Supercritical Fluid Sterilization Method

US006149864A United States Patent [19] [11] Patent Number: 6,149,864 Dill0w et al. [45] Date of Patent: Nov. 21, 2000 [54] SUPERCRITICAL FLUID STERILIZATION FOREIGN PATENT DOCUMENTS METHOD 39 04 513 A1 8/1990 Germany . . . . . WO 97/48848 [75] Inventors: Angela K. Dill0W, Minneapolis, Minn.; A1 12/1997 WIPO . Robert S. Langer, Newton, Mass.; Neil Foster, Ortarmon, Australia; J efi'rey S. OTHER PUBLICATIONS Hrkach> S0merVfl1e> M355 Lin et al. “Inactivation of Saccharomyces cerevisiae by . _ supercritical and subcritical carbon dioxide,” Biotechnol. [73] Assignee: Massachusetts Institute of Pmg. 8:458_461 (1992). Technology, Cambridge, Mass. Primary Examiner—Krisanne Thornton [21] Appl. No‘: 09/104,775 Attorney, Agent, or Firm—Arnall Golden & Gregory, LLP [22] Filed: Jun. 25, 1998 [57] ABSTRACT [51] Int Cl 7 A61L 2/00 A method is provided for sterilizing materials, particularly [52] U.s. Cl. ................................ .. 422/28, 422/32, 422/33 Iggafiyeggfesfig;afgggwfifglggI1rgggigfg;P;§5a;1;g>0;Vg§;;;g;gj [58] Field of Search .................................. .. 422/4, 28, 29, P pressures in the range of 2000 to 3000 psi (140 to 210 bar) and temperatures preferably between 30 and 45° C. for . periods between 20 minutes and six hours, more preferably [56] References Clted between 0.5 and 2 hours. Agitation, pressure cycling, and the Us, PATENT DOCUMENTS presence of water were found to enhance the sterilization method, which promotes diffusion of the supercritical fluid 422/32, 33, 38, 292, 295, 305, 307 4,263,253 4/1981 et al. .................................. .. 422/1 b ~ t th ~ ~ t th b 4348357 9/1982 Bithe“ ~~~~~~~~ ~~ ~~ 422/33 tf1:eC:elSl: k1fif§1Cf§§fa?§2”m°a iiiidi 4,687,635 8/1987 Kaehleretal. .. 422/33 P ’ g " g 5,073,203 12/1991 A1_Ghatta . . . . . . . . . . . . . N 422/33 and frequency of the pressure cycling, as well as the process 5,213,660 5/1993 Hossain et al. .. 162/5 time and temperature, may Vary according t0 the type and 5,723,012 3/1993 pages et a], N 523/15 form of the material to be sterilized and the type of organ- 5,725,579 3/1998 Fages et al. .. 623/16 isms to be killed. 5,869,123 2/1999 Osajima et al. . 426/330 5,877,005 3/1999 Castor et al. ...................... .. 435/286.1 5 Claims, 3 Drawing Sheets 6,149,864 otmzoum ®>_._._mOn_ C._U._O \\ Sheet 1 of 3 .z ._._mo 8_n._._o:amo:n: mz