We have studied the interaction between polycyclic aromatic hydrocarbons (pyrene and anthracene) with human serum albumin
(HSA) and human blood plasma. We have shown that the increase in the fluorescence intensity and the decrease in the polarity
index of pyrene on going from an aqueous solution to a pH 7.4 buffer solution of HSA suggests that polycyclic aromatic hydrocarbons
are localized in the hydrophobic microphase of the proteins. The increase in the fluorescence intensity for anthracene and
pyrene, and also the decrease in the polarity index of pyrene on going from HSA to blood plasma is connected with the fact
that polycyclic aromatic hydrocarbons can bind both to plasma proteins and to plasma lipids. When sodium dodecyl sulfate (SDS)
is added to the blood plasma in a concentration greater than the critical micelle concentration, we observe an increase in
the fluorescence intensity and the polarity index of pyrene. We hypothesize that this is connected with localization of pyrene
near the interface between the hydrophobic and hydrophilic phases of the protein-SDS system. We have established that SDS
leads to a change in the structure of blood plasma proteins and promotes escape of polycyclic aromatic hydrocarbons from the
protein globules.
Key words human blood plasma - human serum albumin - polycyclic aromatic hydrocarbons - sodium dodecyl sulfate - fluorescence
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Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 75, No. 3, pp. 379–382, May–June, 2008.