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Short interfering RNA (siRNA) therapeutics have soared in popularity due to their highly selective and potent targeting of faulty genes, providing a non‐palliative approach to address diseases. Despite their potential, effective transfection of siRNA into cells requires the assistance of an accompanying vector. Vectors constructed from non‐viral materials, while offering safer and non‐cytotoxic profiles, often grapple with lackluster loading and delivery efficiencies, necessitating substantial milligram quantities of expensive siRNA to confer the desired downstream effects. We detail the recombinant synthesis of a diverse series of coiled‐coil supercharged protein (CSP) biomaterials systematically designed to investigate the impact of two arginine point mutations (Q39R and N61R) and decahistidine tags on liposomal siRNA delivery. The most efficacious variant, N8, exhibits a twofold increase in its affinity to siRNA and achieves a twofold enhancement in transfection activity with minimal cytotoxicity in vitro. Subsequent analysis unveils the destabilizing effect of the Q39R and N61R supercharging mutations and the incorporation of C‐terminal decahistidine tags on α‐helical secondary structure. Cross‐correlational regression analyses reveal that the amount of helical character in these mutants is key in N8's enhanced siRNA complexation and downstream delivery efficiency.
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This content will become publicly available on February 5, 2026
Multi-functional near-infrared fluorescent polymer dot–siRNA for gene expression regulation
Formation of Pdots and Pdot-siRNA and delivery mechanism to the cell. (A) Synthesis of Pdots and binding with siRNA around the Pdots. (B) Pdot-siRNA nanoplatform undergoes cellular uptake and siRNA delivery to target transcripts.
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- Award ID(s):
- 2304873
- PAR ID:
- 10596971
- Publisher / Repository:
- RSC
- Date Published:
- Journal Name:
- Journal of Materials Chemistry B
- Volume:
- 13
- Issue:
- 6
- ISSN:
- 2050-750X
- Page Range / eLocation ID:
- 2124 to 2139
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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