UV-Resistant Cell-Free Reactions with Synthetic Melanin Additives

Escherichia coli lysate-based
cell-free
systems have gained traction for a variety of point-of-use biological
applications. Lysate-based cell-free reactions can be freeze-dried,
deployed without requiring cold chain, and have a high ease of use
through simple rehydration. To maximize their potential, it is of
interest to stabilize these reactions to withstand a variety of conditions
for long-term storage and use, including stabilization to UV exposure.
To address this issue and aid in point-of-use applications, we investigate
the use of synthetic melanin nanoparticles as UV-protective additives
that are compatible with cell-free reactions. These particles have
broadband absorption properties and radical scavenging activity that
allow for protection from free radical generation during prolonged
UV exposure. Stabilizing cell-free reactions in this way may prolong
the stability for use in the field where exposure to sunlight is inevitable.