Nanosized Drug Delivery Vectors and the Reticuloendothelial System

Abstract

Nanomaterials have potential as drug delivery vectors that can improve the chemical stability and pharmacokinetic profile of small molecule drugs or improve drug uptake into solid tumours. However, one consequence of the use of nanosized drug delivery vectors is their potential recognition by tissue macrophages and accumulation in organs of the reticuloendothelial system (RES). While in some instances the uptake of drug loaded nanomaterials or 'nanomedicines' into organs of the RES is favoured, in most instances uptake into the RES can limit systemic exposure of the nanomedicine and limit therapeutic utility. Hence, this section discusses ways in which the RES uptake of nanomedicines can either be promoted or inhibited. Specifically, the effect of various physicochemical properties and presence or absence of key RES 'recognition ligands' on RES uptake are examined.