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Updated: Jul 13, 2026

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Microbubble Fabrication of Concave-porosity PDMS Beads
Published on: December 15, 2015
在水溶液中乙烯酸盐的形成和稳定性
Ana Rios1, John P Richard, Tina L Amyes
1Department of Chemistry, University at Buffalo, SUNY, Buffalo, New York 14260-3000, USA.
Journal of the American Chemical Society
|July 11, 2002
概括
这项研究量化了N-终端的脱质率,揭示它们的反应性明显高于内部残留物. 这种差异对于理解和蛋白质化学是至关重要的.
科学领域:
- 生物物理化学 生物物理化学
- 化学动力学 化学动力学
- 有机化学 有机化学
背景情况:
- 和蛋白质的稳定性受到其终端组的反应性的影响.
- 了解α-氨基碳的脱质动力学对于预测化学行为至关重要.
研究的目的:
- 确定各种碳酸在D2O中脱质的二次速率常数.
- 为了估计H2O中的氧化离子的质子转移速率.
- 调查影响酸中α-氨基和α-碳基碳的酸度的因素.
主要方法:
- 使用二氧化离子 (D2O) 来确定速率常数的动力测量.
- 在H2O中估计氧化离子速率常数.
- 在log k(HO) 和碳酸pKa.之间进行线性相关性分析.
主要成果:
- 确定了N端和内部α-氨基碳以及N-乙化中的乙甲基和α-氨基碳的脱化第二阶速常数 (k(DO)).
- 这些碳酸的pKa值估计在23.9~30.8.之间.
- 在一个质子化N端的α-氨基碳是大约130倍更有反应性比在内部残留.
结论:
- N-终端α-氨基基组的增强反应性归因于马库斯较低的内在屏障,用于解质化 cationic alpha-carbonyl 碳酸.
- 尽管电子吸收强度有差异,但阴离子NH3+和中性NHAc组都类似地降低了α-碳基碳酸的pKa.
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