Poly elcoat provides a water-based coating formulation called Poly elcoat that uses gelatin, which has traditionally been difficult to use in film coatings. A representative patent for using gelatin in coatings is US Patent No. 6,077,540, which discloses a gelatin spray coating method developed by Daher et al. The document also references a one micron photomicrograph showing gelatin micro and nanoparticles.