الفهرس 
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Abstract
Photodynamic therapy (PDT), is a promising novel therapeutic method for the treatment of many tumors. It utilizes a photosensitizer (PS),appropriate wavelength for photoexcitation and oxygen to produce singlet oxygen and other reactive oxygen species leading to lipid peroxidation photo-oxidation of DNA guanine, damage to membranes, cytoskeletons and other sites, and eventual cell death (Moan and Berg, 1992; Henderson and Dougherty,1992 The first and still frequently clinically approved photosensitizer is hematoporphyrin derivative (HpD) and photofrin, which has, however,several drawbacks. Firstly, its longest wavelength absorption maximum isaround 630 nm, where the penetration depth of light in soft tissues is quitesmall. Secondly, it is not a pure compound but a mixture of porphyrin dimers and oligomers. Finally, it causes prolonged skin photosensitivity aftertreatment. Since the photosensitizer is a key element in PDT, there has been continuous active search for identifying new photosensitizers which can optimize the tumor response to PDT and minimize the side effects and limitations which were met with HPD and photophrin (Dougherty et al 1998). Zinc (II) phthalocyanine is one of the second generation photosensitizers which besides the chemical purity and high singlet oxygen quantum yield, its absorption Q bands are at longer wavelength (around 670nm) were maximum penetration of light into tissues is attained.