Indoxyl phosphate

Pneumolysin Sandwich immunoassay with ALP or HRP labelled antibody using 3-indoxyl phosphate (3-IP) as substrate Cyclic voltammetric detection of indigo carmine (Ey 2 =-0.15 V)... 

Voltammetric detection of indigo carmine formed by ALP from 3-indoxyl phosphate... 

P. Fanjul-Bolado, M.B. Gonzalez-Garcia and A. Costa-Garcia, 3-Indoxyl phosphate as an electrochemical substrate for horseradish peroxidase, Electroanalysis, 16 (2003) 988-993. 

C. Fernandez-Sanchez and A. Costa-Garcia, 3-Indoxyl phosphate an alkaline phosphatase substrate for enzyme immunoassays with voltam-metric detection, Electroanalysis, 10 (1998) 249-255. 

Additional substrates include naphthol AS-BI phosphate, naphthol AS-TR phosphate and 5-bromo-4-chloro-3-indoxyl phosphate (BCIP). Other possible chromogens include Fast Red LB, Fast Garnet GBC, Nitro Blue Tetrazolium (NBT) and lodonitrotetrazolium Violet (INT). 

An interesting detection approach combining enzymatic electrochemical detection and silver precipitation is that reported by Martinez-Paredes et al. [40]. They used the enzyme alkaline phosphatase (AP) to catal3 e the dephosphorylation of the substrate 3-indoxyl phosphate thus producing a compound able to reduce silver ions in solution into a metallic deposit localized where the enzymatic label is attached. The deposited silver is then electrochemically stripped into solution and measured by anodic stripping voltammetry (ASV). The DNA hybridization assay was... 

Indoxyl derivatives LC, detection limits using FIA Indoxyl sulfate 2.3 pmol, indoxyl phosphate 3.1 pmol, indoxyl acetate 1.7 pmol, indoxyl 1,3-diacetate 0.4 pmol, indoxyl ) -D-glucoside 0.0015 pmol, indoxyl ) -D-galactoside 0.0015 pmol, indoxyl ) -D-glucuronide 0.0023 pmol, tryptophan 0.25 pmol (201)... 

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