Plasma sterilization. Methods and mechanisms*
Michel Moisan1,**, Jean Barbeau2, Marie-Charlotte Crevier3, Jacques
Pelletier4, Nicolas Philip1, and Bachir Saoudi1
1Groupe de physique des plasmas, Université
de Montréal, B.P. 6128, Succursale Centre-ville, Montréal
H3C 3J7, Québec, Canada; 2Laboratoire de Microbiologie et d'Immunologie,
Faculté de Médecine Dentaire, Université de Montréal,
C.P. 6128, Succursale Centre-ville, Montréal H3C 3J7, Québec,
Canada; 3Groupe de Recherche en Biomécanique et Biomatériaux
(GRBB), Département de Génie Biomédical, École
Polytechnique de Montréal, C.P. 6079, Succursale Centre-ville,
Montréal H3C 3A7, Québec, Canada; 4Laboratoire d'Électrostatique
et de Matériaux Diélectriques, Centre National de la Recherche
Scientifique et Université Joseph Fourier, B.P. 166, 38042-Grenoble
Cedex 9, France
Abstract: Utilizing a plasma to achieve sterilization is a possible
alternative to conventional sterilization means as far as sterilization
of heat-sensitive materials and innocuity of sterilizing agents are
concerned. A major issue of plasma sterilization is the respective roles
of ultraviolet (UV) photons and reactive species such as atomic and
molecular radicals. At reduced gas pressure (£10 torr) and in mixtures
containing oxygen, the UV photons dominate the inactivation process,
with a significant contribution of oxygen atoms as an erosion agent.
Actually, as erosion of the spore progresses, the number of UV photons
successfully interacting with the genetic material increases. The different
physicochemical processes at play during plasma sterilization are identified
and analyzed, based on the specific characteristics of the spore survival
curves.
* Lecture presented at the 15th International Symposium
on Plasma Chemistry, Orléans, France, 9-13 July 2001. Other presentations
are presented in this issue, pp. 317492.
** Corresponding author.