@article {399,
	title = {Studies of a benzoporphyrin derivative with Pluronics},
	journal = {Canadian Journal of Chemistry-Revue Canadienne De Chimie},
	volume = {80},
	number = {10},
	year = {2002},
	note = {ISI Document Delivery No.: 623LCTimes Cited: 14Cited Reference Count: 22},
	month = {Oct},
	pages = {1321-1326},
	type = {Article},
	abstract = {The synthetic route for the benzoporphyrin derivatives produces two regioisomers in equimolar quantities (ring A and B isomers). A derivative of the A-ring product, BPD-MA (benzoporphyrin-derivative monoacid ring A, verteporfin), has recently been approved in North America and Europe for the treatment of age-related macular degeneration. The B-ring isomers, contrary to the A-ring isomers, exhibit high aggregation in many formulations, which results in inadequate drug delivery for clinical uses. To avoid aggregation, a non-ionic surfactant polymer such as a Pluronic - poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) - may be used as a formulation excipient. The triblock polymer investigated here is designated P123 (or poloxamer 403). When used to formulate a monoacid benzoporphyrin B-ring derivative (2), a critical micelle concentration of P123 in water occurred at approximately 0.015 to 0.03\%. The apparent pK(a) of compound 2 was dependent on its concentration in P123, and decreased as the molar ratio (P123:2) increased. High concentrations of P123 and neutral pH were found to be the best conditions to maintain the drug in its monomeric form. Kinetic studies suggest that the aggregate of 2 contains several molecules, and is formed by a catalyzed self-assembly process. Samples with 1 mg mL(-1) of drug, at pH = 7.4, and 4.8\% of Pluronic showed satisfactory capacity to load and keep monomers stable. This formulation has potential PDT applications.},
	keywords = {AGGREGATION, AQUEOUS-SOLUTIONS, block copolymers, BPD, COPOLYMERS, DYNAMICS, formulation, micelles, PHOTODYNAMIC THERAPY, photodynamic therapy (PDT), PHOTOSENSITIZERS, photosensitizing drug, Pluronic, poloxamers, porphyrins, SURFACTANTS, THERMODYNAMICS},
	isbn = {0008-4042},
	url = {<Go to ISI>://000179703700007},
	author = {Hioka, N. and Chowdhary, R. K. and Chansarkar, N. and Delmarre, D. and Sternberg, E. and Dolphin, D.}
}
