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A. V. Brusnichkin, D. A. Nedosekin, E. S. Ryndina, M. A. Proskurnin, E. Yu. Gleb, D. O. Lapotko, Yu. A. Vladimirov, V. P. Zharov
Determination of various haemoglobin
species with thermal-lens spectrometry
Abstract
Thermal-lens determination of desoxyhaemoglobin,
oxyhaemoglobin, carboxyhaemoglobin, methaemoglobin, cyanohaemoglobin, and
hemichrome with thermal-lens spectrometry; the limits of detection are at the
level of 10–8 M (2–5 mg/mL depending on haemoglobin species). The
behavior of thermal lens formation and the limits of detection are in agreement
with the theoretical modeling implementing previously developed approach for
describing the process of generation of the thermal-lens signal in complex
(inhomogeneous) systems. For all the studied haemoglobin species, the
thermooptical response linearly depends on the excitation laser power in the
range 1–50 mW (532, 514.5 and 488 nm). Under the conditions of thermal-lens
experiment, the total increase in the temperature due to the heating of the
solution after the absorption of laser radiation by haemoglobin, which was
equal to 0.0001 K. The error of determination of desoxyhaemoglobin with
thermal-lens spectrometry (for the maximum excitation laser power of 210 mW at
532 nm) due to the interference from oxyhaemoglobin is not above 3% for the
ratio of the species of 10 : 1. In the opposite case (the
determination of oxyhaemoglobin against desoxyhaemoglobin) the error for the
same ratio of test and interfering species is not above 5%.
Copyright (C) Chemistry Dept., Moscow State University, 2002
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