New enhancers for the chemiluminescent peroxidase catalysed chemiluminescent oxidation of pyrogallol and purpurogallin.
The effects of various boronate compounds, 4-biphenylboronic acid, 4-bromobenzene-boronic acid, trans-4-(3-propionic acid)phenylboronic acid and 4-iodophenylboronic acid, on the horseradish peroxidase (HRP) catalysed chemiluminescent oxidation of pyrogallol and purpurogallin by peroxide were investigated. trans-4-(3-Propionic acid)phenylboronic acid produced a 13.7-fold enhancement in the peak light emission from the chemiluminescent HRP catalysed pyrogallol reaction (detection limit for HRP < 1.25 fmol). At low enhancer concentration a single peak of light emission was observed and as the enhancer concentration increased the time to peak light emission became progressively longer. The chemiluminescence showed two peaks at higher concentrations (> 54.3 mumol/L) and the individual peak times depended upon the concentration of the enhancer. All of the boronates enhanced peak light emission in the chemiluminescent HRP catalysed purpurogallin reaction. 4-Biphenylboronic acid was the most effective and it enhanced peak light emission 314-fold. The practical detection limit for HRP (Type VIA) using this enhancer was 4.18 pmol (peak emission at 20 minutes). This compound also enhanced peak light emission 232-fold from a chemiluminescent HRP-purpurogallin reaction in which molecular oxygen replaced peroxide as the oxidant.
Nozaki
O
O
Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia 9104-4283, USA.
Ji
X
X
Kricka
L J
LJ
D000975:Antioxidants / Q000737:chemistry*; D001567:Benzocycloheptenes / Q000737:chemistry*; D001897:Boronic Acids; D002384:Catalysis; D006735:Horseradish Peroxidase / Q000378:metabolism*; D008163:Luminescent Measurements; D010084:Oxidation-Reduction; D011748:Pyrogallol / Q000737:chemistry*; D012680:Sensitivity and Specificity; D013329:Structure-Activity Relationship
D000975:Antioxidants; D001567:Benzocycloheptenes; D001897:Boronic Acids; D011748:Pyrogallol; D006735:Horseradish Peroxidase; C026133:purpurogallin