5 kDa Hyaluronic Acid (HA) NA Sodium Hyaluronate Spray 1 fl oz - Lori G Ashley®. The most effective hyaluronic acid is the one with the lowest molecular weight which penetrates deeper into the skin. The deeper Hyaluronic acid goes into the skin, the better the results. 5 kDa Hyaluronic Acid (HA) NA Sodium Hyaluronate stores water in the connective tissue of the skin and provides intense moisturization. Its long-lasting hydration makes the skin plumper & smoother, reduces the visible signs of ageing and promotes firmer skin with improved skin elasticity.