This review comprehensively summarizes the application of PEG-functionalized amphiphilic pillararenes in drug delivery systems for chemotherapy, phototherapy, and gas therapy of tumor. Some corresponding examples were discussed in detail to evaluate their performance in chemotherapy, phototherapy, and gas therapy of tumor. At the end, some future developmental directions for PEG-functionalized amphiphilic pillararenes were also put forward.

Abstract

As a new generation of supramolecular host macrocyclic molecules, pillararenes display many advantages including simple synthesis routes, rigid electron-rich structures, unique host-guest interactions, and adjustable cavity sizes, which make them widely be used in drug delivery systems for precise diagnosis and treatment of cancer. The molecular functions of pillararenes can be easily expanded through the introduction of different functional groups into the side chain. For example, polyethylene glycol (PEG) which has good biocompatibility and water solubility can be used to construct PEG-functionalized amphiphilic pillararenes. These PEG-functionalized amphiphilic pillararenes can be used to construct the nanocarriers with good water solubility and excellent biocompatibility through their self-assembly to deliver hydrophobic drugs. Although there are many reviews introducing the application of amphiphilic pillararenes in drug delivery, there are still no comprehensive articles summarizing such type of pillararenes. In this paper, based on their functional characteristics, the applications of PEG-functionalized amphiphilic pillararene in drug delivery systems have been summarized. We focused on the relationship between their molecular design and functional application, providing reasonable guidance for the structural design of amphiphilic pillararenes.