Temperature-Modulated Interaction Changes with Adenosine Nucleotides on Intelligent Cationic, Thermoresponsive Surfaces1
Temperature-Modulated Interaction Changes with Adenosine Nucleotides on Intelligent Cationic, Thermoresponsive Surfaces1
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智能阳离子热响应表面上腺苷核苷酸的温度调节相互作用变化1
DOI：
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发表时间：
2007
期刊：
影响因子：
--
通讯作者：
K. Sakai
中科院分区：
文献类型：
--
作者：
A. Kikuchi;J. Kobayashi;T. Okano;T. Iwasa;K. Sakai
将薄层聚（n-异丙基丙烯酰胺-co-正丁基甲基丙烯酸酯-co-n， n-二甲氨基丙基丙烯酰胺）（IBD）共聚物凝胶共价引入到引发剂固定的二氧化硅球表面，以形成热敏智能阳离子表面。表面表现出电荷密度的热响应性变化以及亲疏水特性。在疏水环境下，阳离子氨基弱去质子化导致聚合物链脱水，分子间/分子内聚集，导致表面电荷密度降低。共聚物中二甲胺侧基的热响应性pKa位移以及温度升高时表面电位的变化证实了这一点。利用IBD共聚物固定表面的独特特性，通过热刺激调节高效液相色谱中腺苷核苷酸的保留。在较低温度下，腺苷核苷酸表现出较高的保留率，这主要是由离子与带正电的表面相互作用所致。随着温度的升高，它们的保留时间缩短，在聚合物转变温度以上观察到剧烈的变化。这是溶质相互作用受热响应性表面电荷密度变化和疏水性改变调控的有力证据。此外，我们证实了在不改变流动相组成的情况下，通过步进-温度梯度调节核苷酸保留。这些发现将有利于利用这种刺激响应表面分离水系统中的生物活性化合物和环境影响。
Thin layer poly(N-isopropylacrylamide-co-n-butyl-methacrylate-co-N,N-dimethylaminopropylacrylamide) (IBD) copolymer gels are covalently introduced to initiator immobilized silica bead surfaces to create thermally sensitive intelligent cationic surfaces. The surface shows thermoresponsive changes in charge density as well as hydrophilic/hydrophobic character. The polymer chains dehydrate and inter-/intra-molecular aggregation occurs due to weakly deprotonated cationic amino groups in the hydrophobized circumstances, resulting in the surface charge density decrease. This was corroborated by the thermoresponsive pKa shift of dimethylamino side groups in the copolymers as well as the surface potential changes at elevated temperature. The unique characteristics of the IBD copolymer-immobilized surfaces were applied to regulate adenosine nucleotides retention in high-performance liquid chromatography using aqueous mobile phase by thermal stimulus. At lower temperature, adenosine nucleotides showed higher retention which was primarily driven by ionic interaction with positively charged surfaces. With increasing temperatures, their retention was shortened and a drastic change was observed above the polymer transition temperatures. This is strong evidence that the solute interaction is being regulated by the thermoresponsive surface charge density changes and hydrophobic alterations. Furthermore, we confirmed the modulation of nucleotide retention by step-temperature gradient without changing mobile phase composition. These findings should be beneficial in utilizing this stimuli responsive surface for the separation of bioactive compounds in aqueous system and environmental impact.
通过自动液相色谱从生物液体中等度分离 ATP 及其降解产物。
影响因子：
9.3
作者：
Tekkanat,KK;Fox,IH
通讯作者：
Fox,IH