SWARMS of magneto-aerotactic bacteria equipped with covalently-bound drug-containing nanoliposomes have been administered into the bloodstream to successfully deliver treatment into hypoxic regions of cancerous tumours.
Magneto-aerotactic bacteria tend to travel along local magnetic field lines and toward areas with low oxygen concentration, which are commonly resistant to standard therapies. These characteristics can be effectively utilised to guide nanorobotic agents through the bloodstream and to accurately target cancerous cells deep inside a tumour.
“These legions of nanorobotic agents were actually composed of more than 100 million flagellated bacteria, and therefore self-propelled, and loaded with drugs that moved by taking the most direct path between the drug’s injection point and the area of the body to cure,” Prof Sylvain Martel, Director of the Nanorobotics Laboratory, Polytechnique de Montréal, Montréal, Canada, explained. This autonomous propelling force was enough to reach and penetrate tumours effectively.
The team administered the bacteria close to the site of colorectal tumours in mice. The movement of the bacteria was determined with the use of a computer-controlled magnetic field, perfectly replicating artificial nanorobots designed for this task. The bacteria were able to detect hypoxic zones, which are created by the substantial consumption of oxygen by proliferative tumour cells, and remain in the area to deliver the drug treatment.
This targeted delivery of a drug avoided jeopardising surrounding organs and tissues. Prof Martel explained: “Chemotherapy, which is so toxic for the entire human body, could make use of these natural nanorobots to move drugs directly to the targeted area, eliminating the harmful side effects while also boosting its therapeutic effectiveness,” explained Prof Martel.
“This innovative use of nanotransporters will have an impact not only on creating more advanced engineering concepts and original intervention methods, but it also throws the door wide open to the synthesis of new vehicles for therapeutic, imaging, and diagnostic agents.”