Liposome- or LDL-administered Zn (II)-phthalocyanine as a photodynamic agent for tumours. I. Pharmacokinetic properties and phototherapeutic efficiency.
The pharmacokinetics of Zn-phthalocyanine (Zn-Pc) in mice bearing a transplanted MS-2 fibrosarcoma has been studied using dipalmitoyl-phosphatidylcholine (DPPC) liposomes and low density lipoproteins (LDL) as drug delivery systems. LDL induce a higher Zn-Pc uptake by the tumour and improve the selectivity of tumour targeting as compared to DPPC liposomes. Experimental photodynamic therapy (PDT) of the MS-2 fibrosarcoma has been performed using liposome-delivered Zn-Pc and the efficiency of tumour necrosis has been measured following four different irradiation protocols. We found that Zn-Pc doses as low as 0.07-0.35 mg kg-1 are sufficient for inducing an efficient tumour response that is linearly dependent on the injected dose. The amount of Zn-Pc in the tumour decreases very slowly as a function of time, hence PDT gives satisfactory results even if performed at relatively long time intervals after administration.
Reddi
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E
Department of Biology, University of Padova, Italy.
Zhou
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C
Biolo
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R
Menegaldo
E
E
Jori
G
G
D000818:Animals; D004337:Drug Carriers; D005260:Female; D005354:Fibrosarcoma / Q000188:drug therapy*; D007211:Indoles / Q000008:administration & dosage / Q000493:pharmacokinetics* / Q000627:therapeutic use; D054833:Isoindoles; D008077:Lipoproteins, LDL; D008081:Liposomes; D051379:Mice; D008807:Mice, Inbred BALB C; D009942:Organometallic Compounds / Q000008:administration & dosage / Q000493:pharmacokinetics* / Q000627:therapeutic use; D010778:Photochemotherapy; D015032:Zinc / Q000008:administration & dosage / Q000493:pharmacokinetics* / Q000627:therapeutic use; D017967:Zinc Compounds
D004337:Drug Carriers; D007211:Indoles; D054833:Isoindoles; D008077:Lipoproteins, LDL; D008081:Liposomes; D009942:Organometallic Compounds; D017967:Zinc Compounds; C052159:Zn(II)-phthalocyanine; D015032:Zinc