Trapezoidal integration approximation was used to find the area under the curve for each mouse, and the log of the integrated mean radiance, which represents the total luciferase expression was used to compare each group's luciferase expression (Figure ). Notably, mRPZ, which contains the same amount of PEI, significantly outperforms PEI N/P=9.3 over ten-fold. However, JetRNA significantly outperforms mRPZ by about three-fold in total expression. PEI N/P=9.3 did express luciferase, as seen in Figure , but luciferase expression was not statically different from the background of the PBS mice. This holds even when controlling for sex (Figure ). When controlling for sex, both mRPZ and JetRNA demonstrate significantly more expression in female mice compared to male mice. Smaller doses of mRPZ, 6 µg per mouse, interestingly yielded total luciferase expression levels that were not statistically different from the 12-µg dose (Figure ). Figure . Firefly luciferase-expressing mRNA was encapsulated using our encapsulation for mRPZ and delivered to Balb/C mice intravenously. Luciferase expression was measured by luminescence resulting from intraperitoneal luciferin injection (A). The luciferase expression kinetics were measured over 96 hours (B) and the integrated luciferase activity, which represents luciferase expression was calculated (C). Live images of the luciferase activity were taken at 18 hours, in the maximum mRPZ expression time window (D).