Abstract The development of polymeric biomaterials for modern pharmaceutical formulations has attracted considerable attention, given the recent trend of advanced pharmaceutical modalities that have increased molecular weight and hydrophobicity. Phospholipid polymers, such as poly2-methacryloyloxyethyl phosphorylcholine (MPC)- co - n -butyl methacrylate (BMA) (PMB) is a promising candidate for use as cytocompatible drug carrier materials. PMB is a bioinspired polymer that mimics the plasma membrane and offers superior biomaterial properties, such as bioinert and antibiofouling characteristics. By adjusting the copolymer composition and molecular weight, water-soluble PMB can be synthesized, resulting in the formation of polymeric lipid nanoaggregates. Water-soluble PMB can stably solubilize poorly water-soluble drugs. Moreover, PMB exhibits bidirectional permeation across the plasma membrane. This polymer lipid nanoaggregate, which diffuses and penetrates through intra- and extracellular spaces, was designed as a “cell shuttle”. This focus review discusses studies of cell shuttles in the context of multipharmaceutical modalities, including the effects of polymer architecture on intracellular internalization, the intracellular delivery of hydrophobic compounds, and the cytosolic delivery of proteins. Finally, the utilities of the phospholipid polymer-based cell shuttle are outlined from the perspective of pharmaceutical sciences.
Yoshizaki et al. (Thu,) studied this question.