Algin (sodium alginate) ek polysaccharide hai jo brown seaweed se banaya jata hai. Skincare mein iska use thickening, gelling aur film-forming agent ke liye hota hai. Yeh emulsions ko stable rakhta hai aur skin ko hydrating aur smooth texture deta hai. Mostly peel-off masks aur face packs mein use hota hai.