH) .............................................. O628/97 (74) Attorney, Agent, or Firm-Byran Cave LLP (51) Int. Cl. .......................... A61K 6/00; A61K 47/00; (57) ABSTRACT A61K 31/74 The invention is concerned with a microemulsion of the (52) U.S. Cl. .................... 424/401; 424/439; 424/78.03; oil-in water type, containing at least one polyglycerol ester 424/78.04; 514/844 as the emulsifier and at least one lipophilic Substance as the (58) Field of Search ................................. 424/401, 439, internal phase. 424/78.03, 78.04, 455; 514/844 The emulsifier contains a triglycerol monofatty acid ester (56) References Cited and the lipophilic Substance is one from the group caro tenoids, especially, 3-caroteine, Vitamins A, D, E and K and U.S. PATENT DOCUMENTS their derivatives and polyunsaturated fatty acids. 4,835,002 A 5/1989 Wolf et al. ................. 426/590 5,045,337 A 9/1991 El-Nokaly et al. .......... 426/602 55 Claims, No Drawings US 6,426,078 B1 1 2 OIL IN WATER MICROEMULSION ether, available from Gattefosse S.A., France), polyethylene glycols, polyglycerols, monoglycerides or lecithin, espe The invention is concerned with a microemulsion of the cially transcutol, monoglycerides or lecithin, with lecithin oil-in-water type, containing at least one polyglycerol ester being especially preferred. as the emulsifier and at least one lipophilic Substance as the Furthermore, the microemulsion can also contain at least internal phase. one carrier oil. The lipophilic Substance is dissolved at least Certain Substances, which can be used for the manufac in part in the carrier oil, which increases the final content of lipophilic Substance in the finished microemulsion. The ture of a microemulsion, lead to microemulsions which can carrier oil is preferably orange oil, palm oil, a triglyceride, be used without hesitation in foodstuffs or in the pharma Squalane, Squalene, limonene, isopropyl myristate or isopro ceutical or cosmetic field for human beings. For example, in 1O pyl palmitate, especially orange oil, Squalane or limonene, the pharmaceutical field microemulsions have been manu preferably orange oil. factured using tensides as emulsifiers, which contain poly The microemulsion contains as the Vitamin especially oxyethylene residues in the hydrophilic part of the chain. tocopherol and/or VitaminA, especially Vitamin Apalmitate. With the aid of these tensides even fat-soluble Substances, AS the carotenoid the microemulsion preferable contains Such as e.g. Vitamins or pharmaceutically active Substances, 15 all-trans-B-caroteine, 9-cis-B-caroteine, 13-cis-3-caroteine, can be Solubilized in water to give a clear emulsion. B-opo-8-carote nic acid ethyl ester, apocarote nal, However, these emulsifiers can be harmful to health. Use in astaxanthin, canthaxanthin, crocetin or lycopene. A foodstuffs is accordingly prohibited, mainly because these B-caroteine is especially preferred. tensides contain residual monomers which are potentially Preferably, the amount of lipophilic substance, for carcinogenic. example tocopherol, lies at 1-20 wt.%, the amount of Great Britain Patent Publication GB 2,222,770 describes emulsifier lies at 10-99 wt. 76 and the amount of microemulsions having Sugar esters as emulsifiers, which co-emulsifier (when present) lies at 1-89 wt.%, with the contain as essential co-emulsifiers low-molecular polyoxy ratio of emulsifier to co-emulsifier preferably being 50:50 ethylenes which are, however, toxic. wt.%. U.S. Pat. No. 5,045,337 describes for the foodstuff field, 25 The microemulsion can be used especially in foodstuffs, a water-in-oil microemulsion System with polyglycerol in pharmaceutical preparations and in cosmetics. esters or mono-diglycerides as emulsifiers for the formula For foodstuffs, the oil in water microemulsions of the tion of hydrophilic vitamins and flavorants. present invention provide a convenient way to add or fortify U.S. Pat. No. 4,835,002 describes oil-in-water micro a variety of foodstuffs, for examples, beverages, baked emulsions with polyglycerol esters for the formulation of goods, dressing, and the like, with the lipophilic Substances lipophilic edible oils, fragrance-imparting oils or flavor mentioned herein. The Same holds true for pharmaceutical imparting oils, which are proposed for the foodstuff field. compositions and cosmetics. For pharmaceutical The present invention is concerned with an oil in water compositions, the oil in water microemulsions permit the microemulsion which comprises as an emulsifier, at least addition of the lipophilic Substance to pharmaceutical one polyglycol ester, the polyglycol ester being a triglycerol 35 compositions, for example, oral Vitamin Solutions. For monofatty acid ester; at least one lipophilic Substance cosmetics, the oil in water microemulsions permits the Selected from the group consisting of carotenoids, Vitamin A addition of the lipophilic Substances to variety of cosmetics, and its derivatives, vitamin D and its derivatives, vitamin E for example, foundation, lipstick, and the like. and its derivatives, Vitamin K and its derivatives, and In each instance for foodstuff, pharmaceutical, and cos polyunsaturated fatty acids, and combinations thereof; and 40 metic materials, the addition of the lipophilic Substances Water. mentioned herein provide valuable properties to the mate The microemulsion is characterized in that the emulsifier rials as one of ordinary skill in the art will appreciate when contains at least one triglycerol monofatty acid ester and the Such lipophilic Substances are either consumed (foodstuffs lipophilic Substance is Selected from the group of or pharmaceuticals) or are topically applied carotenoids, especially B-caroteine, Vitamins A, D, E and K 45 (pharmaceuticals or cosmetics). For the various foodstuff, and their derivatives and polyunsaturated fatty acids Such as pharmaceutical and cosmetic materials, the amounts of oil in e.g. arachidonic acid, eicosapentaenoic acid and docosa water microemulsion to be added will depend upon the hexaenoic acid. amount of lipophilic Substance that is desired to be added to Derivatives of the Vitamins are, for example, Vitamin A the material and the effect which the lipophilic substance is acetate, Vitamin A palmitate, Vitamin E acetate and the like. 50 to have, for example, antioxidant effect or intaking the Under vitamin E there is to be understood synthetic of recommended daily allowance of the lipophilic Substances. naturals tocopherols. In the case of foodstuffs, by fortifying the foodstuffs with With this microemulsion it is possible to solubilize the the oil in water microemulsion of the present application, the afore-mentioned lipophilic Substances in any amount of lipophilic Substance incorporated by use of the microemul water without changing the microscopic appearance of the 55 sion provides for levels of the lipophilic substance which microemulsion or without breaking the microemulsion. would be greater than that present in the foodstuff without The emulsifiers used are non-toxic and, accordingly, Such the addition of the microemulsion. In the case of cosmetics, microemulsions can be used in foodstuffs. They can also be by adding the microemulsion of the present invention, the used in the pharmaceutical field. Cosmetic formulations are cosmetics can be fortified with many of the lipophilic likewise possible. 60 Substances which are considered useful in treating wrinkles, Preferred triglycerol monofatty acid esters are triglycerol burns, etc. In the case of pharmaceuticals, using the micro monolaurate, triglycerol monocaproate or triglycerol emulsions of the present invention permits valuable formu monocaprylate, especially triglycerol monolaurate or trig lations to be fortified with, for example, the lipophilic lycerol monocaprylate. Substances mentioned herein to make Vitamin Solutions and The microemulsions can be manufactured with or with 65 other medicaments to be prepared. out a co-emulsifier. Preferred co-emulsifiers are ethanol, The microemulsion in accordance with the invention is propylene glycol, transcutol (diethylene gylcol monoethyl especially Suitable for formulations in which the aforemen US 6,426,078 B1 3 4 tioned lipophilic Substances need to be Solubilized as lipo microemulsion was miscible with water in any ratio without philic pharmaceutically active Substances. Thus,