Department of Molecular Chemistry and Biochemistry, Faculty of Science and Engineering, Doshisha University, Kyotanabe, Kyoto, 610-0321, Japan.
Macromol Rapid Commun. 2020 Feb;41(4):e1900550. doi: 10.1002/marc.201900550. Epub 2020 Jan 1.
Thermo-responsive block copolymers are of great interest in biomedical and nanotechnological fields. These polymers achieve a versatile and complex responsiveness through a sophisticated and intricate combination of different thermo-responsive blocks. While their utility is clear, the fundamental design principles of such vinyl polymers are not yet thoroughly understood. Herein, a precise synthesis of sequence-controlled amino-acid-derived vinyl polymers and their unique thermal response in water are reported. Seven distinct block (random) copolymers that contain two kinds of amino acid blocks (poly(N-acryloyl alanine(A)- or glycine(G)-methyl ester)) with the same total chain length (degree of polymerization [DP] ≈30) and chemical composition (A/G ≈1), but with systematic variations in the block sequence and length, with an accuracy target of DP ± 1, are prepared. By specifying the primary structure, the thermal responses including transition temperature, thermo-sensitivity, and microenvironment in the dehydrated state can be finely tuned. These findings offer new directions in the design of structurally and functionally diverse thermo-responsive vinyl polymers.
温敏嵌段共聚物在生物医学和纳米技术领域具有重要的应用价值。这些聚合物通过复杂的组合方式实现了多功能、复杂的响应特性，包含不同的温敏嵌段。虽然它们的用途很明确，但这些乙烯基聚合物的基本设计原则还没有被完全理解。在此，我们报告了一种序列可控的氨基酸衍生的乙烯基聚合物的精确合成及其在水中的独特热响应。我们制备了七种具有不同序列和长度的嵌段（无规）共聚物，这些共聚物包含两种氨基酸嵌段（聚（N-丙烯酰基丙氨酸（A）-或甘氨酸（G）-甲酯）），具有相同的总链长（聚合度 [DP] ≈30）和化学组成（A/G ≈1），但嵌段序列和长度有系统的变化，目标 DP 精度为 ±1。通过指定其一级结构，可以精细地调节包括转变温度、热敏感性和脱水状态下的微环境在内的热响应。这些发现为设计结构和功能多样化的温敏乙烯基聚合物提供了新的方向。
