Medizinprodukte Prüfungen >> Validierte Methoden >> Elution Test

In vitro Cytotoxicity Assay: Elution Test

Sidebar Image

In vitro Cytotoxicity Assay: Elution Test

(mouse cell line L929)


This in vitro method analyzes the cytotoxic potential of the test item microscopically according to USP 41, Chapter <87>.

Pre-seeded cells are cultured with an extract of the test material and thereafter the biological reactivity of the cells is examined after a treatment period of 48 h.

Elution Test

Assessment of growth inhibition of cells by extraction method and microscopic evaluation

  • The test item is extracted under agitation for 24 h in MEM supplemented with 10% FBS at 37 ± 1°C.
  • At the end of the incubation period, the cells are examined microscopically for morphological changes. The biological reactivity (cellular degeneration and malformation) is described and rated on a scale of 0 to 4 (see Table). The responses of the cell cultures treated with the extract of the test item and the controls are evaluated.
  • The test item meets the requirements of the test, if the response to the test item extract is not greater than grade 2 (mildly reactive).




Conditions of all Cultures



Discrete intracytoplasmic granules; no cell lysis



Not more than 20% of the cells are round, loosely attached, and without intracytoplasmic granules; occasional lysed cells are present



Not more than 50% of the cells are round and devoid of intracytoplasmic granules; no extensive cell lysis and empty areas between cells



Not more than 70% of the cell layers contain rounded cells or are lysed



Nearly complete destruction of the cell layers




Cell line

L929 cells (ATCC No. CCL1, NCTC clone 929 (connective tissue mouse), clone of strain L (DSMZ))


Microscopic evaluation

Extraction time

24 h

Incubation time

48 h

Quality controls

Solvent Control: MEM 10% FBS

Negative control: high-density polyethylene material (HDPE)

Positive control: 0.1% Zinc-diethyldithiocarbamate (ZDEC), 0.25% Zinc-dibutyldithiocarbamate (ZDBC)

Data delivery

Biological Reactivity of test material according to USP 41, Chapter <87>

Positive prediction

The test item meets the requirements of the test, if the response to the test item extract is not greater than grade 2 (mildly reactive)



  1. Guess, W.L.; Autian, J. (1966). Toxicity Evaluation of Lexan, Kyonar, Rilsan, Short-Term Studies. Journal of Oral Therapeutics and Pharmacology Vol 3, No.2, pp 116 – 123
  2. United States Pharmacopeia and National Formulary (USP 41), Chapter <87> (2018). Biological Reactivity Tests, in vitro - Elution Test