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Chemistry beyond the boundaries

What are tears made of?

Abbie-Lou Cox explains the makeup and different types of tears

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Tears are one of the most important secretions in the human body. They are vital to keeping the eyes lubricated, hydrated and healthy, which is why their precise chemical composition is of interest in the medicinal field. Each chemical has a function, and knowing these functions can help doctors to treat eye diseases effectively. The biochemistry of tear film is a perfect example of the body’s chemical mastery.

Broadly, tears are composed of three layers: an outer lipid layer, a middle aqueous layer and an inner mucin layer.

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Chemistry beyond the boundaries

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