Nanofiber-Based Drug Delivery Platform for Bio/Chem/Medical Applications

Novel nanomaterials are being investigated as hosts for the critical delivery of functional molecules in bio/medical applications. Fiber membranes formed by electrospinning¹ represent a versatile platform for accomplishing the controlled release of drugs and other functional molecules. Electrospun fiber membranes display very high surface area and porosity, which greatly enhances interaction with ambient environments and response to external stimuli, forms complex shapes (in homogenous and multi-layer structures), and can be embedded with various functional agents to be released in a controlled manner. In particular, core-sheath structured nanofibers formed by coaxial electrospinning² provide multiple advanced benefits, including (a) combining two material properties effectively, (b) controlling release kinetics of incorporated functional molecules, (c) protecting incorporated molecules in core from harsh environment. The long-term release of encapsulated drugs with minimal/no initial burst release is a key demonstrated aspect. Important recent directions in this growing field include multi-drug delivery³ for obtaining synergistic therapeutic effects and conditional “on-demand” release. We report on several types of electrospun fiber membranes for diverse biomedical applications ranging from dural repair⁴ to transdermal drug release⁵ to controlled drug release for brain tumor therapy ⁶. Fibers using pH responsive materials can provide various sensing and treatment modalities. For example, multi-phasic pH responsive coaxial fibers have been developed⁷ combining two different pH sensitive Eudragit polymers that dissolve in specific pH conditions and release drug payloads in targeted locations of the GI system. Also, the pH responsive coaxial fibers with self-immolative polymer (SIP) sheath encapsulating the core were demonstrated⁸ to provide triggered release. SIP sheath depolymerizes when the head-molecule is cleaved by specific targets, releasing encapsulated drug molecules in core. Finally, we discuss the potential for ‘on-demand’ release, which could be used to provide triggered delivery of synergistic combinations of multiple drugs/nanoparticles. In summary, we have demonstrated the versatility of the nanofiber platform to deliver multiple drugs in different release kinetic conditions for multiple bio/chem/medical applications.
1. Xue, J.; Wu, T.; Dai, Y.; Xia, Y., Electrospinning and Electrospun Nanofibers: Methods, Materials, and Applications. Chemical Reviews 2019, 119, 5298.
2. Han, D.; Steckl, A. J., Coaxial Electrospinning Formation of Complex Polymer Fibers and their Applications. ChemPlusChem 2019, 84 (10), 1453.
3. Han, D.; Steckl, A. J., Triaxial Electrospun Nanofiber Membranes for Controlled Dual Release of Functional Molecules. ACS Appl. Mater. Interfaces 2013, 5 , 8241.
4. Campbell, B.; Anderson, Z.; Han, D.; Nebor, I.; Forbes, J.; Steckl, A. J., Electrospinning of cyanoacrylate tissue adhesives for human dural repair in endonasal surgery. Journal of Biomedical Materials Research Part B: Applied Biomaterials 2022, 110, 660.
5. Tort, S.; Han, D.; Frantz, E.; Steckl, A. J., Controlled drug release of parylene-coated pramipexole nanofibers for transdermal applications. Surface and Coatings Technology 2021, 409, 126831.
6. Han, D.; Serra, R.; Gorelick, N.; Fatima, U.; Eberhart, C. G.; Brem, H.; Tyler, B.; Steckl, A. J., Multi-layered core-sheath fiber membranes for controlled drug release in the local treatment of brain tumor. Scientific Reports 2019, 9, 17936.
7. Han, D.; Steckl, A. J., Selective pH-Responsive Core–Sheath Nanofiber Membranes for Chem/Bio/Med Applications: Targeted Delivery of Functional Molecules. ACS Appl. Mater. Interfaces 2017, 9, 42653.
8. Han, D.; Yu, X.; Ayres, N.; Steckl, A. J., Stimuli-Responsive Self-Immolative Polymer Nanofiber Membranes Formed by Coaxial Electrospinning. ACS Appl. Mater. Interfaces 2016, 9, 11858.