Differentiation of Gram Positive and Gram Negative Bacteria in Transparent Acrylic Resin Emulsion Replicas of Surfaces of Plants

When acrylic resin emulsion (Rohm & Haas Primal AC-33) is allowed to dry on a leaf surface, it can be peeled off to give a transparent replica of the surface with bacteria and fungi embedded in it. The distribution of micro-organisms in the replica appears to reflect the patterns in which they occur naturally on the surface. The resin replicas may be stained by a variety of microscopical stains, the best of which is phenol-acetic-aniline blue, and are suitable for high power light microscopy.
Acrylic resin emulsion differs from widely used cellulose-based materials in that permanent differentiated preparations of Gram positive and Gram negative stained bacteria may be produced from a wide variety of types of surface.