title: Fabrication of reversible poly(dimethylsiloxane) surfaces via host-guest chemistry and their repeated utilization in cardiac biomarker analysis.
abstract: On the basis of the host-guest interactions between azobenzenes and cyclodextrins, a new strategy for the preparation of a dually functionalized poly(dimethylsiloxane) (PDMS) surface was investigated using surface-initiated atom-transfer radical polymerization (SI-ATRP) and click chemistry. The PDMS substrates were first oxidized in a H(2)SO(4)/H(2)O(2) solution to transform the surface Si-CH(3) groups into Si-OH groups. Then, the SI-ATRP initiator 3-(2-bromoisobutyramido)propyl(trime-thoxy)silane was grafted onto the substrates through a silanization reaction. Sequentially, the poly(ethylene glycol) (PEG) units were introduced onto the PDMS-Br surfaces via SI-ATRP reaction using oligo(ethylene glycol) methacrylate. Afterward, the bromide groups on the surface were converted to azido groups via nucleophilic substitution reaction with NaN(3). Finally, the azido-grafted PDMS surfaces were subjected to a click reaction with alkynyl and PEG-modified β-cyclodextrins, resulting in the grafting of cyclodextrins onto the PDMS surfaces. The composition and chemical state of the modified surfaces were characterized via X-ray photoelectron spectroscopy, and the stability and dynamic characteristics of the cyclodextrin-modified PDMS substrates were investigated via attenuated total reflection-Fourier transform infrared spectroscopy and temporal contact angle experiments. The surface morphology of the modified PDMS surfaces was characterized through imaging using a multimode atomic force microscope. A protein adsorption assay using Alexa Fluor594-labeled bovine serum albumin, Alexa Fluor594-labeled chicken egg albumin, and FITC-labeled lysozyme shows that the prepared PDMS surfaces possess good protein-repelling properties. On-surface studies on the interactions between azobenzenes and the cyclodextrin-modified surfaces reveal that the reversible binding of azobenzene to the cyclodextrin-modified PDMS surfaces and its subsequent release can be reversibly controlled using UV irradiation. Sandwich fluoroimmunoassay of the cardiac markers myoglobin and fatty acid-binding protein demonstrates that the cyclodextrin-modified PDMS surfaces can be repeatedly utilized in disease biomarker analysis.
authors: Colleges of Science and Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, P R China.
authors: Yanrong
authors: Y
authors: Zhang
authors: Li
authors: L
authors: Ren
authors: Qin
authors: Q
authors: Tu
authors: Xueqin
authors: X
authors: Wang
authors: Rui
authors: R
authors: Liu
authors: Li
authors: L
authors: Li
authors: Jian-Chun
authors: JC
authors: Wang
authors: Wenming
authors: W
authors: Liu
authors: Juan
authors: J
authors: Xu
authors: Jinyi
authors: J
authors: Wang
mesh_terms: D000818:Animals; D001391:Azo Compounds / Q000737:chemistry; D015415:Biomarkers / Q000032:analysis*; D002318:Cardiovascular Diseases / Q000378:metabolism; D002417:Cattle; D004129:Dimethylpolysiloxanes / Q000737:chemistry*; D050556:Fatty Acid-Binding Proteins / Q000032:analysis; D015200:Fluoroimmunoassay; D006801:Humans; D009113:Muramidase / Q000737:chemistry; D009211:Myoglobin / Q000032:analysis; D009930:Organic Chemicals / Q000737:chemistry; D056951:Photoelectron Spectroscopy; D011092:Polyethylene Glycols / Q000737:chemistry; D012710:Serum Albumin, Bovine / Q000737:chemistry; D013499:Surface Properties; D047392:beta-Cyclodextrins / Q000737:chemistry
chemical_list: C417664:Alexa594; D001391:Azo Compounds; D015415:Biomarkers; D004129:Dimethylpolysiloxanes; D050556:Fatty Acid-Binding Proteins; D009211:Myoglobin; D009930:Organic Chemicals; D047392:beta-Cyclodextrins; D012710:Serum Albumin, Bovine; D011092:Polyethylene Glycols; C013830:baysilon; D009113:Muramidase; C009850:azobenzene