PHOTODYNAMIC INACTIVATION OF HERPES VIRUSES WITH PHTHALOCYANINE DERIVATIVES

The antiviral photosensitization capacity of 11 different phthalocyani ne (Pc) derivatives was examined using herpes simplex virus-1, herpes simplex virus-2 and varicella zoster virus in the search for the most potent sensitizers for viral decontamination of blood. The kinetics of viral photoinactivation were resolved during the stages of viral adso rption and penetration into the host cells. The capacity of Pc in the photodynamic inactivation of viruses was compared with that of merocya nine 540 (MC540), another widely studied photosensitizer. Sensitivity to photoinactivation decreased progressively with time after addition of viruses to their host cells. The viruses were most sensitive to pho todynamic inactivation up to 30 min from the initiation of adsorption. Cell-associated viruses, 45-60 min after the onset of adsorption, are highly resistant to photodynamic treatment by most photosensitizers, with the exception of amphiphilic Pc derivatives. Thus the mixed sulfo nated Pc-naphthalocyanine derivatives AlNSB3P and AlN2SB2P demonstrate d a remarkable decontamination activity even 60 min after the onset of adsorption. Ultrastructural examination of these photosensitized viru ses demonstrated damage to the viral envelope which prevented viral ad sorption and/or penetration. The non-enveloped adenovirus was found to be resistant to all the dyes tested.