Intracellular delivery of nucleic acids to mammalian cells using polyplex nanoparticles (NPs) remains a challenge both in vitro and in vivo, with transfections often suffering from variable efficacy. To improve reproducibility and efficacy of transfections in vitro using a next‐generation polyplex transfection material poly(beta‐amino ester)s (PBAEs), the influence of multiple variables in the preparation of these NPs on their transfection efficacy was explored. The results indicate that even though PBAE/pDNA polyplex NPs are formed by the self‐assembly of polyelectrolytes, their transfection is not affected by the manner in which the components are mixed, facilitating self‐assembly in a single step, but timing for self‐assembly of 5–20 min is optimal. In addition, even though the biomaterials are biodegradable in water, their efficacy is not affected by up to eight freeze‐thaw cycles of the polymer. It was found that there is a greater stability of nucleic acid‐complexed polymer as a polyplex nanoparticle compared with free polymer. Finally, by exploring multiple buffer systems, it was identified that utilization of divalent cation magnesium or calcium acetate buffers at pH 5.0 is optimal for transfection using these polymeric materials, boosting transfection several folds compared with monovalent cations. Together, these results can improve the reproducibility and efficacy of PBAE and similar polyplex nanoparticle transfections and improve the robustness of using these biomaterials for bioengineering and biotechnology applications.
Therapeutic proteins are utilized in a variety of clinical applications, but side effects and rapid in vivo clearance still present hurdles. An approach that addresses both drawbacks is protein encapsulation within in a polymeric nanoparticle, which is effective but introduces the additional challenge of destabilizing the nanoparticle shell in clinically relevant locations. This study examined the effects of crosslinking self‐assembled poly(
- PAR ID:
- 10457858
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Biotechnology and Bioengineering
- Volume:
- 117
- Issue:
- 8
- ISSN:
- 0006-3592
- Page Range / eLocation ID:
- p. 2504-2515
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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