The variable toxicity of silver ions in cell culture media

TY - JOUR

T1 - The variable toxicity of silver ions in cell culture media

AU - Souter, Paul Mark

AU - Cunningham, Jim C.

AU - Horner, Alan

AU - Genever, Paul Gilbert

N1 - © 2019 Published by Elsevier Ltd. This is an author-produced version of the published paper. Uploaded in accordance with the publisher’s self-archiving policy.

PY - 2019/10/1

Y1 - 2019/10/1

N2 - The elevated interest in silver ions (Ag+) as a broad spectrum antimicrobial for use on medical devices has increased the number and importance of in vitro biocompatibility testing, however little consideration is given to the culture environment in which the assessments are performed. The current investigation assessed the viability of mouse fibroblasts (L929) exposed to different concentrations of Ag+ in both Dulbecco's modified Eagle's medium (DMEM) and minimal essential medium Eagle, alpha modification (αMEM). We identified a significant increase in the EC50 of L929 cells exposed to Ag+ in αMEM compared to DMEM, which was matched by a corresponding decrease in Ag+ availability in αMEM at concentrations ≤400 μM, as detected by inductively coupled plasma mass spectrometry (ICP-MS). The reduced availability was not observed for Ag+ > 400 μM, the concentration above which caused in vitro cytotoxicity in L929 cells in αMEM; while linear quantification of Ag+ was observed in DMEM. Equilibration of the chloride and glucose components between media did not affect cytotoxicity on primary test cells; mesenchymal stromal cells (MSCs). Overall, our results present evidence of the importance of culture conditions on the in vitro evaluation of silver, with DMEM providing a reliable basal media in which to conduct assessments.

AB - The elevated interest in silver ions (Ag+) as a broad spectrum antimicrobial for use on medical devices has increased the number and importance of in vitro biocompatibility testing, however little consideration is given to the culture environment in which the assessments are performed. The current investigation assessed the viability of mouse fibroblasts (L929) exposed to different concentrations of Ag+ in both Dulbecco's modified Eagle's medium (DMEM) and minimal essential medium Eagle, alpha modification (αMEM). We identified a significant increase in the EC50 of L929 cells exposed to Ag+ in αMEM compared to DMEM, which was matched by a corresponding decrease in Ag+ availability in αMEM at concentrations ≤400 μM, as detected by inductively coupled plasma mass spectrometry (ICP-MS). The reduced availability was not observed for Ag+ > 400 μM, the concentration above which caused in vitro cytotoxicity in L929 cells in αMEM; while linear quantification of Ag+ was observed in DMEM. Equilibration of the chloride and glucose components between media did not affect cytotoxicity on primary test cells; mesenchymal stromal cells (MSCs). Overall, our results present evidence of the importance of culture conditions on the in vitro evaluation of silver, with DMEM providing a reliable basal media in which to conduct assessments.

KW - Culture media

KW - EC

KW - L929 fibroblasts

KW - Mesenchymal stromal cells

KW - Silver

UR - http://www.scopus.com/inward/record.url?scp=85066269586&partnerID=8YFLogxK

U2 - 10.1016/j.tiv.2019.05.015

DO - 10.1016/j.tiv.2019.05.015

M3 - Article

SN - 0887-2333

VL - 60

SP - 154

EP - 159

JO - Toxicology in vitro

JF - Toxicology in vitro

ER -