Hf. Zhou et al., Imaging localized horseradish peroxidase on a glass surface with scanning electrochemical/chemiluminescence microscopy, ANALYT BIOC, 290(1), 2001, pp. 83-88
Scanning electrochemical/chemiluminescence microscopy (SECM/SCLM) was devel
oped for simultaneous imaging of chemiluminescence and topography of immobi
lized horseradish peroxidase (HRP) on a glass substrate. When the SECM tip
for electrochemical generation of H2O2 scanned over the immobilized spot in
an aqueous luminol solution, the immobilized enzymes catalyzed the oxidati
on of luminol to emit chemiluminescence, which was detected by a photon cou
nter. The photon-counting intensity was plotted against the position of the
tip to give a two-dimensional image, indicating the activity of immobilize
d enzymes. Since the current was sensitive to the topography of substrate,
the topography image was also obtained by mapping the oxygen reduction curr
ent. (C) 2001 Academic Press.