The extremely short half-lives, poor chemical stability, and natural degradation of RNAs by nucleases resulted in the development of carrier molecules at the nanoscale for RNA delivery into cells. Nanoparticle-based delivery systems protect RNA molecules from enzymatic degradation and immune system attacks and enable the accumulation of RNA in tumors. In general, nanoparticles range from 10 to 200 nanometers (nm), which enhances their tumor permeability and retention effect.
Currently, nanocarriers employed for RNA delivery are
(i) lipid-based nano-systems,
(ii) polymeric nanomaterials,
(iii) inorganic nanoparticles, or
(iv) Bio-inspired nanovehicles.
Table 1 :
Nanoparticle-based platforms for RNA delivery (Lin et al. 2020).
Nanocarriers | Classifications | Advantages | Disadvantages |
Lipid-based nanostructures | Liposomes; solid lipid nanoparticles; lipid emulsions | Easy preparation, with good biocompatibility and biodegradability. | Limited stability, easy leakage of payloads, and rapid clearance. |
Polymer-based nanomaterials | Natural or naturally derived polymers: chitosan, poly-l-lysine, atelocollagen, etc. | Good biocompatibility and biodegradability for natural or naturally derived polymers, low cost of production, stimulation of drug release, easy modification. | Nondegradable for some responsive polymers, dose-dependent toxicity. |
Inorganic NPs | MSNs, CNTs, QDs, and metal nanoparticles (e.g., iron oxide and gold nanoparticles) | Easy surface modification, good reproducibility, and easy cell uptake. | Non-biodegradability, potential toxicity. |
Bio-inspired nano-vehicles | DNA-based nanostructures, exosome-mimetic nanovesicles, red blood cell member-based ghosts. | Good biodegradability, low toxicity, strong targeting and low immune induction. | High cost, stability concern. |
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ReferenceLin YX, Wang Y, Blake S, Yu M, Mei L, Wang H, Shi J. RNA Nanotechnology-Mediated Cancer Immunotherapy. Theranostics 2020; 10(1):281-299. doi:10.7150/thno.35568. Available from http://www.thno.org/v10p0281.htm
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