Medium evaluation method, medium, and culture method

Patent metadata

Field	Value
Publication number	US-2019219492-A1
Application number	US-201916364186-A
Country	US
Kind code	A1
Filing date	Mar 26, 2019
Priority date	Sep 30, 2016
Publication date	Jul 18, 2019
Grant date	—

Abstract

Provided is a medium evaluation method for evaluating the suitability of a medium in which cell aggregates are cultured in a suspended state, by which an evaluation of whether a medium is adequate for both the cell retention performance and the cell recovery efficiency, the medium evaluation method including dispersing a plurality of particles in a medium, measuring a sedimentation velocity by which the particles settle in the medium, and using the sedimentation velocity thus measured as an index value indicating the suitability of the medium; and also provided are a medium and a culture method.

First claim

What is claimed is:

1 . A medium evaluation method for evaluating the suitability of a medium in which cell aggregates are cultured in a suspended state, the method comprising:
dispersing a plurality of magnetic particles in a medium contained in a container; measuring a predetermined distance x in which the number ratio of the particle numbers obtained before and after the application of a magnetic field of the magnetic particles included in the range of a predetermined region starting from a predetermined distance from the source of magnetic field generation, is a predetermined value; and using the distance x thus measured as an index value indicating the suitability of the medium.

2 . The medium evaluation method according to claim 1 , wherein the range of the predetermined region is the range of from 3 times to 100 times the particle size of the magnetic particles.

3 . The medium evaluation method according to claim 1 , wherein magnetic polylactic acid particles having a particle size of 100 μm, a density of 1.4 g/cm 3 , and a magnetite percentage content of 40% are used as the magnetic particles.

4 . The medium evaluation method according to claim 1 , wherein the application of a magnetic field is carried out by disposing a magnet having a surface magnetic flux density of from 150 mT to 250 mT on a predetermined unidirectional surface of the container.

5 . The medium evaluation method according to claim 1 ,
wherein magnetic polylactic acid particles having a particle size of 100 μm, a density of 1.4 g/cm 3 , and a magnetite percentage content of 40% are used as the magnetic particles, the application of a magnetic field is carried out by disposing a magnet having a surface magnetic flux density of 200 mT on a predetermined unidirectional surface of the container, and the medium having an index value thus measured in a predetermined range is determined as an adequate medium.

6 . The medium evaluation method according to claim 5 , wherein an upper limit of the predetermined range is a value that has been predetermined based on a retention performance by which a medium retains the cell aggregates.

7 . The medium evaluation method according to claim 5 , wherein a lower limit of the predetermined range is a value that has been predetermined based on a recovery efficiency of recovering cell aggregates from a medium.

8 . The medium evaluation method according to claim 5 , wherein the range of the predetermined region is the range of from 3 times to 100 times the particle size of the magnetic particles.

Assignees

• Fujifilm Corp

Inventors

• Ling Xiao
• Hashimoto Kiyokazu
• TOMIKAWA Haruki

Classifications

• G01N15/04 Primary

  Investigating sedimentation of particle suspensions · CPC title

• G01N2015/0042

  Investigating dispersion of solids · CPC title

• G01N27/72

  by investigating magnetic variables · CPC title

• G01N33/5005 Primary

  involving human or animal cells (immunoassay G01N33/56966; immunoassays of protozoa G01N33/56905; protozoa in screening assays C12Q1/025) · CPC title