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A Semi-High-Throughput Adaptation of the NADH-Coupled ATPase Assay for Screening Small Molecule Inhibitors
Published on: August 17, 2019
Functionalization of methyl orange using cationic peptide amphiphile: colorimetric discrimination between ATP and ADP
1Division of Applied Chemistry, Graduate School of Engineering, Sojo University, 4-22-1 Ikeda, Kumamoto 860-0082, Japan.
Abstract:
A solvatochromic and non-fluorescent acid-base indicator, methyl orange (MO) was applied to colorimetric discrimination between adenosine triphosphate (ATP) and the corresponding diphosphate (ADP) at pH 2.0 in the presence of L-glutamic acid-derived cationic peptide amphiphile 1. This method is based on the fact that the amphiphile 1 can prevent MO from protonation even at pH 2.0. No similar colour change was observed when ADP was added instead of ATP under the same conditions. The effect of the molecular structure of several peptide amphiphiles and dyes was also investigated.

