Binding of l-tryptophan and bovine serum albumin by novel gold nanoparticles capped with amphiphilic sulfonatomethylated calixresorcinarenes

摘要: Abstract A simple, one-step synthesis of spherical gold nanoparticles (dcore = 38 and 25 nm) in aqueous solution has been carried out using sulfonatomethylated calixresorcinarenes with methyl (C1S) pentyl (C5S) substituents on the lower rim both as reducing stabilizing agents. The obtained, Au@C1S Au@C5S, were characterized by absorption spectrophotometry, TEM, DLS, IR TGA. are stabilized interaction that occurs between macrocycles' sulfo-groups metal surface. It shown, Au@C5S have a higher thermal stability than due to denser packing macrocycle surface caused amphiphilic nature C5S macrocycle. or associate cooperatively l -tryptophan form nanoscale system capable spectral response changing pH solution. detailed study С5S BSA was DLS fluorimetry. found stable complexes protein, which confirmed static character quenching fluorescence. mechanism macrocycles investigated. (KSV) binding (Kas) constants, number sites (n), thermodynamic parameters (ΔG, ΔH, ΔS) calculated. process protein free modified is exothermic spontaneous, hydrogen bonding van der Waals interactions make major contribution into binding. synchronous fluorescence method showed influences microenvironment tryptophan residues molecule. leads changes structure well physicochemical characteristics nanoparticles, promising aspect use such systems for transport molecules their visualization-detection biological media.