Ligand fishing using new chitosan based functionalized Androgen Receptor magnetic particles

Abstract

Superparamagnetic nanoparticles with chemically modified chitosan has been proposed as a potential support for the immobilization of the androgen receptor (AR). The study involved comparison of different AR carriers like commercially available magnetic beads coated with silica (BcMag) and chitosan coated nanoparticles with different amount of amino groups. The immobilization was carried out through covalent immobilization of the AR through the terminal amino group or through available carboxylic acids. The initial characterization of the AR coated magnetic beads was carried out with dihydrotestosterone, a known AR ligand. Subsequently, chitosan modified nanporticles with long-distanced primary amino groups (Fe3O4CS-(NH2)3) (upto 8.34 mM/g) were used for further study to isolate known AR ligands (bicalutamide, flutamide, hydroxyflutamide and levonogestrel) from a mixture of tested compounds in ammonium acetate buffer [10 mM, pH 7.4]. The results showed that the selected nanoparticles are a promising semi-quantitative tool for the identification of high affinity compounds to AR and might be of special importance in the identification of novel agonists or antiandrogens.

Chitosan–Collagen Coated Magnetic Nanoparticles for Lipase Immobilization—New Type of “Enzyme Friendly” Polymer Shell Crosslinking with Squaric Acid

“…Magnetic nanoparticles (MNPs) are widely used as supports for physical and chemical biomolecule immobilization [15][16][17], with usually a high load of ligands [18][19][20][21]. However, pure magnetite has a poor colloidal stability, particularly in neutral pH, so it needs stabilization and surface modification [22].…”

Polymer-Coated Magnetite Nanoparticles for Protein Immobilization

“…Later, Ziegler-Borowska and co-authors prepared magnetite nanoparticles coated with chemically-modified chitosan rich in free amino groups remote from the polymer chain ( Figure 19 ) [ 183 , 185 , 198 , 199 , 200 , 201 , 202 ]. First, chitosan-coated magnetite nanoparticles were synthesized by an in situ co-precipitation reaction in an alkaline solution.…”

“…Then, the reactive chitosan groups, hydroxyl and amino, were used for its functionalization, obtaining three polymer coatings with different content of amino groups able to bind protein ( Figure 19 ). Prepared nanoparticles were used for the chemical immobilization of proteins: lipase from Candida rugosa [ 183 , 193 , 201 ], human serum albumin (HSA) [ 185 , 199 ], and the androgen receptor (AR) [ 202 ].…”

Testing for Ketoprofen Binding to HSA Coated Magnetic Nanoparticles under Normal Conditions and after Oxidative Stress

“…It is known from our previous studies that the surface of magnetic nanoparticles can be designed and modified at different ways for various application [11][12][13]. In addition, it is proved by an anti-HSA test that HSA immobilized on the surface of MNPs retains its activity [14,15].…”