3-Aminophenyl phosphate

The hydrolysis of phosphates is discussed in reviews of nucleophile10 and secondary6 isotope effects. The kinetics and mechanism of the acid hydrolysis of 3-aminophenyl phosphate were studied in 0.1-0.6 m HC1 at 90 °C.55... 

R.M. Pemberton, J.P Hart, P Stoddard, and J.A. Foulkes, A comparison of 1-naphthyl phosphate and 4 aminophenyl phosphate as enzyme substrates for use with a screen-printed amperometric immunosensor for progesterone in cows milk. Biosens. Bioelectron. 14, 495-503 (1999). 

E.J. Moore, M. Pravda, M.P Kreuzer, and G.G. Guilbault, Comparative study of 4-aminophenyl phosphate and ascorbic acid 2-phosphate, as substrates for alkaline phosphatase based amperometric immunosensor. Anal. Lett. 36, 303-315 (2003). 

T.T. Hua, C.E. Lunte, H.B. Halsall and W.H. Heineman, p-Aminophenyl phosphate An improved substrate for electrochemical enzyme immunoassay, Anal. Chim. Acta, 214 (1988) 187-195. 

Substrate p-aminophenyl phosphate and reduction of Ag+ to Ag. Oxidation peak of Ag 100 aM [14]... 

The specific electrochemical behaviour of IDAs is result of its design [97], i.e. two arrays intercalated and individually addressed in a bipotentiostatic system where reversible redox species can be cycled between one array (generator) and the other array (collector) (Fig. 32.3). The feedback obtained, greatly enhances the current and high sensitive detection can be achieved. An important application of IDAs is the electrochemical detection of p-aminophenol when it is generated from p-aminophenyl phosphate, by enzymatic reaction with alkaline phosphatase (like enzymatic label), in geno- [98-100] and immunoassays [101-103]. Another interesting feature of IDAs is the possibility of... 

Streptavidin coupled with phosphatase alkaline (Biospa, Milano, Italy) p-aminophenyl phosphate (PAPP, Universal Sensors, Kinsale-Sandycove, Ireland) 2-(methylamino)ethanol (Aldrich, Milwaukee, USA) bovine serum albumin (BSA), phosphate and tris buffer (Sigma, St Louis, USA). 

Substrate incubation place 15 pL of enzyme substrate solution (10 mM p-aminophenyl phosphate (PAPP) in 100 mM 2-MAE + 2 mM MgCl2 buffer at pH 9) in the Immuchip reservoirs. 

Alkaline phosphatase is one of the most suitable enzymes for electrochemical immunoassays owing to its high turnover number and broad substrate specificity. Different substrates have been used, but 4-aminophenyl phosphate is most suitable, since the reaction product, 4-aminophenol is easily oxidized without fouling of the electrode surface. Thyroxine-binding globulin, cortisol, and prostatic acid phosphatase have been detected by using alkaline phosphatase. 

Figure 14. Cyclic voltammogram of enzyme-linked electrodes in a solution of 0.5 mM p-aminophenyl phosphate ( p-APP) scan rate of 50 mV/s in the case of hybridization with (a) 1 pM complementary target (Tl), (b) 1 uM single base- mismatched target (T3), (c) 1 pM non-complementary target (T2),and (d) without hybridization with target and detection probe (Adapted from Ref.[ 160]).

Tang, H.T., Lunte, C.E., Halsall, H.B., and Heineman, W.R. (1988) p-Aminophenyl phosphate an improved substrate for electrochemical enzyme immunoassay. Analytica Chimica Acta, 214,187-195. 

DA Palmer, et al. Flow injection electrochemical enzyme immunoassay for theophylline using a protein-A immunoreactor and /t-aminophenyl phosphate// -aminophenol as the detection system. Analyst 117 1679, 1992. 

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