Cavitation seed for drug delivery, and drug delivery method using same

A method for delivering drugs to the epidermis of a living body by using cavitation seeds, comprising the steps of:

• (a) introducing to the epidermis a mixture including the cavitation seeds mixed with a fluid including the drugs;
• (b) adjusting electromagnetic field applied to the mixture to thereby determine positions of the cavitation seeds in the mixture;
• and
• (c) irradiating ultrasound waves onto the mixture by using an ultrasound radiator to induce cavitation of the cavitation seeds,
• wherein each of the cavitation seeds comprises:
• a shell which forms an outer surface thereof to maintain the outer shape thereof in the mixture;
• and
• a core which is positioned inside the shell and which determines buoyancy of the cavitation seeds in the mixture,
• wherein each of the cavitation seeds induces cavitation by the ultrasound waves irradiated onto the mixture, and
• wherein the shell comprises (I) at least one neutral phospholipid selected from a first group consisting of DLPC (1,2-Dilauroyl-sn-glycero-3-phosphocholine), DMPC (1,2-Dimyristoyl-sn-glycero-3-phosphocholine), DPPC (1,2-Dipalmitoyl-sn-glycero-3-phosphocholine), DSPC (1,2-Distearoyl-sn-glycero-3-phosphocholine), DOPC (1,2-Dioleoyl-sn-glycero-3-phosphocholine), DMPE (1,2-Dimyristoyl-sn-glycero-3-phosphoethanolamine), DPPE (1,2-Dipalmitoyl-sn-glycero-3-phosphoethanolamine), DOPE (1,2-Dioleoyl-sn-glycero-3-phosphoethanolamine) and (II) at least one negative polar phospholipid selected from a second group consisting of DMPA-Na (1,2-Dimyristoyl-sn-glycero-3-phosphate), DPPA-Na (1,2-Dipalmitoyl-sn-glycero-3-phosphate), DOPA-Na (1,2-Dioleoyl-sn-glycero-3-phosphate), DMPG-Na (1,2-Dimyristoyl-sn-glycero-3-Phosphoglycerol), DPPG-Na (1,2-Dipalmitoyl-sn-glycero-3-Phosphoglycerol), DOPG-Na (1,2-Dioleoyl-sn-glycero-3-Phosphoglycerol), DMPS-Na (1,2-Dimyristoyl-sn-glycero-3-phosphoserine), DPPS-Na (1,2-Dipalmitoyl-sn-glycero-3-phosphoserine), DOPS-Na (1,2-Dioleoyl-sn-glycero-3-phosphoserine), DOPE-Glutaryl-(Na)2(1,2-Dioleoyl-sn-glycero-3-phosphoethanolamine), Tetramyristoyl Cardiolipin-(Na)2, DSPE-mPEG-2000-Na (1,2-Distearoyl-sn-glycero-3-phosphoethanolamine), DSPE-mPEG-5000-Na, DSPE-Maleimide PEG-2000-Na, and DOTAP-C1(1,2-dioleoyl-3-trimethylammonium propane).