Nonoxynol

Nonoxynol-9 is the most commonly encountered spermatocide in the United States. As with other spermatocides, it destroys spermatozoa; it kills sperm. The nonoxynols, technically speaking, are nonionic surfactant [surface active] mixtures that vary in the number of repeating ethoxy groups. They are much used as detergents, emulsifiers, wetting and defoaming agents, etc. Nonoxynol-9 has 9 repeating ethoxy groups. It is the active component of most vaginal foams and creams.

* * *

non·ox·y·nol (non-okґsĭ-nol) nonylphenoxypolyethoxyethanol. Any of a group of compounds of the general composition C₁₅H₂₄O(C₂H₄ O)_n, which are assigned numbers according to the approximate value of n: nonoxynol 4 is C₁₅H₂₄O(C₂H₄O)₄, or C₂₃H₄₀O₅; nonoxynol 9 is C₃₃H₆₀O₁₀; nonoxynol 15 is C₄₅H₈₄O₁₆; nonoxynol 30 is C₇₅H₁₄₄O₃₁. Nonoxynol 4, 15, and 30 are nonionic surfactants, and nonoxynol 9 is used as a spermicide. Nonoxynol 10, in which n varies from 6 to 16, is used as a pharmaceutical surfactant.