Epinephrine autoinjectors (EAIs) are important first aid medications for treating anaphylaxis. A 10-fold price increase over the past 12 years and evidence that expired EAIs may still contain significant doses of available epinephrine have motivated interest in the efficacy of expired EAIs as treatments of last resort. Degradation of expired EAIs, which can be caused by improper storage conditions, results in various degrees of discoloration of the epinephrine solution. Previous studies have determined that significant epinephrine remains available in expired EAIs, but these have only considered EAIs that show no discoloration. Here, we investigate the potential for colorimetric estimation of available epinephrine dose based on the degree of discoloration in expired EAIs. The correlation of available epinephrine dose and time since expiration date was poor (r = − 0.37), as determined by an industry standard UHPLC protocol. Visible absorbance of the samples integrated across the range 430-475 nm correlated well with available epinephrine dose (r = − 0.71). This wavelength corresponds to the blue channel of a typical smartphone camera Bayer filter. Smartphone camera images of the EAI solutions in various illumination conditions were analyzed to assign color indices representing the degree of discoloration. Color index of the samples showed similar correlation (|r| > 0.7) with available epinephrine dose as that of visible spectrophotometry. Smartphone imaging colorimetry is proposed as a potential point-of-use epinephrine dose estimator for expired and degraded EAIs.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.