Enhancing the ROS Sensitivity of a Responsive Supramolecular Hydrogel Using Peroxizyme Catalysis

Hydrogels that can disintegrate upon exposure to reactive oxygen species (ROS) have the potential for targeted drug delivery to tumor cells. In this study, we developed a diphenylalanine (FF) derivative with a thioether phenyl moiety attached to the N-terminus that can form supramolecular hydrogels at neutral and mildly acidic pH. The...

Naked-Eye Thiol Analyte Detection via Self-Propagating, Amplified Reaction Cycle

We present an approach for detecting thiol analytes through a self-propagating amplification cycle that triggers the macroscopic degradation of a hydrogel scaffold. The amplification system consists of an allylic phosphonium salt that upon reaction with the thiol analyte releases a phosphine, which reduces a disulfide to form two thiols,...

Enhancing trigger sensitivity of nanocarriers through organocatalytic oxidant activation

The redox balance in tumor and diseased cells often leads to the production of reactive oxygen species (ROS). Many ROS-responsive materials based on sulfur oxidation have been reported with the goal of achieving controlled delivery at the tumor. However, these materials often lack responsiveness to low ROS concentrations present in the tumor...

Chemical signal regulated injectable coacervate hydrogels

In the quest for stimuli-responsive materials with specific, controllable functions, coacervate hydrogels have become a promising candidate, featuring sensitive responsiveness to environmental signals enabling control over sol-gel transitions. However, conventional coacervation-based materials are regulated by relatively non-specific signals,...

Nucleophile responsive charge-reversing polycations for pDNA transfection

Polycationic carriers promise low cost and scalable gene therapy treatments, however inefficient intracellular unpacking of the genetic cargo has limited transfection efficiency. Charge-reversing polycations, which transition from cationic to neutral or negative charge, can offer targeted intracellular DNA release. We describe a new class of...

Fuel-driven macromolecular coacervation in complex coacervate core micelles

Fuel-driven macromolecular coacervation is an entry into the transient formation of highly charged, responsive material phases. In this work, we used a chemical reaction network (CRN) to drive the coacervation of macromolecular species readily produced using radical polymerisation methods. The CRN enables transient quaternization of tertiary...

Thioanisole ester based logic gate cascade to control ROS-triggered micellar degradation

In certain tumor and diseased tissues, reactive oxygen species (ROS), such as H₂O₂, are produced in higher concentrations than in healthy cells. Drug delivery and release systems that respond selectively to the presence of ROS, while maintaining their stability in “healthy” biological conditions, have great potential as...

Temporally programmed polymer – solvent interactions using a chemical reaction network

Out of equilibrium operation of chemical reaction networks (CRNs) enables artificial materials to autonomously respond to their environment by activation and deactivation of intermolecular interactions. Generally, their activation can be driven by various chemical conversions, yet their deactivation to non-interacting building blocks remains...

Tuneable Control of Organocatalytic Activity through Host–Guest Chemistry

Dynamic regulation of chemical reactivity is important in many complex chemical reaction networks, such as cascade reactions and signal transduction processes. Signal responsive catalysts could play a crucial role in regulating these reaction pathways. Recently, supramolecular encapsulation was reported to regulate the activities of...

Organocatalysis in aqueous media

Even though enzymes are the cornerstones of living systems, it has so far proven difficult to deploy artificial catalysts in a biological setting. Organocatalysts are arguably well-suited artificial catalysts for this purpose because, compared with enzymes and inorganic catalysts, they are simpler, often less toxic and widely accessible. This...