Biocidal action of PHMB
PHMB action on micro-organisms
A simple description of the mechanism of action of PHMB against bacteria is as follows :
1. PHMB is quickly attracted to the bacteria surface
2. PHMB neutralises the cell wall protection system (called « exclusion system») : it combines with proteins in charge of this defence
3. PHMB passes through the cell wall to join the cytoplasmic membrane
4. PHMB enters in the 1st stage of its action against bacteria (bacteriostatic level : reversible) :
PHMB creates some spaces in the cytoplasmic membrane by association with proteins. This starts up the loss of little size compounds (potassium, calcium…) : membrane is getting permeable
5. PHMB enter in the 2nd stage of its action against bacteria (bactericidal level : not reversible) :
PHMB breaks up the cell cytoplasmic membrane. The cell looses its vital compounds
6. The cell dies
Some efficacy data
These data are given as an information.
One should perform its own tests prior to declare any efficacy data of end use developed products.
| Micro-organisms | Indicative M.I.C. values (ppm) |
| Bacteria | |
| Pseudomonas aeruginosa | 100 (*) |
| Staphylococcus aureus | 1 |
| Streptococcus faecalis | 25 |
| Escherichia coli | 25 |
| Pseudomones putida | 25 |
| Klebsiella aerogenes | 25 |
| Fungii | Indicative M.I.C. values (ppm) |
| Aspergillus niger | 750 |
| Trichophyton mentagrophytes | 25 |
| Yeasts | Indicative M.I.C. values (ppm) |
| Endomycopsis albicans. | 300 |
(*) Decreasing of pseudomonas aeruginosa versus concentrations and contact times :
| Contact times | 5 min. | 15 min. | 30 min. |
| with PHMB at 10 ppm | - 75 % | - 88 % | - 99.999 % |
| Contact times | 30 seconds | 1 min. | 3 min. |
| with PHMB at 50 ppm | - 82 % | - 96 % | - 99.999 % |
