Patent ID: 7605231

Claim:
A high-molecular weight micelle which comprises a gelatin derivative that is gelatin covalently bonded to organic compounds, wherein the organic compounds, before covalently bonding with the gelatin, are: (i) at least one compound selected from the group consisting of an alkyldiamine, an alkyldicarboxylic acid, and an aminoalkylcarboxylic acid, and (ii) a polyethylene glycol derivative represented by the following formula (1): wherein R is a straight or branched alkyl group or alkenyl group both having 1 to 24 carbon atoms, OA is an oxyalkylene group having 3 to 4 carbon atoms, the oxyalkylene group and an oxyethylene group may be added in the block state or randomly, a and b are respectively an average addition mole number of oxyalkylene group and that of the oxyethylene group, and satisfy the following formulas; 0≦a≦200, 4≦b≦2000, and a/(a+b)≦0.5, Z is O or OC(O)and m is an integer of 0 to 3, and the micelle has a grain diameter of 20 to 500 nm.