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Abstract Chemically coated micro/nanoparticles are often used in medicine to enhance drug delivery and increase drug up-take into specific areas of the body. Using a recently discovered spontaneous symmetry breaking propulsion mechanism, we demonstrate that chemically coated microparticles can swim through mucus solution under precise navigation and that certain functionalizations can dynamically change propulsion behavior. For this investigation biotin, Bitotin-PEG3-amine, and biotin chitosan were chemically functionalized onto the surfaces of magnetic microparticles using an avidin–biotin complex. These chemicals were chosen because they are used prolifically in drug delivery applications, with PEG and chitosan having well known mucoadhesive effects. Coated microparticles were then suspended in mucus synthesized from porcine stomach mucins and propelled using rotating magnetic fields. The relationship between different chemical coatings, microparticle velocity, and controllability were thoroughly explored and discussed. Results indicate that the biotinylated surface coatings altered the propulsion behavior of microparticles, with performance differences interlinked to both magnetic field properties and localized mucus properties. Precisely controlled drug carrying microparticles are envisioned to help supplant traditional drug delivery methods and enhance existing medical techniques utilizing micro/nanoparticles.
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This content will become publicly available on October 26, 2026
Harnessing The Therapeutic Potential of Selenium
In recent years, selenium has garnered significant interest in biomedical research, particularly through its integration into bioisosteres, and chemical sensors. Despite these promising developments, selenium remains significantly underutilized as a redox-responsive trigger for drug delivery and prodrug activation. In contrast, sulfur—selenium’s lighter chalcogen counterpart—has been extensively utilized in these contexts, primarily through disulfide-based motifs that exploit sulfur’s well-characterized redox properties and metabolic behavior. Notably, disulfides function exclusively through reductive activation, and no broadly established oxidative triggering mechanism exists using sulfur. While selenium and sulfur share similar oxidation states and fundamental reactivity, selenium exhibits distinct chemical behavior arising primarily from its larger atomic size and higher polarizability. These distinctions give rise to unique reactivity profiles that can be strategically leveraged in the design of next-generation prodrugs, enabling unprecedented levels of reactivity and selectivity not achievable with traditional approaches. Here, we report the development of selenium-based prodrugs that harness this unique reactivity to enable dual responsiveness to both reducing and oxidizing conditions. This work highlights how selenium’s divergent chemical behavior can unlock entirely new and more versatile avenues for controlled drug release and targeted delivery—offering a breakthrough strategy to overcome longstanding limitations of traditional sulfur-based systems.
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- Award ID(s):
- 2143826
- PAR ID:
- 10649098
- Publisher / Repository:
- ACS SERMACS, 2025
- Date Published:
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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