Silicon is a chemical element (Si), which can be found on the Periodic Table.

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The main element is a chemical called tetrahydrocannabinol (THC).

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This knowledge is needed to design a chemical that looks enough like the relevant spike element to prompt the immune system to make antibodies that will neutralise it.

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The element to be purified is first incorporated into a chemical that can be turned into a gas. (In this case, the exact compound is still proprietary information.) Then an infra-red laser is shone through the gas.

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