notes

Starts off describing biology as this weird field where our body is the 'base'. In other fields like material science, electrical engineering, or mathematics, the 'base' is the laws of physics, or logic. By the end he'll explain that this 'base' is actually quite useful. He gives three examples:

• synthetic cell receptors: we can genetically engineer receptors to only respond to synthetic (don't naturally occur in the body) chemicals.
• exotic physical sensors: cells can be engineered to have sensing modalities like mechanosensitivity (naturally occurring to a degree, this is why tFUS works), temperature and light sensitive receptors can be installed, and even magnetically sensitive receptors. Magnetism is especially interesting because it has only been working recently, and it could benefit a lot from the existing optogenetic stack (which doesn't currently work that well because light has a hard time getting into the body).
• bio-orthogonal chemistry: we can create better pro-drugs. Pro-drugs are inert compounds that when introduced into the body undergo some rearrangement. Usually the reason why they are rearranged is the reason why you want it at all: if something is metabolized in the liver, it means it's likely to survive the digestive tract. If activation depends on an enzyme in a specific tissue, you get localization for free. Now consider two synthetic chemicals that never occur in the body. One of them can be surgically inserted into a tumor. The other can be attached to a cancer drug and circulated around the body. They'll only react, and release the drug, at the site of the tumor. It's an emerging field, and there are no clearly good results yet, but still cool. Ganguli once told us that if you want to get a sense of what a field is interesting, you should scroll the most recent nobel prize winners. Lo and behold, the 2022 Nobel Prize in Chemistry was awarded jointly for developments in bio-orthogonal chemistry and click chemistry (a related field that focuses on modular chemical reactions).