Substrate of neurotoxic esterase NTE Neuropathy target esterase (not an alpha/beta hydrolase but a patatin fold). In vitro hydrolysis assay contains aminoantipyrine (2.5 mM) and K3Fe(CN)6 (5 mM) as detection reagents. Phenol reacts with aminoantipyrine and K3Fe(CN)6 to form a red/orange product recorded at 510 nm