Investigation of some antimicrobial procedures on the in vitro development of early murine embryos aimed toward developing methods for the disinfection of mammalian embryos prior to transfer.

Eight-cell, zona pellucida-intact mouse embryos were exposed to the following substances or procedures that have been reported to have germicidal effects to determine if the embryos would survive and develop under in vitro conditions: the photosensitive substances hematoporphyrin, hematoporphyrin derivative, 8-methoxypsoralen, 4,5',8-trimethylpsoralen, and thiopyronine; the enzymes lipase (0.5%), phospholipase C (2 U/ml), chymotrypsin (0.5%), and trypsin (0.5%); pH 5.0; and helium/neon laser light, visible light, ultraviolet A light, and ultraviolet C light. Under the conditions used, embryos were not adversely affected by hematoporphyrin and/or helium/neon laser light; methoxypsoralen and/or ultraviolet A light; lipase; trypsin; pH 5.0 for 20 min; and visible light. Variable results were obtained from hematoporphyrin derivative with laser light. Thiopyronine, trimethylpsoralen in combination with ultraviolet A light, and ultraviolet C light killed embryos, and chymotrypsin and phospholipase C were harmful at 10- and 15-min exposure times, respectively.