Modes of action of disinfectants.

The exact mechanism of action of a disinfectant is not easy to elucidate. The notion of 'target' in the bacterial cell, frequently evoked for the antibiotics, is not clear for disinfectants (except for some, e.g. chlorhexidine). In understanding the mode of action of a disinfectant, it can be difficult to distinguish the primary stage (characteristic of the mode of action) and the secondary stage (consequence of the action). The author describes the actions of disinfectants on the external membrane, cytoplasmic membrane and energy metabolism of cells; these actions include rupture of the membrane, loss of permeability and coagulation of the cytoplasm.