Medical and Nonmedical Applications of Synthetic Transmembrane Anion Transporters

The transport of anionic species across phospholipid bilayers is an important biological function that plays a vital role in cellular and organismal homeostasis. The function is normally performed by transmembrane transport proteins, but several diseases have been linked to malfunctioning or malregulation of these proteins (so-called "channelopathies"). As a consequence, supramolecular chemists have tried to develop synthetic molecules that can transport anions across biological membranes. While the original goal of this endeavor was the development of potential therapeutics for channelopathies, it is now clear that there are several other potential medical and nonmedical applications for synthetic transmembrane anion transporters. The medical applications of synthetic anion transporters have been widely explored, especially their potential as anticancer agents. However, there are many other applications of synthetic anion transporters that are often overlooked. These range from antibacterial activity and drug delivery, to nonmedical applications such as biomimicry, the development of optical sensors, catalysis, organic synthesis and others. In this review, we aim to highlight the versatility of synthetic transmembrane anion transporters and to convince chemists to look beyond channelopathies and anticancer activity as applications of artificial anion transporters.