title: pH- and sugar-sensitive multilayer films composed of phenylboronic acid (PBA)-modified poly(allylamine hydrochloride) (PBA-PAH) and poly(vinyl alcohol) (PVA): A significant effect of PBA content on the film stability.
abstract: Multilayer thin films composed of phenylboronic acid (PBA)-modified poly(allylamine hydrochloride) (PAH), PBA-PAH, with different PBA contents were prepared to study the effect of PBA content on the stability of the films. An alternate deposition of PBA-PAH and poly(vinyl alcohol) (PVA) on the surface of a quartz slide afforded multilayer films through forming boronate ester bonds between PBA-PAH and PVA. The 10-layered (PBA-PAH/PVA)10 films constructed using PBA-PAHs containing 16% and 26% PBA residues were stable in aqueous solutions over the range of pH 4.0-10.0, whereas the multilayer films composed of PBA-PAHs with 5.9% and 8.3% PBA decomposed at pH 8.0 or lower. The pH-sensitive decomposition of the films was rationalized based on the destabilization of the boronate ester bonds in neutral and acidic solutions. In addition, the (PBA-PAH/PVA)10 films decomposed in glucose and fructose solutions as a result of competitive binding of sugars to PBA-PAH in the films. The sugar response of the films depended on the PBA content in PBA-PAH. The (PBA-PAH/PVA)10 films consisting of 16% and 26% PBA-substituted PBA-PAHs are sensitive to physiological relevant level of glucose at pH7.4 while stable in glucose-free solution, suggesting a potential use of the films in constructing glucose-induced delivery systems.
authors.affiliation: Graduate School of Pharmaceutical Sciences, Tohoku University, Aramaki, Aoba-ku, Sendai 980-8578, Japan.
authors.forename: Masaru
authors.initials: M
authors.lastname: Seno
authors.affiliation: School of Pharmaceutical Science, Ohu University, 31-1 Misumido, Tomita-machi, Koriyama, Fukushima 963-8611, Japan.
authors.forename: Kentaro
authors.initials: K
authors.lastname: Yoshida
authors.affiliation: Graduate School of Pharmaceutical Sciences, Tohoku University, Aramaki, Aoba-ku, Sendai 980-8578, Japan.
authors.forename: Katsuhiko
authors.initials: K
authors.lastname: Sato
authors.affiliation: Graduate School of Pharmaceutical Sciences, Tohoku University, Aramaki, Aoba-ku, Sendai 980-8578, Japan. Electronic address: junanzai@mail.pharm.tohoku.ac.jp.
authors.forename: Jun-ichi
authors.initials: J
authors.lastname: Anzai
mesh_terms: D001897:Boronic Acids / Q000737:chemistry*; D002241:Carbohydrates / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D008567:Membranes, Artificial; D011073:Polyamines / Q000737:chemistry*; D011142:Polyvinyl Alcohol / Q000737:chemistry*
chemical_list: D001897:Boronic Acids; D002241:Carbohydrates; D008567:Membranes, Artificial; D011073:Polyamines; C063994:polyallylamine; D011142:Polyvinyl Alcohol; C010686:benzeneboronic acid
keywords: Fructose; Glucose; Layer-by-layer film; Phenylboronic acid; Sugar-sensitivity; pH-sensitivity