The 1960 horror film Psycho was shot in black and white. Because Alfred Hitchcock didn't need the fake blood to be red, he found he could get the exact sort of stickiness and opacity he was looking for by using

watered down chocolate syrup. Soon after, filmmakers perfected artificial blood for technicolor,

but 65 years later, scientists are still tinkering with blood substitutes for trauma patients.

From KERA in Dallas, this is Think. I'm Chris Boyd. For now, the best known therapy for someone

who has lost a lot of blood is blood from a human donor. Transfusion procedures have saved

millions of lives. But as my guest will tell us, they've never been a perfect solution,

not least because there isn't always enough donor blood available when and where

it's needed. Nicola Twilly is co-host of the podcast Gastropod and a contributor at The New Yorker,

which published her article The Long Quest for Artificial Blood. Nikki, welcome back to think.

Thanks so much for having me. You open this piece with two simultaneous blood experiments, one on a human man in the UK,

the other on rabbits in Baltimore.

What were the substances being tested on these subjects?

Well, they were both artificial blood in a way, but in different ways.

So I thought of them as like the

impossible burger and the lab phone burger of blood it's a little bit of a

gory idea but one was synthetic blood that does the same thing as as real blood

so that's the impossible burger and then the other was blood that had been

grown in a lab and was being injected into the human man in the UK. So two different approaches

to cracking the same problem. How does one go about growing human blood in a lab outside of a human body?

Yeah, surprisingly difficult, actually, or maybe not that surprising. I don't know. But our bodies

make a lot of this stuff. They're making millions of red blood cells every minute. And yet,

recreating it in a lab turns out to be a really

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