Resistance to enzymatic cleavage of peptide agents immobilised on magnetic nanoparticles Fe 3 O 4

Abstract

A broad and significant group of drugs include peptide compounds. The peptides are also crucial in the delivery of amino acid analogues, which are important inhibitors of pathogenic cell enzymes. Unfortunately, peptide agents have a number of disadvantages which limit their use. Among the most significant is their low stability in blood serum, caused by peptidase cleavage. This problem has not been solved conclusively so far. We proposed immobilisation of peptides on ‘magnetic nanoparticles (MNPs) Fe3O4’ as a potentially effective way to protect peptide agents from enzymatic cleavage. A simple method of linking dipeptides with N-terminal lysine to the nanoparticles surface via a linker containing boronic acid was designed. This method of bonding enables the measurement of the degree of enzymatic hydrolysis under in vitro conditions of the peptides immobilised on the nanoparticles using a UV–Vis spectrophotometric technique. The characterisation of morphology of the obtained nanostructures was also carried out. It has been demonstrated that peptides immobilised on MNPs Fe3O4 are more resistant to enzymatic hydrolysis than peptides in their unattached form. The MNPs Fe3O4 seem to be very useful as peptide-drug carriers.