Abstract Diabetes is one of the most pressing healthcare challenges facing society. Dysfunctional insulin signaling causes diabetes, leading to blood glucose instability and many associated complications. While the administration of exogenous insulin is then essential for achieving glucose control, issues with dosing accuracy and timing remain. Hydrogel‐based drug delivery systems have been broadly explored for controlled protein release, including for applications in long‐lasting and oral insulin delivery. More recently, efforts have focused on injectable hydrogels with glucose‐directed controlled release of insulin and glucagon, aiming for more autonomous and biomimetic approaches to blood glucose control. These materials typically use protein‐based sensing mechanisms or glucose binding by synthetic aryl boronates for glucose‐directed release. Despite advancements in this area, there remains a need for more precise timing of therapeutic availability to afford healthy blood glucose homeostasis, providing an opportunity for further research and innovation. This review summarizes the current state of hydrogel‐based delivery of insulin and glucagon, with insights into the potential benefits, future directions, and challenges that must be overcome to achieve clinical impact. 
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                            Enhanced dynamic covalent chemistry for the controlled release of small molecules and biologics from a nanofibrous peptide hydrogel platform
                        
                    
    
            Abstract Maintaining safe and potent pharmaceutical drug levels is often challenging. Multidomain peptides (MDPs) assemble into supramolecular hydrogels with a well-defined, highly porous nanostructure that makes them attractive for drug delivery, yet their ability to extend release is typically limited by rapid drug diffusion. To overcome this challenge, we developed self-assembling boronate ester release (SABER) MDPs capable of engaging in dynamic covalent bonding with payloads containing boronic acids (BAs). As examples, we demonstrate that SABER hydrogels can prolong the release of five BA-containing small-molecule drugs as well as BA-modified insulin and antibodies. Pharmacokinetic studies revealed that SABER hydrogels extended the therapeutic effect of ganfeborole from days to weeks, preventingMycobacterium tuberculosisgrowth better than repeated oral administration in an infection model. Similarly, SABER hydrogels extended insulin activity, maintaining normoglycemia for six days in diabetic mice after a single injection. These results suggest that SABER hydrogels present broad potential for clinical translation. 
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                            - Award ID(s):
- 2203948
- PAR ID:
- 10549840
- Publisher / Repository:
- bioRxiv
- Date Published:
- Format(s):
- Medium: X
- Institution:
- Rice University
- Sponsoring Org:
- National Science Foundation
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