Hyaluronic Acid Serum 1 fl oz (30 ml) Liquid by Swanson Premium. $6.99. Swanson Hyaluronic Acid Serum. 99% natural and paraben free. Helps soften and soothe your skin. Take care of your skin with Hyaluronic Acid (HA) Serum from Swanson! This special serum softens and soothes your skin, helping you maintain a beautiful, youthful glow. It contains 3% sodium hyaluronate, the active ingredient in this wonderful formula.