Ligand fishing using new chitosan based functionalized AndrogenReceptor magnetic particles

Abstract

Superparamagnetic nanoparticles with chemically modified chitosan has been proposed as a potentialsupport for the immobilization of the androgen receptor (AR). The study involved comparison of differentAR carriers like commercially available magnetic beads coated with silica (BcMag) and chitosan coatednanoparticles with different amount of amino groups. The immobilization was carried out through cova-lent 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 aminogroups (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 inammonium acetate buffer [10 mM, pH 7.4]. The results showed that the selected nanoparticles are apromising semi-quantitative tool for the identification of high affinity compounds to AR and might be ofspecial importance in the identification of novel agonists or antiandrogens.