Drug targeting macromolecular carriers

Albmnin is one of the soluble macromolecular carriers available for drug targeting purposes. With a molecular weight of approximately 67 kDa, it is small in size as compared to other potential carriers. It can be derivatized with molecules that will determine its cell specificity, and with drug molecules. A maximum of about 60 molecules can be coupled to albumin through the e-NHj of the lysine residues. Table 4.1 shows the modified albmnins that have been used for targeting to SECs and KCs. 

The pharmacokinetic properties of macromolecular carrier systems for targeted drug delivery were reviewed by Takakura and Hashida [8]. 

Targeting a drug to its site of action is useful to enhance its effectiveness and reduce toxicity. If accessible this can be achieved by direct local application, e.g. eye drops to treat ophthalmic conditions, inhalers to treat respiratory conditions, but currently strategies such as the development of targeting agents such as monoclonal antibodies or the use of the more permeable nature of tumour capillaries to allow accumulation of macromolecular carriers have also been employed. 

Takakura, Y. and Hashida, M. (1996) Macromolecular carrier systems for targeted drug delivery pharmacokinetic considerations on biodistribution. Pharm. Res., 13, 820-831. 

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