Abstract: A fuel cell, having improved sealing against leakage, includes a sealant disposed over the peripheral portions a membrane electrode assembly such that the cured sealant penetrates a gas diffusion layer of the membrane electrode assembly. The sealant is applied through liquid injection molding techniques to form cured sealant composition at the peripheral portions of the membrane electrode assembly. The sealant may be thermally cured at low temperatures, for example 130° C. or less, or may be cured at room temperature through the application of actinic radiation. The sealant may be a one-part or a two-part sealant. The sealant includes a polymerizable material, such as a polymerizable monomer, oligomer, telechelic polymer, functional polymer and combinations thereof functionalized with a group selected from epoxy, allyl, vinyl, (meth)acrylate, imide, amide, urethane and combinations thereof.