Directional solidification for the controlled freezing of biomaterials

An apparatus (10) for the controlled freezing of a material (12), comprising:

• a longitudinally extending substrate (14) having a thickness, .delta., a leading end (16), a trailing end (18), a first surface (24), and a second surface (26), said second surface 26 being adapted to support an aliquot of said material (12) thereon;
• a first base (30) having a first heat transfer surface (32) adapted to sit in heat transfer relation with said first surface (24);
• first temperature control means (34) for controlling the temperature, T.sub.H, of said first base (30) to be above the freezing temperature of said material (12);
• a second base (36) spaced longitudinally a distance, d, from said first base (30) to define a gap (38) therebetween and having a second heat transfer surface (40) adapted to sit in heat transfer relation with said first surface (24);
• second temperature control means (42) for controlling the temperature, T.sub.C, of said second base (36) to be below the freezing temperature of said material (12);
• and
• moving means (44) for moving said substrate (14) generally longitudinally across said first base (30) in the direction of said second base (36) with said first surface (24) in heat transfer relation with both said first heat transfer surface (32) and said second heat transfer surface (40).