The present invention provides a method and an apparatus for forming particles using supercritical fluid. The method includes the steps of mixing a load material with a first flow of a supercritical fluid in a first mixing chamber having a primary mixing device disposed therein to form a melt, transferring the melt from the first mixing chamber to a second mixing chamber having a secondary mixing device disposed therein, mixing the melt with a second flow of the supercritical fluid in the second mixing chamber to form a lower viscosity melt, expanding the lower viscosity melt across a pressure drop into an expansion chamber that is at a pressure below the critical pressure of the supercritical fluid to convert the supercritical fluid to a gas and thereby precipitate the load material in the form of particles.