840
Journal of Luminescence 4O&4l (1988) 840—841 North-Holland, Amsterdam
THE CHEMILUMINESCENCE FROM THE REACTION OF HEMOPROTEINS WITH INORGANIC PEROXIDES
Yaning LIU, member of the Chinese Society of Biophysics; Basic Lab, The Xidiaoyutai Hospital,
No.30, West Diaoyutai,
Xinhua Zl-IAO. Beijing, Chits.
Chemiluminescence from hemoproteins oxidation are composed of two components: the dimol emission of the singlet oxygen and the excited carbonyls, accompanied by the destruction of por~yrin rings.
The biological importance of hemoproteins is NV
cytochrome C
not inferior to DNA. The development of rapid and simple measurement for hemoproteins is certainly of great clinical and biological value.
0.2 0. ~
talase
erritin
It has been reported that in the chemilumi— 0.1 nescent reactions of luminol and lipid peroxides, 1’2. Rut the hemoprotelns act as catalysts instability of luminol has also been noticed3.
50
100
150 t(sec.)
200
250
Furthermore, the pure organic peroxides are hard to come by.
FIGURE 2
We found that when hemin and hemorpoteins
Chemiluminescent emission dynamic Curves cC cy— tochrome C, catalase, ferritin and water blank.
react with inorganic peroxides (sodium perborate or H 202)
in alkaline solution, low—level chemi—
luminescences could be detected )Fig.1,2).
Measured with our home—made luminometer, the luminosity sequence of hemoproteins and control
MV
materials was as follows (the integral time was 6 myoglobin
set to 100 seconds):
hemoglobin
myoglobin > hemoglobin > horseradish per— oxidase > cytochrome C > hemln > catalase > ferrltin > water blank 3 FeSO4 > FeCl3 >
24
hematoporphyrin 2
~
+
iron ion
by OMA—2two multichannel spectroscopy and Determined cutting filters, bands appa~red in the emission spectra: a red band with a peak around 630 nm and a blue band with a peak around 4240 cm
hemin
)Fig.3). 50
100 t(sec.)
150
The red band must be the dm01
emission of
singlet oxygen, as these chemiluminescences could be strongly quenched by a_-carotene. The FIGURE 1 Chemiluminescent emission dynamic curves of myo— glcbin, hemoglobin, horseradish peroxidase and hemin. 0022—23l3/88/$03.50 © Elsevier Science Publishers By. (North-Holland Physics Publishing Division)
blue band is supposed to be the luminescence from the excited carbonyls,
which might be .1 produced through the Dioxetane mechanism
Y. Liu, X. Zhao
/
841
Chemiluminescence from the reaction of hemoproteins
The ground state On the 3d orbits
of iron
ion is paramagnetic.
there are spin—unpaired
elec-
trons, their spin—spin coupling is very weak. After the iron ions being complexed into por—
mt.
both phyrmns, iron their and porphyrin unpaired are electrons markedly are enhanced. involved in the bigger rings conjugations and become highly delocalized, thus the reactivities of
400
500
600
700
Therefore, hems and hematoporphyrin behaved quite differently during oxidation.
stave length (nm)
Good linear relationships between concentration and luminosity were obtained, both for
FIGURE 3 OMA—2 emission spectrum of myoglobin oxidation.
myoglobin at ng level and for horseradish per—
The scavengers of hydroxyl radicals could
oxidase at pg level (the correlation coeffient was 0.9926 and 0.9975, respectively(. These
partially inhibit these chemiluminescences,
chemiluminescences may be helpful to the search
indicating the participation of active oxygen
for new luminescent assays. For example, serum
other than the singlet oxygen.
myoglobmn determination is valuable to the rapid 5 and, diagnosis of acute myocardial infarction if the luminometer is sensitive enough, the
The blank luminescence of sodium perborate in alkaline solution could also be quenched by fl—carotene to great extent and inhibited by
luminescent assay for horseradish peroxidase
hydroxyl radical scavengers to some extent, so
may be a safe substitute for the traditional
the singlet oxygen might partially come from
ELISA, protecting the operator from contacting
the Arneson mechanism
4
the highly carcinogenic substrate, i.e., the
During oxidation the Soret bands of hemin
3,3’—diamincbenzidine(DAR).
and hemoproteins decreased gradually, representing the destruction of porphyrin rings.
ACKNOWLEDGEMENT
The excited carbonyls might come from porphy—
We would like to thank Prof. Lin Me Chun and
rins and their adjacent groups. The luminosity
Cheng Bo Ji for their comments on ferriporphy—
differences among various hemoproteins might
rin and excited carbonyls, as well as Dr. Liu
account for the different amounts of excited
Jing Qing for her help in OMA—2 measurement.
carbonyls produced during oxidation. The fact that different hemoproteins emitted light at different rates when they were cxi—
REFERENCES !.
dized, might be caused by the different expo—
E. Cadenas et ml., Low level chemilumines— cence of biological systems, in: Free Radicals in Riology, ed. W.A. Fryer (Academic Press, Vol.VI, 1984) pp.231—242.
sure states of heme groups to solvents. The chemiluminescence induced by the mixture of hematoporphyrin and iron ion (ferrous or ferric( was much weaker than those of hemin
2. T. Olsson et al., Clin. Chim. Acta, pp.31—40.
138(1984)
3. W.R. Seitz et al., Anal. Chem. 48(1976(1003. and hemoproteins, and there was no apparent porphyrin destruction during oxidation. The complex compound of ferriporphyrin
i.
R.M. Arneson, Arch. (1976(352.
Biochem. Biophys. 136
must play
a unique role in these chemiluminescences.
5. J.P. Chapelle, Eur. Heart J. 3(1982)122.