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Thin films prepared from protein sources are biodegradable, biocompatible and find application as biomaterials for slow-release drug carriers for skin treatment in burns, ulcers or infected wounds. Cataract eye lenses discarded after surgery have a significant protein content. Films have been prepared from the discarded cataract lens emulsions obtained after surgery. Sorbitol was used as a plasticizer to facilitate film formation that exhibited high water solubility. To enhance the mechanical properties and reduce the solubility of the films, cross-linking of the polypeptide chains was initiated using 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) in presence of NHS (N-hydroxysuccinimide). As the effects of the cross-linker and plasticizer incorporate conflicting properties, an optimization was necessary. The plasticizer imparts flexibility to the film, while the cross-linker decreases solubility but increases hardness that imparts brittleness. A reduction in water solubility of the film for practical applicability was required in such a way that the flexibility was not compromised. The concentration of the cross-linker and the duration of cross-linking were varied to optimize the mechanical properties of the films. The films were characterized using Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), and optical microscopy. Physical properties like thickness and total soluble matter were measured. The mechanical properties of the films were evaluated by performing nano-indentation and nano-tribology (NINT) experiments.