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Here's how to make your own bacteria handprint

Bacteria are the original social media: they're what people shared among one another long before likes, favorites, revines or 'grams took away what made viral actually viral. Do you even exist until you give me the flu?

Show the world what you're all about, biologically, by making a custom handprint displaying the bacteria you carry on your hand. Tasha Sturm used her son's handprint to make sure none of his friends ever give him a high-five for the remainder of his lifetime (h/t Colossal):

"Handprint on a large TSA plate from my 8 1/2-year-old son after playing outside."

Source: Sturm/Cabrillo College

The above picture shows various bacteria that grew as a result of the experiment, which Sturm does not detail, outside of her own offhand guesses.

Here's how to make your own bacteria handprint:


  • A large petri dish ($8)
  • Some powdered Tryptic Soy Agar (TSA) ($50 to $100; worth it!)
  • An autoclave (autoclaves start at about $2,000 for new models. I'm not sure if buying a used one is kosher, but if you have access to one used in a doctor's office or nail salon, you'll save some serious cash)
  • A super gentle handprint (you'll need a hand and some patience)

Directions: Create a thick mud with water and TSA powder, and autoclave the mud (which will sterilize it). Cool to 55°F and pour the mud into the petri dish. Gently press your hand in the mud, making sure to catch harder-to-reach-areas, like the sides of your thumbs. Store the covered dish (they usually come with a lid) in a 98° place for 24 to 48 hours, mud side up. Remove it from storage and let it sit at room temperature (about 70 degrees) for three or more days.

Quick note from Sturm: "the plate should be treated as a Biohaz," so make sure to throw it out with your nuclear waste according to your city's waste management pickup schedule.