Hemoglobin (Hb) has been one of the most extensively studied proteins.
It is well known for being a carrier of oxygen. It also aids, both directly
and indirectly, the transport of carbon dioxide and regulates the
pH of blood [7]. Hb is the major hemoprotein of the red blood cell,
which can reversibly bind with many kinds of endogenous and exogenous
agents [8]. The emission of tryptophan is highly sensitive to its
local environment, and is thus often used as a reporter group for protein
conformational changes [9]. Fluorescence quenching is an important
method to study the interaction of substances with protein because it
is sensitive and relatively easy to use [10–12]. In literature, most studied
proteins for drug binding are bovine serum albumin and human serum
albumin. However, there are several studies on interactions between
hemoglobin and drugs that have been reported by fluorescence and
thermogravimetry techniques [12,13]. Identification of interactions between
drugs and hemoglobin is very crucial since these interactions
may have undesirable effects on their main function. Studies on interactions
between albumin and drugs have been widely reported. But, the
reports on hemoglobin are very limited. Identification of the interactions
may help us understand and prevent the side effect of the drugs
in human metabolism. This study reveals that the material has still a
good potential for the planning of new applications. Hemoglobin
which is an abundant protein in serum plasma was used for the preparation
of a protein–iron oxide nanoparticle system as a drug carrier.
Superparamagnetic iron oxide nanoparticle–protein biocompatible agglomerates
served as a nanocarrier for the hydrophobic anticancer
drug thiabendazole. In considering the role of this protein in drug metabolism,
the determination of the amount of drug that interactedwith this serum protein can provide information about the structural
characteristic and the therapeutic effectiveness of the drug. The analysis
of thermal decomposition is an important tool for estimating
thermal stability and calculating the kinetic parameters of nanoparticle–
biomolecule systems. In this study, the interaction of Tbz with Hb was
evaluated by using these techniques. The characterization of the
protein–nanoparticle system was also examined by an FT-IR spectrometer
and a scanning electron microscope (SEM).