Publication September 2009, 1

3-(10’-PHENOTHIAZINYL)PROPANE-1-SULFONATE IS A POTENT ENHANCER OF SOYBEAN PEROXIDASE-INDUCED CHEMILUMINESCENCE
 
Abstract
3-(10’-Phenothiazinyl)propane-1-sulfonate (SPTZ) was shown to be a potent enhancer of soybean peroxidase (SbP)-induced chemiluminescence. To the best of our knowledge, SPTZ is the first enhancer of SbP to be discovered. Optimal conditions for SbP-catalyzed oxidation of luminol in the presence of SPTZ were determined. The SbP–SPTZ system showed better sensitivity and a lower detection limit (LDL) with respect to the horseradish peroxidase–4-iodophenol system traditionally used in chemiluminescent enzyme-linked immunosorbent assay (ELISA). The addition of 4-morpholinopyridine (MORP) to the SbP–SPTZ system improved its analytical parameters by decreasing the LDL of SbP to 0.03 pM. These results open up very promising perspectives for using the SbP–SPTZ–MORP system in ultrasensitive immunoassay. Figure:  Effect of SbP concentration on light output from luminol/H2O2 substrates in the absence (a) and presence (b) of 0.75 mM SPTZ under the conditions optimized for HRP and described in Ref. [9].

Figure: Effect of SbP concentration on light output from luminol/H2O2 substrates in the absence (a) and presence (b) of 0.75 mM SPTZ under the conditions optimized for HRP and described in Ref. [9]. Conditions: [luminol] = 1.25 mM, [H2O2] = 2.5 mM, and 100 mM Tris buffer (pH 8.6). CL intensity was recorded 4.5 min after the start of the reaction. Each point represents the mean of triplicates. Vertical bars indicate ± S.D. about the mean conditions: [luminol] = 1.25 mM, [H2O2] = 2.5 mM, and 100 mM Tris buffer (pH 8.6). CL intensity was recorded 4.5 min after the start of the reaction.  Each point represents the mean of triplicates.  Vertical bars indicate ± S.D. about the mean.

 
Link: http://www.sciencedirect.com/science/article/pii/S0003269709003649
Publication Date: September 2009, 1