The invention relates to highly biocompatible or biophilic un-cross-linked or cross-linked polymers comprising one or more side-chain active acrylic amino acids of formula I wherein: X is —NH(CH2)4—, —O—C6H4—CH2—, —OCH2—, —O—CH(CH3)—, —S—CH2—, —O-proline, and R is H or CH3; and wherein the polymer further includes a free radical initiator and, optionally, a cross-linking agent having a plurality of polymerizable ethylenically unsaturated groups. The invention further concerns various highly biocompatible, cross-linked co-polymers comprising one or more monomers of formula I, and one or more other polymerizable monomers. Uses of such polymers and co-polymers for the production of contact lenses, intraocular lenses, implants, wound healing slabs, additives for food and cosmetics, conductive plastics, spinnable fibers, and the like are disclosed.