| Recently, azobenzene derivatives have been intensively studied due to their trans-cis isomerization properties and the accompanied change of their physical properties. Therefore, they have been widely used in many fields, such as optical information storage materials, nonlinear optical materials, liquid crystal materials, light adjust and controlling materials of biological activity and nanophase materials. In the present work, three kinds of azobenzene-containing monomers were synthesized and polymerized to be applied as the sensitive layers for biomolecules binding. The chemical structures of them were characterized by Fourier Transform Infrared Spectroscopy (FT-IR) and Nucler Mgnetic Reonnce Spectroeter (1H NMR).Firstly, BSA adsorption on poly (4-((4-chlorophenyl) diazenyl) phenyl methacrylate), which was prepared by the method of free radical polymerization, was investigated by surface plasmon resonance of spectroscopy (SPR) in details. At the very beginning, the polymer was dissolved in the solvent. The polymer solution was dropped onto the substrates, i.e., Si or Au, and formed the polymer film. FT-IR was used to characterize the chemical structure of monomers and polymer. And the reversible photoisomerization of polymer film was studied by contact angle (CA) and UV-Vis absorption spectrum. Moreover, the reversible processes of photoisomerization of azopolymer can be induced by UV light. It suggests that the rate of photoisomerization is fast and first-order constant. Afterwards, before and after the irradiation of UV light, the adsorption kinetics of BSA on azopolymer surface was measured by SPR. The results showed that BSA molecules can be adsorbed onto the polymer film reversibly.In order to understand the effect of the polymer structure on biomolecules anchor and improve the controllable ability of biomoleucles onto the azopolymer surfaces, the grafting polymer brushes which is regular structure and narrow distribution of molecular weight was prepared on Au and silicon substrates by the method of surface-initiated atom transfer radical polymerization (ATRP). Herein, 6-mercaptohexyl 2-bromo-2-methylpropanoate and 6-(3-dimethoxy (methyl) silyl)-2-bromide-2-methyl propanamide were used as initiators and self-assembled onto Au and silicon substrates, respectively. Also, the chemical structure and photo-properties of azopolymer were characterized by FT-IR and UV. Moreover, the variations of the morphology of the surface before and after UV irradiation were measured by Atomic Force Microscopy (AFM). While as the adsorption kinetics of BSA on azopolymer surface was measured in situ by SPR. Comparing with the first azopolymer, the similar result was obtained. BSA could be adsorbed onto the polymer surface reversibly. Furthermore, BSA adsorption was also depended on the type of functional groups contained in the azopolymer chains.Aim to enhance the controllability on biomolecules anchor on polymer matrix, pyrrole group was introduced into the azobenzene molecules. Polymer (poly 4-((4-((6-(1H-pyrrol-1-yl) hexyl) oxy) phenyl) diazenyl) benzoic acid, PPyAzoCOOH) was prepared by chemical method. Therefore, the polymer synthesized will be conductive and photo-isomerized. Herein, the homopolymer was prepared and spin-coated onto the Au surfaces. Afterwards, the chemical, photo and surface properties were measured by FT-IR, UV, AFM and CA. Comparing with the former two polymers, the rate of photoisomerization of azopolymer is much slower. Cyclic voltammogram was applied to detect the electrochemical properties of azopolymer before and after BSA binding.The photo-isomerization of three azopolymers is different and depended on the spacer lengenth between azobenzene group and the backbone of polymers. The rate of isomerization of azopolymers becomes slow with the spacer lengenth increasing. Furthermore, the BSA adsorption is affected mainly by the types of the functional groups of azopolymers and the conditions of the external fields.
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