Structure and applications of PIC-based polymers and hydrogels

Abstract

Over the last decade, water-soluble polyisocyanopeptides (PICs) have emerged as a new class of biomimetic polymers. Analogous to biopolymers, PICs exhibit a semi-flexible nature; however, unlike their biological counterparts, they possess the unique advantage of being highly customizable. Hydrogels made of PICs have a fibrous and porous architecture and, consequently, unique mechanical properties. This includes strain stiffening, which is well known in biological materials but rarely found in synthetic gels. These properties make PIC hydrogels uniquely suited for a wide range of biological applications. One key application is their use as a highly tailorable, biomimetic 3D cell culture matrix, which also allows for investigating interactions between cells and their environment. Beyond gel applications, soluble PICs are used in an immunological setting, where they provide a multivalent scaffold for the development of synthetic dendritic cells. This review aims to provide a comprehensive overview of PICs, encompassing their structure, properties, and key applications. First, we discuss the history, synthesis, and characterization methods of PIC hydrogels, followed by an overview of current applications that range from biosensing and immunotherapy to cell culture and wound healing. Presenting these different applications, we demonstrate that these polymers are a multi-versatile scaffold, triggering the interest of material scientists, biologists, chemists, and medical engineers.