Fibronectin Good Humectant Hydration Fibronectin description Type of protein known as a glycoprotein (protein + carbohydrate) that’s naturally found in the skin. Fibronectin’s deterioration from external factors is an element in skin ageing and wrinkling. As is true for all proteins, regardless of their origin, it’s a good water-binding agent for skin. However, applying it topically doesn’t help the fibronectin in your skin. Related ingredients: Glycoproteins