Microplastics destabilize lipid membranes by mechanical stretching.

Area of Science:

• Environmental Science
• Biophysics
• Cell Biology

Background:

• Millions of tons of plastic enter oceans annually, leading to widespread microplastic contamination.
• Microplastics are increasingly found in living organisms, including humans, raising health concerns.
• The precise health impacts of ingested microplastics remain under investigation.

Purpose of the Study:

• To investigate the physical mechanism by which microplastics affect cell lipid membranes.
• To quantify the impact of adsorbed microplastic particles on membrane tension and lifetime.

Main Methods:

• Utilized a combination of experimental and theoretical approaches.
• Employed the aspiration micropipette technique on red blood cells to demonstrate mechanical stretching.
• Studied model cell lipid membranes with adsorbed micrometer-sized microplastic particles.

Main Results:

• Adsorbed microplastic particles significantly increase membrane tension, even at low concentrations.
• Each particle consumes membrane surface area, leading to cumulative effects.
• Increased membrane tension drastically reduces the membrane's overall lifetime.

Conclusions:

• Microplastic adsorption induces mechanical stretching and tension in lipid membranes.
• This physical mechanism provides a potential explanation for microplastic impact on living systems.
• Findings enhance understanding of microplastic interactions with biological membranes.