Biomedical Engineering Reference
In-Depth Information
1
2
3
MKM
0,4
0,4
0,4
2,0
0,3
0,5
0,3
0,5
0,3
1,5
0,2
1,0
0,2
1,0
0,2
1,0
0,1
1,5
0,1
0,5
1,5
0,1
Figure 13.5
Porous silicon at the atom force microscopy. 1 - bare surface, 2 - with specii c
antibodies, 3 - with Ab-Ag complex.
samples with Ab immobilized from the solution of 4 μg/ml decreased only
for 40%, while in the case of Ab concentrations 100 and 500 μg/ml the
changes in the PhL intensity achieved their maximum level. At the same
time, the concentrations equal to 100 and 500 μg/ml were rather similar,
which allowed considering that the concentration of Ab equal to 100 μg/
ml was sui cient for ei cient registration of Mb. It was shown that the PhL
intensity did not change at the immersion of the PS sample with deposited
Ab (concentration of Ab: 100 μg/ml; time of immobilisation: 60 min) into
the Mb solution of the concentration equal to 1.0 ng/ml during 15 min.
h e magnitude of concentrations detected lied in the range from 0.01 to
10 μg of Mb in 1ml of solution.
PhL intensity of PS samples retained in undiluted serum was about 50%,
while PhL intensity of PS samples immersed into diluted serum samples
approached to 100%. At the same time a dif erence between data obtained
for undiluted serum and Mb solution 100 ng/ml was observed. In case of
Mb solution the PhL intensity decreased for 40% while for undiluted serum
this value was 50%. Such a dif erence in the magnitude of the decrease in
the PhL intensity can testify about probable inl uence of other PS samples
with Ab on the surfaces (concentration of Ab: 100 μg/ml; time of immobi-
lization: 60 min) were immersed into those three samples of serum for 15
min and then the PhL intensity was measured. h e results showed that the
PhL intensity of PS samples retained in undiluted serum was about 50%,
while PhL intensity of PS samples immersed into diluted serum samples
approached to 100%. Such changes of the PhL intensity in case of undi-
luted serum can be explained either by the fact that serum of healthy peo-
ple can contain Mb in concentrations up to 100 ng/ml or by the inl uence
of others proteins. h e last is less probable, since according to our previous
results it was shown that sorption of albumin or IgG on the PS surface did
not af ect the PhL intensity. At the same time, a dif erence between data
