Porphyrins are heterocyclic organic compounds that can be excited under irradiation with light,
transferring energy collisionally to surrounding biomolecules. Porphyrins can be incorporated
into various solid matrices, such as cellulose acetate membranes (CAMs). Hence, photodynamic
properties of porphyrins may be useful in situations where microbial inactivation is required,
such as during the physical and chemical treatment of drinking water. No work has examined the
efficacy of porphyrin inactivation on human enteric viruses such as hepatitis A virus (HAV) in
water. Experiments were conducted to evaluate the effect of cationic, anionic, and amphiphilic
porphyrins on HAV in porphyrin-containing water or water-containing buffers exposed to long-wavelength
(365 nm) ultraviolet (UV) light. Inactivation of poliovirus type 1 (PV1) and coliphage MS2 also
was determined, and inactivation of the bacterium E. coli B was determined on porphyrin-containing
membranes. Results are expressed as the percent reduction in log10 infectious units at
time (t) when compared to numbers of microbes not exposed to treatment with UV light. When
porphyrin-containing CAMs were exposed to long wavelength UV light, E. coli B was
inactivated by about 90% in 300 minutes. In contrast, reductions of E. coli B in 0.01 mM
cationic or anionic porphyrin solutions ranged from 97.5% after 10 minutes and was >99.999%
after 90 minutes. Percent reductions of MS2 in cationic or anionic porphyrin solutions ranged
from 99.8% to >99.99% after 10 minutes. Poliovirus was inactivated by >99.99% in 1 minute in
0.01 mM cationic or anionic solutions, while reductions of HAV by 0.01 mM cationic porphyrin
in water was 99% in 1 minute and >99.98% in 10 minutes. Amphiphilic porphyrins also resulted
in rapid and extensive (>99.98% in 1 minute) inactivation of HAV in water. Concentrations of
porphyrins that inactivated viruses were minimally toxic to Chinese Hamster Ovary cells and
nonmutagenic in the Ames test. These experiments show that porphyrin-containing water and
membranes can inactivate infectious viruses and bacteria. Includes 31 references, tables, figure.
| Edition : | Vol. - No. |
| File Size : | 1
file
, 320 KB |
| Note : | This product is unavailable in Ukraine, Russia, Belarus |
| Number of Pages : | 14 |
| Published : | 11/02/2003 |
