Compositions of saltwater-stable adhesive hydrogels are provided, as well as methods of use thereof in adhesion, drug delivery, antibiotic delivery, surface coating, and antifouling applications. Disclosed copolymer complexes exhibit reversible ionic strength-based solubility between a soluble complex and an insoluble hydrogel, and include a first polynorbornene (PNB)-based bottlebrush copolymer including a plurality of -cyclodextrin (-CD)-terminated oligoethylene glycol sidechains and a second PNB-based bottlebrush copolymer including a plurality of positively charged adamantane (Ad)-terminated oligoviologen sidechains. In some embodiments, the second PNB-based bottlebrush copolymer further includes at least one porphyrin-terminated sidechain and/or has at least one electrostatically loaded, negatively charged therapeutic drug.

An (acid-substituted polyaniline)-grafted hydrogel copolymer is provided. The (acid-substituted polyaniline)-grafted hydrogel copolymer has a general formula as below: ##STR00001##
wherein A is a proton acid group, m and n are same or different integers greater than 0, x is an integer equal to or greater than 0, and y is an integer equal to or greater than 1, provided that x and y are the same or different at each occurrence, and at least an x is not 0. The (acid-substituted polyaniline)-grafted hydrogel copolymer is formed by the polymerization and substitution reaction between chitosan, polyaniline, and proton acid. The (acid-substituted polyaniline)-grafted hydrogel copolymer behaves as a pH-responsive hydrogel with photo-thermal properties and can be applied to photo-thermal therapy.

A packaging system for the storage of an unused contact lens includes a sealed plastic package that contains an unused, contact lens in a buffered saline solution and is sterilized, wherein the contact lens comprises a polymerization product of a contact lens-forming mixture comprising (a) one or more grafted glycosaminoglycan polymers comprising a glycosaminoglycan having a polymer backbone and one or more side chains comprising an ethylenically unsaturated reactive-containing residue grafted onto the polymer backbone, and (b) one or more non-silicone contact lens-forming monomers, wherein the contact lens has an equilibrium water content of at least about 80 wt. %.