US 5316540

Patent Overview — US 5,316,540

Title: Apparatus and method for separating microscopic units in a substantially continuous density gradient solution

Patent number: US 5,316,540 A

Application number: US 08/003,559

Inventors: John D. McMannis; Nicholas London

Original assignee: Cobe Laboratories Inc. (current assignee listed as Terumo BCT Inc.)

Key dates: Priority/filing date 1993-01-13; granted and published 1994-05-31. Status listed as expired – lifetime, with anticipated expiration 2013-01-13. A related filing, US 08/180,433 (US 5,368,542 A), shares the 1994-01-12 priority.

Purpose: The invention generally relates to separating microscopic units (e.g., particular types of cells or cell clusters) from a fluid medium by centrifugation in a substantially continuous density gradient solution. Centrifugation is described as relying on constituents assuming a particular radial position within a centrifuge bowl based on their respective densities, thereby separating when rotated at an appropriate angular velocity for an appropriate period.

Plain-language scope (from the supplied text): The described system uses a variable-volume centrifuge, notably the COBE 2991™ Cell Processor (subject of U.S. Pat. No. 3,737,096 to Jones et al., issued Jun. 5, 1973). A flexible diaphragm divides the bowl into upper and lower chambers; a flexible processing bag sits in the upper chamber and holds the medium to be centrifuged. The bag connects to sources and collectors via tubing and a centrally located rotating seal. The lower chamber varies the upper chamber's volume, enabling on-line, sequential harvesting of fractions. The text also notes sterility advantages and mentions pancreatic islet harvesting, infertility, transplantation, and diabetes contexts. Classification is B04B5/04 (radial chamber centrifuges, including flexible receptacles).

Source: https://patents.google.com/patent/US5316540/en

What the excerpt does not establish: It does not provide the full claims, a complete description, a claims-by-claims scope, or the full abstract; therefore the precise metes and bounds of the claimed invention cannot be determined from this excerpt. It also does not establish ownership-transfer details, validity, litigation, or prior-art comparisons beyond the references named above.