Atmospheric methane levels increased over geological formations in Northern Siberia following a heat wave in 2020, suggesting that permafrost thaw releases methane from reservoirs.
Image credit: Wikimedia Commons.
Edited by David A. Weitz, Harvard University, Cambridge, MA, and approved March 7, 2017 (received for review November 14, 2016)
Significance
A nonfluorescence-based technology is introduced that can lead to visual detection of enzyme activity. These results represent a dramatically different paradigm for creating sensors based on dynamic liquid lenses with general utility.
Abstract
In this paper, we describe an approach to measuring enzyme activity based on the reconfiguration of complex emulsions. Changes in the morphology of these complex emulsions, driven by enzyme-responsive surfactants, modulate the transmission of light through a sample. Through this method we demonstrate how simple photodetector measurements may be used to monitor enzyme kinetics. This approach is validated by quantitative measurements of enzyme activity for three different classes of enzymes (amylase, lipase, and sulfatase), relying on two distinct mechanisms for coupling droplet morphology to enzyme activity (host–guest interactions with uncaging and molecular cleavage).
Footnotes
↵1Present address: Department of Materials Science and Engineering and Department of Chemistry, The Pennsylvania State University, University Park, PA 16802.
↵2Present address: Department of Chemistry, Northwestern University, Evanston, IL 60208.
↵3Present address: Department of Chemical Engineering, Tianjin University, Tianjin 300072, People's Republic of China.
- ↵4To whom correspondence should be addressed. Email: tswager{at}mit.edu.
Author contributions: L.D.Z., J.A.K., and T.M.S. designed research; L.D.Z., J.A.K., X.H., and J.J.W. performed research; L.D.Z., J.A.K., and T.M.S. analyzed data; and L.D.Z., J.A.K., and T.M.S. wrote the paper.
The authors declare no conflict of interest.
This article is a PNAS Direct Submission.
This article contains supporting information online at www.pnas.org/lookup/suppl/doi:10.1073/pnas.1618807114/-/DCSupplemental.
Enzyme activity using dynamic droplet lenses
Article Classifications
- Physical Sciences
- Applied Physical Sciences
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