Microrobots Made from Algae Tested for Lung Disease Treatment

Breathing in tiny microrobots that carry medicine may seem like something out of a sci-fi novel, but researchers at UC San Diego are exploring a method to introduce microscopic algae into the lungs for disease treatment right at the source. According to a press release from UC San Diego, our lungs are constantly under threat from outside invaders—think viruses, bacteria, and pollutants. They are also shielded by various barriers like the small hairs in our noses that filter air, mucus and cilia in our windpipes that trap particles, and macrophages in our lungs that work tirelessly to eliminate unknown substances. Due to these defenses, medications for conditions such as pneumonia usually have to be administered through the bloodstream, which often requires higher dosages that can lead to more side effects.

A team led by Joseph Wang and Liangfang Zhang at the Jacobs School of Engineering has started testing the use of microrobots made from green algae to bypass these protective mechanisms. The selection of algae instead of metallic materials is based on their compatibility; they are flexible and don’t provoke intense immune responses. These algae “robots” are infused with medications like antibiotics and then aerosolized into tiny particles that can penetrate the nose and throat barriers to reach the lungs. The innovative aspect here is that the drug-laden microrobots are coated with membranes taken from normal cells, which helps them avoid detection by immune cells, allowing the treatment to distribute evenly within the lungs and take effect before being removed.

In their study published in Nature Communications, the researchers note, “Post nebulization, the microrobots retain their motility to help achieve a homogeneous lung distribution and long-term retention exceeding five days in the lungs.” Tests conducted on mice infected with MRSA showed favorable results; every mouse receiving the microrobot pneumonia treatment survived, while none of those undergoing conventional treatment or receiving no treatment did. Additionally, this technology has been utilized to deliver chemotherapy drugs to mice with metastatic lung tumors. The researchers suggest that human trials could be on the horizon.