Researchers Develop Algae-Based Microrobots for Targeted Medical Delivery

Biomedical engineers at the University of California, San Diego are developing microrobots that combine living algae with synthetic nanoparticles to move through the body and deliver medicine. The devices use the natural swimming motion of Chlamydomonas reinhardtii algae, which can be directed with blue light and dispersed with red light.

Joseph Wang and Liangfang Zhang led the project, attaching drug-carrying nanoparticles to the algae membranes through electrostatic force. In laboratory tests, the researchers formed the algae into shapes such as circles and squares by projecting light through patterned screens.

The same method is being studied for stomach applications using acid-resistant algae collected from mining sites. Researchers are also testing algae-based microrobots to absorb or neutralize toxins in rivers and oceans by coating them with reactive chemicals.

Other groups are examining fully synthetic microrobots for removing plastic waste from marine environments. The work replaces earlier concepts of tiny mechanical devices with systems that rely on biological propulsion. >"Algae just swims and swims.