Tray apparatus for freeze-drying biologicals having a predetermined unit dosage

• US 4,501,719 A
• Filed: 07/30/1982
• Issued: 02/26/1985
• Est. Priority Date: 05/04/1981
• Status: Expired due to Term

• Current Assignee: Vital Signs Incorporated (Becton Dickinson & Co)
• Original Assignee: Vital Signs Colorado, Inc. (Becton Dickinson & Co)
• Inventors: Williams, Charles D.
• Primary Examiner(s): NOT, DEFINED
• Assistant Examiner(s): Carrier, Joseph P.
• Application Number:
  US06/403,862
• Time in Patent Office: 942 Days
• Field of Search: 422/102, 422/104, 422/99, 435/300, 435/301, 435/298, 436/809, 34/201, 34/237, 34/238
• US Class Current: 422/552
• CPC Class Codes: B01L 3/5085 for multiple samples, e.g. microtitration plates
• CPC Class Codes: F02B 3/06 with compression ignition compression ignition engines using air or gas for blowing fuel into compressed air in cylinder F02B13/02
• CPC Class Codes: F26B 5/06 the process involving freezing
• CPC Class Codes: G01N 2035/00445 Other cooling arrangements
• CPC Class Codes: Y10S 436/809 Multifield plates or multicontainer arrays

Abstract

A tray having a plurality of wells bored or formed therein of predetermined volume for use in a freeze drying process is disclosed. The wells contain a solution of biologicals of predetermined concentration. The tray is thermally configured to maximize freezing efficiency during the lypholization or freeze-drying process. A pledget product is formed by the freeze drying process, the pledget adapted to be used in a single dosage of a predetermined unit value. The pledget can be stored for extended periods of time in a syringe and then be readily utilized in heparinizing an aspirated blood sample.

Claims

1. Tray apparatus for lyophilizing a solution of biological material into pledgets of predetermined unit dosages of the biological material for use in a freeze drying apparatus having a chamber within which is positioned a plurality of spaced apart superposed thermally controlled shelves, comprising:

an upper plate having a length, a width and a thickness and having a plurality of wells extending downwardly from a portion of an upper surface thereof into said upper plate, each of said wells being conical, having downwardly sloping, converging side walls, and terminating in a concave dome shape and having a volume substantially equal to the volume of a solution of the biological material in a liquid, said solution being of such concentration and volume as to yield, upon lyophilization, the predetermined unit dosage size of pledget, each well terminating at a location spaced from a lower continuous surface of said upper plate;

a lower plate having a length, a width and a thickness, an upper continuous surface of said lower plate laminated to said lower continuous surface of said upper plate in a thermally conductive manner, said lower plate comprising a material having a greater thermal conductivity than the material comprising said upper plate;

a sheet of thermal insulating material having a length, a width and a thickness, said thermal insulating material having a continuous lower surface with a surface area substantially equal to or greater than the surface area of said upper surface of said upper plate, said lower surface of said thermal insulating material positioned above said upper surface of said upper plate to establish a thermal gradient through said upper plate wherein lower points in the wells are at lower temperature than upper points in the wells to insure that said solution freezes from the bottom to the top, said thermal insulating material having a lower thermal conductivity than either said upper or lower plates; and

,

a separator comprising a continuous rigid sheet positioned between said thermal insulating material and said upper plate, said separator having a lower surface with a surface area substantially equal to or greater than the surface area of said portion of said upper surface of said upper plate from which said plurality of wells extend.