Wang Baozhen, Tokuda Yu, Tomida Koji, Takahashi Shigehiro, Sato Katsuhiko, Anzai Jun-Ichi
Department of Nutrition and Food Hygiene, School of Public Health, Shandong University, 44 Wenhua Xilu, Jinan, Shandong 250012, China.
Graduate School of Pharmaceutical Sciences, Tohoku University, Aramaki, Aoba-ku, Sendai 980-8578, Japan.
Materials (Basel). 2013 Jun 6;6(6):2351-2359. doi: 10.3390/ma6062351.
The present paper reports the use of an amphoteric copolymer, poly(diallylamine--maleic acid) (PDAMA), as a component of precursor layers (or sacrificial layers) for constructing free-standing layer-by-layer (LbL) films. A PDAMA-poly(styrenesulfonate) (PSS) film or PDAMA-poly(dimethyldiallylammonium chloride) (PDDA) film was coated on the surface of a quartz slide at pH 4.0 or 8.0, respectively, as a sacrificial layer that can be removed by changing the pH. The surface of the sacrificial layer was further covered with LbL films composed of poly(allylamine hydrochloride) (PAH) and PSS. The PAH-PSS films were released from the substrate upon immersing the film-coated quartz slide in acidic or neutral/basic solution, respectively, as a result of the pH-induced dissolution of the PDAMA-PDDA or PDAMA-PSS sacrificial layer. Thus, PDAMA-based sacrificial layers have been demonstrated to dissolve in both acidic and neutral solutions, depending on the type of counter polymer. The thicknesses of the sacrificial layers and released LbL films are crucial factors for constructing free-standing LbL films. The releasing kinetics also depended on the thickness of the crucial layers. The free-standing PAH-PSS films obtained were stable in water or in air in the dry state. PDAMA-based sacrificial layers may be useful in constructing free-standing LbL films containing biomolecules with limited pH stability.
本文报道了两性共聚物聚（二烯丙基胺 - 马来酸）（PDAMA）作为前体层（或牺牲层）的组分用于构建独立的逐层（LbL）膜。分别在pH 4.0或8.0下将PDAMA - 聚（苯乙烯磺酸盐）（PSS）膜或PDAMA - 聚（二甲基二烯丙基氯化铵）（PDDA）膜涂覆在石英载玻片表面，作为可通过改变pH值去除的牺牲层。牺牲层的表面进一步覆盖有由聚（烯丙胺盐酸盐）（PAH）和PSS组成的LbL膜。由于PDAMA - PDDA或PDAMA - PSS牺牲层的pH诱导溶解，将涂有膜的石英载玻片分别浸入酸性或中性/碱性溶液中时，PAH - PSS膜从基底上释放。因此，已证明基于PDAMA的牺牲层可根据抗衡聚合物的类型在酸性和中性溶液中溶解。牺牲层和释放的LbL膜的厚度是构建独立LbL膜的关键因素。释放动力学也取决于关键层的厚度。获得的独立PAH - PSS膜在水或干燥状态的空气中是稳定的。基于PDAMA的牺牲层可能有助于构建含有pH稳定性有限的生物分子的独立LbL膜。
