Ionization of covalent immobilized poly(4-vinylphenol) monolayers measured by ellipsometry, QCM and SPR

Abstract

Covalently immobilized poly(4-vinylphenol) (PVP) monolayer films were fabricated by spin coating PVP on perfluorophenyl azide (PFPA)-functionalized surface followed by UV irradiation. The pH-responsive behavior of these PVP ultrathin films was evaluated by ellipsometry, quartz crystal microbalance (QCM) and surface plasmon resonance (SPR). By monitoring the responses of these films to pH in situ, the ionization constant of the monolayer thin films was obtained. The apparent pKa value of these covalently immobilized PVP monolayers, 13.4 by SPR, was 3 units higher than that of the free polymer in aqueous solution.

Investigating the Effects of Primary Amine Linkers with Different Carbon Chain Lengths on the Acid Dissociation Constant (pKa) for Covalently Immobilized Anthraquinone at the Electrode Surface Using Linear and Non-Linear Fittings

“…The trend of our data is similar to the one that has been reported by Morries et al 53 and Jahanbaksh et al 63 Nevertheless, to monitor the pKa value that corresponds to the carboxylic acid group, titration using NaOH can be carried out in the future since the experiment of AQCA in aqueous buffer solution was the only control experiment for the immobilized AQ. Other technique that can be used to monitor the pKa values for the intermediate species is by using surface plasmon resonance (SPR) as reported by Yan and co-workers 72 which can be an interesting approach to be carried out in the near future.…”

Fabrication of carbohydrate microarrays on a poly(2-hydroxyethyl methacrylate)-based photoactive substrate

“…The polymers were fabricated into an array following the procedure developed in our laboratory. [51][52][53] PFPA was introduced on wafers or glass slides by treating these substrates with a silane-functionalized PFPA (Scheme S-1 †). 54,55 Polymer solutions were then manually printed on the PFPA-functionalized surfaces followed by irradiation to covalently attach the polymer with the aid of PFPA.…”

“…A previously developed procedure was used to evaluate the interactions of proteins with polymers. [51][52][53] The piranhacleaned wafers were soaked in a solution of PFPA-silane in toluene (12.6 mM) under ambient conditions for 4 hours. Polymer arrays were generated by manually spotting solutions of polymers (PS, PHEMA, PEO, PEOX) (10 mg mL −1 ) onto the PFPA-functionalized silicon wafers using a pipette tip followed by irradiation with a medium-pressure Hg lamp (Ace Glass Inc., Vineland, NJ) for 10 min.…”

Electrostatic effect on the dissolution kinetics of poly(4-hydroxystyrene) in alkaline aqueous solution

“…Although it is still unknown whether the pH of 0.26 mol l −1 TMAH solution (pH = approx. 13.3) exceeds the pK a of each acidic group, 2,8) it is at least certain that the repulsive forces exceed the attractive forces due to hydrogen bonds between undissociated acidic groups in 0.26 mol l −1 TMAH solution.…”