Pre-Experimental Wet Heat Sterilization Alters the Ecotoxicity of Pristine Graphene Oxide Toward Daphnia magna.

In a study published on November 28, 2025 by Nanomaterials (Basel), researchers investigated the ecotoxicity of pristine graphene oxide (GO) towards Daphnia magna after pre-experimental wet heat sterilization. The study aimed to understand if sterilization could affect GO's toxicity in aquatic organisms, a concern in various medical and industrial applications.

The researchers subjected pristine GO to two different wet heat sterilization cycles (121°C for 15 minutes and 134°C for 5 minutes) before exposing Daphnia magna, a common water flea often used in ecotoxicity studies, to varying concentrations of the treated GO.

The study found that pre-experimental wet heat sterilization significantly altered the toxicity of pristine GO towards Daphnia magna. In both sterilization cycles, the LC50 (concentration causing 50% mortality) increased compared to the untreated GO, indicating reduced toxicity after sterilization. The highest increase was observed with the 121°C cycle, where the LC50 rose from 3.89 mg/L for untreated GO to 6.74 mg/L for sterilized GO.

The study took place in a laboratory setting and did not involve any specific hospital or clinical departments. The research highlights the potential impact of sterilization processes on the ecotoxicity of certain nanomaterials, such as pristine graphene oxide, and could have implications for their safe use in medical and industrial applications.