Stabilization of vaccines and antibiotics in silk and eliminating the cold chain.

Tufts University, Department of Biomedical Engineering, Medford, MA 02155, USA.
Proceedings of the National Academy of Sciences (Impact Factor: 9.81). 07/2012; 109(30):11981-6. DOI: 10.1073/pnas.1206210109
Source: PubMed

ABSTRACT Sensitive biological compounds, such as vaccines and antibiotics, traditionally require a time-dependent "cold chain" to maximize therapeutic activity. This flawed process results in billions of dollars worth of viable drug loss during shipping and storage, and severely limits distribution to developing nations with limited infrastructure. To address these major limitations, we demonstrate self-standing silk protein biomaterial matrices capable of stabilizing labile vaccines and antibiotics, even at temperatures up to 60 °C over more than 6 months. Initial insight into the mechanistic basis for these findings is provided. Importantly, these findings suggest a transformative approach to the cold chain to revolutionize the way many labile therapeutic drugs are stored and utilized throughout the world.

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