Detection of sucrase-isomaltase in stains on a knife by sandwich enzyme immunoassay to determine penetration of the small intestine in a pig model.

Using 2 kitchen knives, 2 stab wounds were made into the abdomen of a pig that had been sacrificed under sanctioned processing methods of a meat packing plant. One knife wound penetrated the jejunum and the other, the liver. After leaving the knives at room temperature for a week, the stains on the blades were extracted and subjected to a sandwich enzyme immunoassay to detect the presence of sucrase-isomaltase (sucrase-alpha-dextrinase or SI), a major digestive enzyme of the small intestine. Results of this assay revealed that sufficient SI could be detected only on the knife that had penetrated the jejunum. This animal experiment thus suggests the potential usefulness of an SI assay to identify a weapon that has penetrated the small intestine. Further investigation will be pursued to determine whether this detection method is also valid in humans.