title: Functionalized ultra-low fouling carboxy- and hydroxy-functional surface platforms: functionalization capacity, biorecognition capability and resistance to fouling from undiluted biological media.
abstract: The non-specific binding of non-target species to functionalized surfaces of biosensors continues to be challenge for biosensing in real-world media. Three different low-fouling and functionalizable surface platforms were employed to study the effect of functionalization on fouling resistance from several types of undiluted media including blood plasma and food media. The surface platforms investigated in this work included two polymer brushes: hydroxy-functional poly(2-hydroxyethyl methacrylate) (pHEMA) and carboxy-functional poly(carboxybetaine acrylamide) (pCBAA), and a standard OEG-based carboxy-functional alkanethiolate self-assembled monolayer (AT-SAM). The wet and dry polymer brushes were analyzed by AFM, ellipsometry, FT-IRRAS, and surface plasmon resonance (SPR). The surfaces were functionalized by the covalent attachment of antibodies, streptavidin, and oligonucleotides and the binding and biorecognition characteristics of the coatings were compared. We found that functionalization did not substantially affect the ultra-low fouling properties of pCBAA (plasma fouling of ~20 ng/cm(2)), a finding in contrast with pHEMA that completely lost its resistance to fouling after the activation of hydroxyl groups. Blocking a functionalized AT-SAM covalently with BSA decreased fouling down to the level comparable to unblocked pCBAA. However, the biorecognition capability of blocked functionalized AT-SAM was poor in comparison with functionalized pCBAA. Limits of detection of Escherichia coli O157:H7 in undiluted milk were determined to be 6×10(4), 8×10(5), and 6×10(5) cells/ml for pCBAA, pHEMA, and AT-SAM-blocked, respectively. Effect of analyte size on biorecognition activity of functionalized coatings was investigated and it was shown that the best performance in terms of overall fouling resistance and biorecognition capability is provided by pCBAA.
authors: Institute of Photonics and Electronics, Academy of Sciences of the Czech Republic, v.v.i., Chaberská 57, 18251 Prague, Czech Republic.
authors: Hana
authors: H
authors: Vaisocherová
authors: Veronika
authors: V
authors: Ševců
authors: Pavel
authors: P
authors: Adam
authors: Barbora
authors: B
authors: Špačková
authors: Kateřina
authors: K
authors: Hegnerová
authors: Andres
authors: A
authors: de los Santos Pereira
authors: Cesar
authors: C
authors: Rodriguez-Emmenegger
authors: Tomáš
authors: T
authors: Riedel
authors: Milan
authors: M
authors: Houska
authors: Eduard
authors: E
authors: Brynda
authors: Jiří
authors: J
authors: Homola
mesh_terms: D000178:Acrylamides / Q000737:chemistry*; D000327:Adsorption; D000818:Animals; D004926:Escherichia coli / Q000302:isolation & purification*; D057230:Limit of Detection; D008892:Milk / Q000382:microbiology*; D011102:Polyhydroxyethyl Methacrylate / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry*; D013438:Sulfhydryl Compounds / Q000737:chemistry; D020349:Surface Plasmon Resonance / Q000379:methods*; D013499:Surface Properties
chemical_list: D000178:Acrylamides; D011108:Polymers; D013438:Sulfhydryl Compounds; C533866:poly(carboxybetaine acrylamide); D011102:Polyhydroxyethyl Methacrylate
keywords: Functionalization; Low-fouling coatings; Polymer brushes; Surface chemistry; Surface plasmon resonance sensor