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Harnessing interactions of functional nano-compartments to generate larger particle assemblies allows studying diverse biological behaviors based on their population states and can lead to the development of smart materials. Herein, thiol-functionalized polymersome nanoreactors are utilized as responsive organelle-like nano-compartments—with inherent capacity to associate into larger aggregates in response to change in the redox state of their environment—to study the kinetics of cascade reactions and explore functions of their collective under different population states. Two nanoreactor populations, glucose oxidase- and horseradish peroxidase-loaded polymersomes, are prepared, and the results of their cascading upon addition of glucose are investigated. The kinetics of resorufin production in associated polymersomes and non-associated polymersome populations are compared, observing a decreased rate upon association. For the associated populations, faster chemical cascading is found when the two types of nanoreactors are associated in a concerted step, as compared to sequential association. The addition of competing agents such as catalase impacts the communication between non-associated polymersomes, whereas such an effect is less pronounced for the associated ones. Altogether, the results showcase the impact of collective associations on enzymatic cascading between organelle-like nanoreactors.

This thesis focuses on the emergence of novel peptide self-replicators from dynamic combinatorial libraries. Thiol functionalised peptide building blocks, first reported by our group in 2010, form the basis of all chapters. The work performed here has two main objectives: First, to deepen the insights obtainable from self-replicating systems and second, to use peptide building blocks to mimic life-like features such as replication. Alongside this, we developed novel strategies to access novel replicators and to dictate their properties.

Transient structural organization as a result of reversible interactions between individual structures is a significant characteristic of biological systems. Rearrangements of individual cells and cellular populations constantly take place as a result of interaction between different cells ‐ in response to chemical cues. Colloidal systems that operate out‐of‐equilibrium attempt to replicate the dynamic association displayed in biological systems. To probe such dynamic behavior, we present an out‐of‐equilibrium micellar nanosystem, which is able to engage in assembly and disassembly processes. Utilizing reversible disulfide chemistry via simultaneous oxidation and reduction of thiol‐functionalized micelles results in formation of dynamic meso‐structures. Such transient behavior is well‐controlled under non‐equilibrium conditions.

Dynamic and adaptive self-assembly systems are able to sense an external or internal (energy or matter) input and respond via chemical or physical property changes. Nanomaterials that show such transient behavior have received increasing interest in the field of nanomedicine due to improved spatiotemporal control of the nanocarrier function. In this regard, much can be learned from the field of systems chemistry and bottom-up synthetic biology, in which complex and intelligent networks of nanomaterials are designed that show transient behavior and function to advance our understanding of the complexity of living systems. In this Perspective, we highlight the recent advancements in adaptive nanomaterials used for nanomedicine and trends in transient responsive self-assembly systems to envisage how these fields can be integrated for the formation of next-generation adaptive stimuli-responsive nanocarriers in nanomedicine.