A MICROEMULSION PREPARATION OF HIGH CONCENTRATION PROPOFOL FOR ANESTHETIC USES

摘要

The present invention relates to a self-microemulsifiable anhydrous base composition for use in the preparation of a spontaneously formed and thermodynamically stable microemulsion that can be used as an anesthetic composition, comprising, liquid propofol; and, a nonionic surfactant consisting of polyoxyethylene (POE) having the structure of [POE(n)] subm-R'- R; where POE (n) is a polyoxyethylene moiety of -mer number n, and having m of these POE functional groups attached to R'; where the value of m is one to three; where R' is a linking moiety selected from glyceryl, sorbitan, ester, amino, or ether functions; where R is a hydrophobic moiety consisting of saturated or unsaturated alkyl or alkylphenyl groups; and where the structure of the nonionic surfactant is further defined by a ratio of A, the total number of POE -mer units in the surfactant given by the product of -mer number n and total POE chain number m per molecule, to B, the number of carbons in the hydrophobic functional group R, the ratio of A/B being in the range of 1 to 2 or in the range of 0.7 to 4; and wherein the nonionic surfactant is included in the base composition in a concentration of eight (8) parts or more of the nonionic surfactant to one (1) part of propofol, with the base composition not containing any other surfactant other than said nonionic surfactant having said structure, and with the base composition not containing a co-solvent.