Preclinical Study Of New Anti-tumor Drug Of Magnetic Albumin Microspheres Combining MTX

A new anti-tumor drug, FM-MTX, a kind of microspheres suspension, was prepared by combining ferromagnetic ultramicrodots fluids with methotrexate (MTX) linking to human serum albumin (HSA). With the magnetic material (ultrafine particles of magnetite, Fe₃O₄) in the microspheres, it is susceptible to magnetic field. It is of magnetic response and can be directed to the specific target, meanwhile preserving its cytotoxicities of the antitumor drug MTX. Therefore, the drug delivery system theoretically would have many advantages. First of all, it could concentrate the most of drugs at the tumor site via fixing external magnetic field at the area. Then, it needs only small doses of agents for the therapic effects with minimal toxicity of drugs for the body.In this study, the magnetic methotrexate albumin conjugate FM-MTX was prepared. The pharmaceutic charecteristics and parameters were investigated. The cytoxicities in vitro , anti-tumor effects in vivo, and the toxicity and pharmacokinetic distribution in vivo were evaluated.Preparation of FM-MTXSeveral factors must be taken into consideration in choosing proper methods for production of FM-MTX conjugates. First of all, the conjugates should well preserve the pharmacological activities. Second, the coupling of drug carrying intermediaries should avoid formation of homopolymer or aggregates. Third, the linkage should be stable enough to allow the conjugated agents to reach to tumor site without being dissociated. Finally, the linkage in the conjugates must release the conjugated drug in the tumor site. Based on the...