One of the complications when it comes to treating serious diseases like cancer that involves harsh medications like chemotherapy is that the medicines have to circulate through the entire body, causing more side effects. Medical personnel have long looked for ways to deliver harsh treatments like chemotherapy directly to the affected cells in specific areas of the body. Researchers from Caltech’s Division of Engineering and Applied Science believe they have a novel way that could allow the targeted delivery of medications inside the body.
The researchers have developed microbots that can deliver drugs to specific areas of the body. While these microbots could deliver drugs to specific parts of the body, they can be controlled and monitored from outside the body. The microbots are microscopic spheres of magnesium metal that are coated with thin layers of gold and perylene. The latter is a polymer that resists digestion.
The coating layers leave a circular proportion of the sphere uncovered to allow the magnesium to react with fluids in the digestive tract and generate small bubbles. The stream of bubbles produced acts like a jet and propels the sphere forward until hit hits tissue.
A layer of medication is sandwiched between an individual microsphere and the parylene coating. For additional protection in the stomach, the spheres are also coated in microcapsules made of paraffin wax. The spheres are capable of delivering drugs in that configuration but are unable to get to the desired location inside the body.
To guide the microbots to the correct part of the body, the team used photoacoustic computed tomography or PACT. That technique uses pulses of infrared laser light and was developed by researchers on the project. When the microbots are in the vicinity of the tumor, the infrared laser beam briefly heats the microbots, melting the wax capsule, exposing them to stomach acids, and deploying their medication. The scientists say some of the microbots will stick to the location where the medicine is needed and some won’t.