Biodistribution of a Zn(II) phthalocyanine to plasma lipoproteins.

Using MP as the tracer, we found LDL centered in fraction 5, HDL at fractions 14-15 and albumin at 20-21. When DMF was used to solubilize ZnBPc, density gradient ultracentrifugation indicated localization of the agent to two fractions of buoyant density between HDL and LDL (Fig. 1(b) ). When either CRM or TW80 was used for formulation, more than 90% ofthe ZnBPc was found in the LDL fraction (Fig. l(a)). The sensitivity of the fluorescence detector was increased by a factor of 10 to show the minor degree of binding of ZnBPc to HDL and "heavy" proteins. In an attempt to discover the rationale for this behavior, we examined the 726 nm absorbance of solutions of ZnBPc ~ ZnBPc (CRM)