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Tamper-Proof Time-Temperature Indicator for Inspecting Ultracold Supply Chain
Lam Tan Hao1,2, Minkyung Lee1, Hyeonyeol Jeon1
1Research Center for Bio-based Chemistry, Korea Research Institute of Chemical Technology (KRICT), Ulsan 44429, Republic of Korea.
Abstract:
In the precarious situation caused by the COVID-19 pandemic, the use of messenger ribonucleic acid (mRNA) vaccines is promising for prevention against the infection. However, this type of vaccine has not been effectively commercialized because it needs to be stored and transported at ultracold conditions. mRNA vaccines exposed to undesired temperatures may not show any visible changes but can deteriorate and cause negative effects. Consumers' demand for vaccine authenticity requires logistics to develop a robust monitoring tool to ensure the integrity of ultracold supply chain from manufacturing until vaccination. Here, we report a time-temperature indicator (TTI) that can detect a relatively small change in temperature within subzero ranges, for example, from -70 to -60 °C, which cannot be achieved by current TTIs operating at room temperature. A dyed noneutectic ethylene glycol/water mixture that melts near the mRNA conservation temperature (-69 °C) diffuses into a white absorbent and leaves a colored trace. In addition, the heterogeneous ice particles in the noneutectic mobile phase can prevent absorption during short-term exposure to room temperature. Therefore, the proposed TTI will not record inevitable "meaningless" short-term exposure to room temperature during the cold supply chain but monitor the "meaningful" relatively long-term exposure above -60 °C. These findings help facilitate the safe distribution of the COVID-19 mRNA vaccines.
Insights
A novel time-temperature indicator (TTI) monitors the cold chain for messenger RNA (mRNA) vaccines. This TTI detects temperature deviations in the ultracold range, ensuring vaccine integrity during transport and storage.
Area of Science:
- Materials Science
- Biotechnology
- Logistics
Background:
- The COVID-19 pandemic highlighted the need for effective messenger RNA (mRNA) vaccines.
- Current cold chain logistics face challenges in maintaining ultracold temperatures required for mRNA vaccine stability.
- Ensuring vaccine authenticity and integrity is critical for public trust and therapeutic efficacy.
Purpose of the Study:
- To develop a robust monitoring tool for the ultracold supply chain of mRNA vaccines.
- To create a time-temperature indicator (TTI) capable of detecting subtle temperature changes in subzero ranges (e.g., -70 to -60 °C).
- To differentiate between "meaningless" short-term temperature fluctuations and "meaningful" prolonged exposure to undesired temperatures.
Main Methods:
- A dyed, noneutectic ethylene glycol/water mixture designed to melt near the mRNA conservation temperature (-69 °C) was utilized.
- The mixture's diffusion into a white absorbent material creates a visible colored trace.
- Heterogeneous ice particles in the mobile phase prevent absorption during brief room temperature exposures, filtering out insignificant temperature excursions.
Main Results:
- The developed TTI can detect small temperature changes within the critical subzero range for mRNA vaccine storage.
- The indicator effectively distinguishes between short-term, inconsequential temperature exposures and longer-term, detrimental excursions above -60 °C.
- The TTI provides a visual, reliable record of temperature integrity throughout the vaccine's cold supply chain.
Conclusions:
- The proposed TTI offers a novel solution for monitoring the ultracold supply chain integrity of mRNA vaccines.
- This technology can help ensure the safety and efficacy of vaccines by preventing deterioration due to temperature mismanagement.
- The findings facilitate the secure and reliable distribution of temperature-sensitive vaccines, including those for COVID-19.
