Cryopreservative compostions and methods

Abstract

This disclosure describes compositions and methods related to cryoprotection of biomaterial. Generally, the cryoprotective composition includes a cryoprotective agent and magnetic nanoparticles effective for thawing a cryopreserved specimen comprising biomaterial with minimal biomaterial damage. In some embodiments, the composition is effective for thawing a cryopreserved specimen having a minimum dimension of 0.1 mm. Generally, the method includes obtaining a biomaterial cryopreserved with a cryoprotective composition as summarized above, then subjecting the cryopreserved biomaterial to electromagnetic energy of an intensity sufficient to excite the magnetic nanoparticles and thaw the biomaterial.

1 . A cryoprotective composition comprising:
 a cryoprotective agent and magnetic nanoparticles effective for thawing a cryopreserved specimen comprising biomaterial with minimal biomaterial damage.   
     
     
         2 . The composition of  claim 1  wherein the cryopreserved specimen has a minimum dimension of 0.1 mm. 
     
     
         3 . The composition of  claim 1  wherein the cryoprotective agent has a molarity of no more than 9 M. 
     
     
         4 . The composition of  claim 1  wherein the magnetic nanoparticles comprise superparamagnetic nanoparticles. 
     
     
         5 . The composition of  claim 1  wherein the magnetic nanoparticles comprise ferromagnetic nanoparticles. 
     
     
         6 . The method of  claim 1  wherein the total concentration of magnetic nanoparticles comprises 0.01 mg Fe/mL to 100 mg Fe/mL. 
     
     
         7 . The composition of  claim 1  wherein the damage comprises cracking 
     
     
         8 . The composition of  claim 1  wherein the damage comprises devitrification. 
     
     
         9 . The composition of  claim 1  wherein minimal damage comprises sufficiently minimal structural damage to the biomaterial that the biomaterial is suitable for transplantation. 
     
     
         10 . A composition comprising:
 a biomaterial perfused with a cryoprotective composition comprising:
 a cryoprotective agent; and 
 magnetic nanoparticles effective for thawing a cryopreserved specimen comprising biomaterial with minimal biomaterial damage. 
   
     
     
         11 . The composition of  claim 10  wherein the biomaterial comprises an organ or portion thereof, a tissue or portion thereof, or cells. 
     
     
         12 . A composition comprising:
 a biomaterial suspended in a cryoprotective composition comprising:
 a cryoprotective agent; and 
 magnetic nanoparticles effective for thawing a cryopreserved specimen comprising biomaterial with minimal biomaterial damage. 
   
     
     
         13 . The composition of  claim 12  wherein the biomaterial comprises an organ or portion thereof, a tissue or portion thereof, or cells. 
     
     
         14 . A method of thawing a cryopreserved biomaterial, the method comprising:
 obtaining a biomaterial cryopreserved with a cryoprotective composition comprising:
 a cryoprotective agent; and 
 magnetic nanoparticles effective for thawing a cryopreserved specimen comprising biomaterial with minimal biomaterial damage; and 
   subjecting the cryopreserved biomaterial to electromagnetic energy of an intensity sufficient to excite the magnetic nanoparticles and thaw the biomaterial.   
     
     
         15 . The method of  claim 14  wherein the electromagnetic energy comprises a radio frequency field, an alternating magnetic field, or a rotating magnetic field. 
     
     
         16 . The method of  claim 15  wherein the radio frequency field, alternating magnetic field, or rotating magnetic field comprises a frequency of 0 kHz to 10 MHz. 
     
     
         17 . The method of  claim 14  wherein the cryopreserved biomaterial is perfused with the cryoprotective composition. 
     
     
         18 . The method of  claim 14  wherein the cryopreserved biomaterial is suspended in the cryoprotective composition. 
     
     
         19 . The method of  claim 14  wherein the cryopreserved biomaterial has a volume with a minimum dimension of at least 0.1 mm. 
     
     
         20 . The method of  claim 14  wherein the cryopreserved biomaterial is thawed with minimal damage. 
     
     
         21 . The method of  claim 20  wherein the damage comprises devitrification. 
     
     
         22 . The method of  claim 20  wherein the damage comprises cracking 
     
     
         23 . The method of  claim 14  wherein the cryopreserved biomaterial is warmed at a rate of at least 10° C./minute throughout. 
     
     
         24 . The method of  claim 14  wherein subjecting the cryopreserved biomaterial to electromagnetic energy of an intensity sufficient to thaw the cryopreserved biomaterial generates a thermal gradient of no more than 1° C./mm within the biomaterial.