Metallothioneins (MTs) are a group of low-molecular weight (~6 -10kDa), cysteine-rich, evolutionarily conserved proteins, found in generally all life forms. The MTs are multi-functional and play crucial roles in the transport of essential trace elements as well as in the detoxification of harmful metallic elements 1. Four major MT isoforms, MT-1, MT-2, MT-3 and MT-4, have been identified in mammals 2. Specifically, MT-3 has been reported to be secreted mainly in neural cells. Recent reports established that this isoform play an important protective role in brain injury and metal-linked neurodegenerative diseases 3. In general, MT is known to modulate three basic processes: the release of hydroxyl radical or nitric oxide 4, apoptosis 5 and the binding and exchange of heavy metals such as zinc 6, cadmium 7 or copper 8. Previous studies have shown a positive correlation between the expression of MT with invasion, metastasis and poor prognosis in various cancers, including head and neck cancers 9, where increasing levels of MT concentration in tumor (vs. healthy tissues) was observed 10. Moreover; due to high affinity towards heavy metals, MT can be employed for modification of electrodes in development of electrochemical biosensors 11. In view of these facts, immobilization of MT on paramagnetic particles (PMPs) may provide many possibilites, such as simplification of biosensing of low levels of MT, through its pre-concentration. The present study demonstrates immobilization of MT on a surface of paramagnetic particles (gold modified). For confirmation of MT presence two detection techniques were employed: matrix-assisted laser desorption/ionization - time of flight mass spectrometry and differential pulse voltammetry with adsorptive transfer technique utilizing Brdicka solution as supporting electrolyte. For binding capacity evaluation MT isolated from rabbit liver was employed and ideal particles for its immobilization were chosen, simultaneously with optimization of immobilization conditions (pH and temperature).

Central European Institute of Technology Brno University of Technology

Department of Chemistry and Biochemistry Mendel University in Brno

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