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bioRxiv · 10.1101/2025.08.06.668851

Multifunctional semiconducting polymer dots as a miRNA delivery system for osteogenic differentiation and stem cell tracking

Song, P.·Kjems, J.
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Abstract

Small interfering RNAs (siRNA) and microRNAs (miRNA) are potent gene regulators through RNA interference (RNAi). In this study, we developed a multifunctional theranostic carrier for small RNA delivery and cell tracking using a polymer based nanoparticle composed of the lipid-like material S14, Pluronic F127 and semiconducting polymer MEH-PPV (SPM-dots). The resulting SPM-dots showed efficient siRNA transfection and labeling of human mesenchymal stem cells (hMSCs). Delivery of miR-29b to hMSCs significantly enhanced osteogenic differentiation. Furthermore, hMSCs transfected with SPM-dots displayed strong fluorescent signals in vivo after subcutaneous transplantation. These findings indicate that SPM-dots hold great potential as carrier for gene delivery and cell tracking applications.

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Song, P., Kjems, J.. 2025-08-07. Multifunctional semiconducting polymer dots as a miRNA delivery system for osteogenic differentiation and stem cell tracking. https://doi.org/10.1101/2025.08.06.668851

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