Zhang Pu, Henthorn David B
Department of Chemical and Biological Engineering, Missouri University of Science and Technology, 143 Schrenk Hall, Rolla, Missouri 65409, USA.
J Nanosci Nanotechnol. 2009 Aug;9(8):4747-52. doi: 10.1166/jnn.2009.1274.
In this work, various methods to functionalize single wall carbon nanotubes with immobilized enzyme for bioanalytical application were investigated. Several different conjugation methods, including both covalent and noncovalent methodologies, were compared and the resulting enzyme loading and retained activity were evaluated. After enzymatic modification, the addition of amphiphilic molecules to aid in nanotube dispersability was also studies and its effect on enzyme activity determined. Different characterization tools were employed to observe the morphological changes before and after the functionalization, including FTIR, TEM, and AFM. Both the enzyme loading amount and percent retained activity was greatest for modification when the linker molecule 1-pyrenebutanoic acid succinimidyl ester was used to form the enzyme-carbon nanotube conjugate. In addition, several possible mechanisms were proposed to explain the loss of enzymatic activity following immobilization. While the addition of amphiphilic surfactant molecules aided in the ultimate dispersability of the carbon nanotubes in aqueous media, enzymatic activity was further decreased.
在这项工作中，研究了多种用固定化酶功能化单壁碳纳米管以用于生物分析应用的方法。比较了几种不同的偶联方法，包括共价和非共价方法，并评估了所得的酶负载量和保留活性。酶促修饰后，还研究了添加两亲分子以帮助纳米管分散，并确定了其对酶活性的影响。采用了不同的表征工具来观察功能化前后的形态变化，包括傅里叶变换红外光谱（FTIR）、透射电子显微镜（TEM）和原子力显微镜（AFM）。当使用连接分子1-芘丁酸琥珀酰亚胺酯形成酶-碳纳米管缀合物时，修饰后的酶负载量和保留活性百分比均最高。此外，还提出了几种可能的机制来解释固定化后酶活性的丧失。虽然添加两亲性表面活性剂分子有助于碳纳米管在水性介质中的最终分散，但酶活性进一步降低。
