Stabilization of RNA Encapsulated in Silk

Area of Science:

• Biomaterials Science
• Molecular Biology
• Biotechnology

Background:

• Ribonucleic acid (RNA), including messenger RNA (mRNA) and microRNA (miRNA), is crucial for diagnostics and therapeutics.
• RNA's inherent instability necessitates stringent, costly storage conditions (e.g., cold temperatures), hindering clinical and research applications.
• Current preservation methods present challenges in terms of cost, logistical complexity, and maintaining RNA integrity.

Purpose of the Study:

• To develop a cost-effective and simplified method for long-term RNA stabilization and transport.
• To investigate the efficacy of silk fibroin matrices in preserving RNA integrity under various storage conditions.
• To overcome the limitations of current RNA storage and handling protocols.

Main Methods:

• Encapsulation of RNA within dried silk fibroin matrices using lyophilization and air-drying techniques.
• Assessment of mRNA stability using real-time quantitative polymerase chain reaction (RT-qPCR) after storage at elevated temperatures (up to 45 °C).
• Evaluation of silk concentration effects on RNA stability and quantification, including the impact on complementary DNA (cDNA) synthesis and resolution using RNA purification kits.

Main Results:

• mRNA samples stored in lyophilized silk matrices demonstrated good stability for up to one week at 45 °C.
• Silk fibroin at concentrations up to 4% w/v did not inhibit RNA quantification after purification, with higher silk concentrations enhancing thermal protection.
• Air-dried silk fibroin matrices with higher silk content provided protection by excluding water, indicating a hydrophobic mechanism for preservation.

Conclusions:

• Silk fibroin matrices offer a promising, simplified approach for the long-term storage and transportation of RNA samples.
• This method enhances RNA stability, particularly at elevated temperatures, by primarily acting through a water exclusion mechanism.
• The findings suggest a potential breakthrough in overcoming logistical and cost barriers associated with RNA preservation for widespread clinical and research use.